LP2951-03YN [MICROCHIP]
LDO Voltage Regulators Low Drop Out Regulator (Lead Free);型号: | LP2951-03YN |
厂家: | MICROCHIP |
描述: | LDO Voltage Regulators Low Drop Out Regulator (Lead Free) 光电二极管 输出元件 调节器 |
文件: | 总30页 (文件大小:2627K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
LP2951
100 mA Low-Dropout Voltage Regulator
Features
General Description
• High Accuracy 5V, Guaranteed 100 mA Output
• Extremely Low Quiescent Current
• Low-Dropout Voltage
The LP2951 is micropower voltage regulators with very
low dropout voltage (typically 40 mV at light loads and
380 mV at 100 mA), and very low quiescent current
(75 μA typical). The quiescent current of the LP2951
increases only slightly in dropout, thus prolonging
battery life. This feature, among others, makes the
LP2951 ideally suited for use in battery-powered
systems.
• Extremely Tight Load and Line Regulation
• Very Low Temperature Coefficient
• Use as Regulator or Reference
• Needs Only 1 μF for Stability
• Current and Thermal Limiting
Available system functions, such as programmable
output voltage and logic-controlled shutdown, are
available as well.
• Error Flag Warns of Output Dropout
• Logic-Controlled Electronic Shutdown
• Output Programmable from 1.24V to 29V
Additional features available with the LP2951 also
include an error flag output that warns of a low output
voltage, which is often due to failing batteries on the
input. This may also be used as a power-on reset. A
logic-compatible shutdown input is also available which
enables the regulator to be switched on and off. This
part may also be pin-strapped for a 5V output, or
programmed from 1.24V to 29V with the use of two
external resistors.
Applications
• Automotive Electronics
• Voltage Reference
• Avionics
The LP2951 is available as either a -02 or -03 version.
The -02 and -03 versions are guaranteed for junction
temperatures from -40°C to +125°C; the -02 version
has a tighter output and reference voltage specification
range over temperature.
The LP2951 have a tight initial tolerance (0.5% typical),
a very low output voltage temperature coefficient which
allows use as a low-power voltage reference, and
extremely good load and line regulation (0.05%
typical). This greatly reduces the error in the overall
circuit, and is the result of careful design techniques
and process control.
Package Types
LP2951
DIP & SOIC
Top View
1
8
INPUT
OUTPUT
SENSE
2
3
4
7
6
5
FEEDBACK
SHUTDOWN
GROUND
5V TAP
ERROR
* See MIC2950 for a part with: 1) higher output
(150 mA), 2) transient protection (60V), and 3) reverse
input protection to –20V.
2017 Microchip Technology Inc.
DS20005736A-page 1
LP2951
Functional Block Diagram
UNREGULATED DC
5V
150 mA
MAX.
7
8
1
+
FEEDBACK
INPUT
OUTPUT
2
SENSE
6
+
–
182
kΩ
3
ERROR
330
kΩ
FROM
CMOS
OR TTL
5V TAP
5
AMPLIFIER
SHUT-
DOWN
+
1.5 μF
60 mV
+
60
+
–
kΩ
TO CMOS
ERROR
4
ERROR
OR TTL
+
DETECTION
1.23 V
COMPARATOR
REF.
GROUND
Typical Application Diagrams
+V
+V
IN
+VIN
C-MOS
GATE
*SLEEP
8
+VIN
INPUT
470 kΩ
47kΩ
ERROR
5
OUTPUT
*VOUT ≈ VIN
1
8
VOUT
ERROR
LP2951
IN
+V
OUT
1
ERROR
OUTPUT
5
V
OUT
ERROR
LP2951
SHUTDOWN 3
INPUT
200kΩ
SO
1%
3
+
2N3906
100pF
SHUTDOWN
INPUT
SD
3.3μF
100kΩ
GND
FB
OFF
FB
GND
ON
7
4
7
4
1%
100kΩ
*MINIMUM INPUT-OUTPUT VOLTAGE RANGES FROM 40 mV TO 400 mV,
DEPENDING ON LOAD CURRENT. CURRENT LIMIT IS TYPICALLY 160 mA.
*HIGH INPUT LOWERS VOUT TO 2.5V
5V REGULATOR WITH 2.5V
SLEEP FUNCTION
WIDE INPUT VOLTAGE RANGE
CURRENT LIMITER
+V = 2 30V
1.23
I
L
LOAD
I =
L
R
8
V
IN
1
V
OUT
LP2951
SHUTDOWN
INPUT
3
0.1μF
SD
GND
FB
4
7
R
1%
1μF
LOW DRIFT CURRENT SOURCE
DS20005736A-page 2
2017 Microchip Technology Inc.
LP2951
Typical Application Diagrams
+V
D
IN
1
+V
IN
8
8
2
SENSE
+V
IN
MEMORY
V+
D
2
1
V
OUT
470k
470k
20
+V
LP2951
#1
IN
1μF
5
3.6V
V
2
1
7
OUT
+
ERROR
5
NICAD
V
OUT
FB
ERROR
GND
4
R
1
LP2951
27kΩ
3
EARLY WARNING
RESET
D
D
3
1μF
2.7MΩ
4
SD
RESET
R
GND
4
Q1
3
8
2
330kΩ
μP
SENSE
+V
IN
MAIN
OUTPUT
1
V
V
DO
OUT
LP2951
#2
+
LATCH-OFF WHEN ERROR FLAG OCCURS
5
SD
ERROR
1μf
GND
4
• EARLY WARNING FLAG ON LOW INPUT VOLTAGE
• MAIN OUTPUT LATCHES OFF AT LOWER INPUT VOLTAGES
• BATTERY BACKUP ON AUXILIARY OUTPUT
OPERATION: REG. #1’S VOUT IS PROGRAMMED ONE DIODE DROP ABOVE 5V.
ITS ERROR FLAG BECOMES ACTIVE WHEN VIN ≤ 5.7V. WHEN V IN DROPS
BELOW 5.3V, THE ERROR FLAG OF REG. #2 BECOMES ACTIVE AND VIA Q1
LATCHES THE MAIN OUTPUT OFF. WHEN VIN AGAIN EXCEEDS 5.7V REG. #1
IS BACK IN REGULATION AND THE EARLY WARNING SIGNAL RISES,
UNLATCHING REG. #2 VIA D3.
REGULATOR WITH EARLY WARNING
AND AUXILIARY OUTPUT
+5V
8
2
20mA
4.7mA
4
+V
SENSE
39kΩ
IN
8
+V
+
= 5V
OUTPUT*
5
1
7
OUT
5
V
1
OUT
ERROR
LP2951
V
IN
RESET
1μF
1
7
V
OUT
FB
1N
C+– 4
3
4001
FB
SD
LP2951
4
0.1μF
GND
4
TAP
6
2
39kΩ
* HIGH FOR
GND
4
I
< 3.5mA
L
360
1N457
+
100
kΩ
6V
100kΩ
1%
1%
1%
–
MIN. VOLTAGE 4V
LEAD-
ACID
C1
+
<5.8V**
<6.0V**
<6.2V**
OPEN CIRCUIT DETECTOR FOR 4 mA
TO 20 mA CURRENT LOOP
BATTERY
1
100kΩ
100kΩ
–
kΩ
C2
+
C1-C4
LP339
1
–
kΩ
C3
+
10kΩ
R
3
1% 20kΩ
C1 TO C4 ARE COMPARATORS (LP339 OR EQUIVALENT)
*OPTIONAL LATCH OFF WHEN DROP OUT OCCURS. ADJUST R3 FOR C2
SWITCHING WHEN V IS 6.0V
IN
**OUTPUTS GO LOW WHEN V DROPS BELOW DESIGNATED THRESHOLDS.
IN
REGULATOR WITH
STATE-OF-CHARGE INDICATOR
2017 Microchip Technology Inc.
DS20005736A-page 3
LP2951
+
6V
120kΩ
FB
1.5 kΩ**
1N457
SEALED
LEAD-
ACID
8
+V
IN
BATTERY
SOURCE
LM385
1
2
MAIN V+
V
OUT
–
LP2951
SENSE
≈ 400 kΩ*
FOR 5.5V
MEMORY V+
20Ω
3
SD
100 kΩ
+
GND
4
1 μF
+
NI-CAD
* Sets disconnect voltage
** Sets disconnect hysteresis
BACKUP
BATTERY
For values shown, Regulator shuts down when VIN < 5.5V and turns on again at 6.0V. Current drain in disconnected mode is 150 μA.
LOW BATTERY DISCONNECT
+V
IN
8
10 kΩ
+V
IN
5° PRE-SHUTDOWN FLAG
5
1
AUX. SHUTDOWN
INPUT
3
ERROR
LP2951
SD
OFF
VOUT
ON
EXTERNAL CIRCUIT
PROTECTED FROM
OVER TEMPERATURE
(V+ GOES OFF WHEN
TEMP.> 125°)
GND
4
FB
7
OR
+
TEMP. LM34 OR
RELAY
SENSOR
LM35
–
8.2 kΩ
LM34 for 125°F Shutdown
LM35 for 125°C Shutdown
SYSTEM OVER TEMPERATURE
PROTECTION CIRCUIT
DS20005736A-page 4
2017 Microchip Technology Inc.
LP2951
1.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings † ††
Power Dissipation ..................................................................................................................................Internally Limited
Lead Temperature (soldering, 5 sec.) .....................................................................................................................260°C
Storage Temperature .............................................................................................................................–65°C to +150°C
Operating Junction Temperature Range(Note 1)
LP2951...................................................................................................................................................–40°C to +125°C
Input Supply Voltage .................................................................................................................................... –0.3 to +30V
Feedback Input Voltage(Note 2, 3) ............................................................................................................. –1.5 to +30V
Shutdown Input Voltage(Note 2) .................................................................................................................. –0.3 to +30V
Error Comparator Output Voltage(Note 2) ................................................................................................... –0.3 to +30V
† Notice: Boldface limits apply at temperature extremes.
†† Notice: If Military/Aerospace specified devices are required, contact your local representative/distributor for
availability and specifications.
Note 1: The thermal resistance of the 8-pin DIP package is 105°C/W junction-to-ambient when soldered directly to
a PC board. Junction-to-ambient thermal resistance for the SOIC (M) package is 160°C/W.
2: May exceed input supply voltage.
3: When used in dual-supply systems where the output terminal sees loads returned to a negative supply, the
output voltage should be diode-clamped to ground.
ELECTRICAL CHARACTERISTICS
Electrical Characteristics: Unless otherwise indicated, TA = +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
4.975
4.950
4.802
5.000
5.000
4.850
5.025
5.050
4.899
V
V
V
LP2951-02 (±0.5%)
LP2951-03 (±1%)
LP2951-4.8 (±1%)
Output Voltage
TJ = 25°C
Note 1: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
2: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle.
Changes in output voltage due to heating effects are covered in the specification for thermal regulation.
3: Line regulation for the LP2951 is tested at 150°C for IL = 1 mA. For IL = 100 ꢀA and TJ = 125°C, line regu-
lation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus
temperature and load current.
4: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV
below its nominal value measured at 1V differential. At very low values of programmed output voltage, the
minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
5: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN
30V (1.25W pulse) for t = 10 ms.
=
6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the
nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage
change, multiply by the error amplifier gain = VOUT/VREF =(R1 + R2)/R2. For example, at a programmed
output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x
5V/1.235V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the drop-
out warning occurring at typically 5% below nominal, 7.5% guaranteed.
7: VREF ≤ VOUT ≤ (VIN – 1 V), 2.3V ≤ VIN ≤ 30V, 100 ꢀA < IL ≤ 100 mA, TJ ≤ TJMAX
.
8: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
9: VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, with Feedback pin tied to 5V Tap.
2017 Microchip Technology Inc.
DS20005736A-page 5
LP2951
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Characteristics: Unless otherwise indicated, TA = +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
4.950
4.925
4.777
4.940
4.900
4.753
—
—
—
—
—
—
5.050
5.075
4.872
5.060
5.100
4.947
V
V
V
V
V
V
LP2951-02 (±0.5%)
LP2951-03 (±1%)
LP2951-4.8 (±1%)
LP2951-02 (±0.5%)
LP2951-03 (±1%)
LP2951-4.8 (±1%)
Output Voltage
–25°C ≤ TJ ≤ +85°C
Output Voltage
Over Full Temperature
Range
–40°C to +125°C
LP2951-02 (±0.5%), 100 ꢀA
≤ IL ≤ 100 mA, TJ ≤ TJ(max)
4.930
4.880
4.733
—
—
—
—
20
50
50
5.070
5.120
4.967
100
V
V
V
Output Voltage
Over Load Variation
LP2951-03 (±1%), 100 ꢀA ≤
IL ≤ 100 mA, TJ ≤ TJ(max)
LP2951-4.8 (±1%), 100 ꢀA ≤
IL ≤ 100 mA, TJ ≤ TJ(max)
ppm/
°C
LP2951-02 (±0.5%), Note 1
LP2951-03 (±1%), Note 1
LP2951-4.8 (±1%), Note 1
Output Voltage
Temperature Coefficient
ppm/
°C
—
150
ppm/
°C
—
150
Note 1: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
2: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle.
Changes in output voltage due to heating effects are covered in the specification for thermal regulation.
3: Line regulation for the LP2951 is tested at 150°C for IL = 1 mA. For IL = 100 ꢀA and TJ = 125°C, line regu-
lation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus
temperature and load current.
4: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV
below its nominal value measured at 1V differential. At very low values of programmed output voltage, the
minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
5: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN
30V (1.25W pulse) for t = 10 ms.
=
6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the
nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage
change, multiply by the error amplifier gain = VOUT/VREF =(R1 + R2)/R2. For example, at a programmed
output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x
5V/1.235V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the drop-
out warning occurring at typically 5% below nominal, 7.5% guaranteed.
7:
VREF ≤ VOUT ≤ (VIN – 1 V), 2.3V ≤ VIN ≤ 30V, 100 ꢀA < IL ≤ 100 mA, TJ ≤ TJMAX.
8: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
9:
VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, with Feedback pin tied to 5V Tap.
DS20005736A-page 6
2017 Microchip Technology Inc.
LP2951
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Characteristics: Unless otherwise indicated, TA = +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
0.03
—
0.10
0.20
0.20
0.40
0.20
0.40
0.10
0.20
0.20
0.30
0.20
0.30
80
%
%
LP2951-02 (±0.5%), Note 2,
3
0.04
—
%
Line Regulation
LP2951-03 (±1%), Note 2, 3
LP2951-4.8 (±1%), Note 2, 3
%
0.04
—
%
%
0.04
—
%
LP2951-02 (±0.5%), Note 2,
100 ꢀA ≤ IL ≤ 100 mA
%
0.10
—
%
LP2951-03 (±1%), Note 2,
100 ꢀA ≤ IL ≤ 100 mA
Load Regulation
%
0.10
—
%
LP2951-4.8 (±1%), Note 2,
100 ꢀA ≤ IL ≤ 100 mA
%
50
mV
mV
mV
mV
ꢀA
ꢀA
mA
mA
Note 4, IL = 100 ꢀA
Note 4, IL = 100 mA
IL = 100 ꢀA
—
150
450
600
150
200
12
Dropout Voltage
Ground Current
380
—
100
—
8
IL = 100 mA
—
14
Note 1: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
2: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle.
Changes in output voltage due to heating effects are covered in the specification for thermal regulation.
3: Line regulation for the LP2951 is tested at 150°C for IL = 1 mA. For IL = 100 ꢀA and TJ = 125°C, line regu-
lation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus
temperature and load current.
4: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV
below its nominal value measured at 1V differential. At very low values of programmed output voltage, the
minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
5: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN
30V (1.25W pulse) for t = 10 ms.
=
6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the
nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage
change, multiply by the error amplifier gain = VOUT/VREF =(R1 + R2)/R2. For example, at a programmed
output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x
5V/1.235V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the drop-
out warning occurring at typically 5% below nominal, 7.5% guaranteed.
7:
VREF ≤ VOUT ≤ (VIN – 1 V), 2.3V ≤ VIN ≤ 30V, 100 ꢀA < IL ≤ 100 mA, TJ ≤ TJMAX.
8: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
9:
VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, with Feedback pin tied to 5V Tap.
2017 Microchip Technology Inc.
DS20005736A-page 7
LP2951
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Characteristics: Unless otherwise indicated, TA = +25°C
Parameters
Dropout Current
Sym.
Min.
Typ.
Max.
Units
Conditions
250
310
ꢀA
ꢀA
—
180
VIN = 4.5V, IL = 100 ꢀA
220
220
mA
mA
Current Limit
—
160
VOUT = 0V
Thermal Regulation
—
—
0.05
430
0.20
—
%/W Note 5
ꢀVRMS 10 Hz to 100 kHz, CL = 1 ꢀF
10 Hz to 100 kHz,
ꢀVRMS
—
160
—
CL = 200 ꢀF
Output Noise
10 Hz to 100 kHz,
CL = 3.3 ꢀF,
0.01 ꢀF bypass Feedback to
—
100
—
ꢀVRMS
Output
1.220
1.200
1.210
1.200
1.210
1.200
1.190
1.185
1.185
1.235
—
1.25
V
LP2951-02 (±0.5%)
V
1.260
1.260
1.270
1.260
1.270
1.270
1.285
1.285
1.235
—
V
Reference Voltage
Reference Voltage
LP2951-03 (±1%)
V
1.235
—
V
LP2951-4.8 (±1%)
V
—
V
V
V
LP2951-02 (±0.5%), Note 7
LP2951-03 (±1%), Note 7
LP2951-4.8 (±1%), Note 7
—
—
Note 1: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
2: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle.
Changes in output voltage due to heating effects are covered in the specification for thermal regulation.
3: Line regulation for the LP2951 is tested at 150°C for IL = 1 mA. For IL = 100 ꢀA and TJ = 125°C, line regu-
lation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus
temperature and load current.
4: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV
below its nominal value measured at 1V differential. At very low values of programmed output voltage, the
minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
5: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN
30V (1.25W pulse) for t = 10 ms.
=
6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the
nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage
change, multiply by the error amplifier gain = VOUT/VREF =(R1 + R2)/R2. For example, at a programmed
output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x
5V/1.235V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the drop-
out warning occurring at typically 5% below nominal, 7.5% guaranteed.
7:
VREF ≤ VOUT ≤ (VIN – 1 V), 2.3V ≤ VIN ≤ 30V, 100 ꢀA < IL ≤ 100 mA, TJ ≤ TJMAX.
8: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
9:
VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, with Feedback pin tied to 5V Tap.
DS20005736A-page 8
2017 Microchip Technology Inc.
LP2951
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Characteristics: Unless otherwise indicated, TA = +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
—
—
—
—
—
20
—
20
50
50
40
60
—
—
—
Feedback Bias Current
nA
—
ppm/°C LP2951-02 (±0.5%), Note 8
ppm/°C LP2951-03 (±1%), Note 8
ppm/°C LP2951-4.8 (±1%), Note 8
Reference Voltage
Feedback Bias Current
Temperature Coefficient
—
0.1
—
nA/°C
—
—
—
—
40
25
—
—
—
0.01
—
1.00
2.00
250
400
—
ꢀA
Output Leakage Current
Output Low Voltage (Flag)
Upper Threshold Voltage
VOH = 30V
ꢀA
150
—
mV
VIN = 4.5V, IOL = 200ꢀA
mV
60
mV
Note 6
mV
—
75
—
15
95
mV
Lower Threshold Voltage
Hysteresis
Note 6
mV
140
—
mV
Note 6
Note 1: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
2: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle.
Changes in output voltage due to heating effects are covered in the specification for thermal regulation.
3: Line regulation for the LP2951 is tested at 150°C for IL = 1 mA. For IL = 100 ꢀA and TJ = 125°C, line regu-
lation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus
temperature and load current.
4: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV
below its nominal value measured at 1V differential. At very low values of programmed output voltage, the
minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
5: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN
30V (1.25W pulse) for t = 10 ms.
=
6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the
nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage
change, multiply by the error amplifier gain = VOUT/VREF =(R1 + R2)/R2. For example, at a programmed
output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x
5V/1.235V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the drop-
out warning occurring at typically 5% below nominal, 7.5% guaranteed.
7:
VREF ≤ VOUT ≤ (VIN – 1 V), 2.3V ≤ VIN ≤ 30V, 100 ꢀA < IL ≤ 100 mA, TJ ≤ TJMAX.
8: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
9:
VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, with Feedback pin tied to 5V Tap.
2017 Microchip Technology Inc.
DS20005736A-page 9
LP2951
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Characteristics: Unless otherwise indicated, TA = +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
—
—
1.3
—
—
0.7
—
V
V
V
V
V
V
V
V
V
LP2951-02 (±0.5%)
Low
2.0
—
—
High
1.3
—
—
LP2951-03 (±1%)
Input Logic Voltage
—
0.7
—
Low
2.0
—
—
High
1.3
—
—
LP2951-4.8 (±1%)
—
0.7
—
Low
2.0
—
High
Note 1: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
2: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle.
Changes in output voltage due to heating effects are covered in the specification for thermal regulation.
3: Line regulation for the LP2951 is tested at 150°C for IL = 1 mA. For IL = 100 ꢀA and TJ = 125°C, line regu-
lation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus
temperature and load current.
4: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV
below its nominal value measured at 1V differential. At very low values of programmed output voltage, the
minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
5: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN
30V (1.25W pulse) for t = 10 ms.
=
6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the
nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage
change, multiply by the error amplifier gain = VOUT/VREF =(R1 + R2)/R2. For example, at a programmed
output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x
5V/1.235V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the drop-
out warning occurring at typically 5% below nominal, 7.5% guaranteed.
7:
VREF ≤ VOUT ≤ (VIN – 1 V), 2.3V ≤ VIN ≤ 30V, 100 ꢀA < IL ≤ 100 mA, TJ ≤ TJMAX.
8: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
9:
VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, with Feedback pin tied to 5V Tap.
DS20005736A-page 10
2017 Microchip Technology Inc.
LP2951
ELECTRICAL CHARACTERISTICS (CONTINUED)
Electrical Characteristics: Unless otherwise indicated, TA = +25°C
Parameters
Sym.
Min.
Typ.
Max.
Units
Conditions
—
—
—
—
—
—
30
—
50
100
600
700
10
ꢀA
ꢀA
ꢀA
ꢀA
ꢀA
ꢀA
VSHUTDOWN = 2.4V
Shutdown Input Current
450
—
VSHUTDOWN = 30V
3
Regulator Output Current
in Shutdown
Note 9
—
20
Note 1: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
2: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle.
Changes in output voltage due to heating effects are covered in the specification for thermal regulation.
3: Line regulation for the LP2951 is tested at 150°C for IL = 1 mA. For IL = 100 ꢀA and TJ = 125°C, line regu-
lation is guaranteed by design to 0.2%. See Typical Performance Characteristics for line regulation versus
temperature and load current.
4: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV
below its nominal value measured at 1V differential. At very low values of programmed output voltage, the
minimum input supply voltage of 2V (2.3V over temperature) must be taken into account.
5: Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipa-
tion is applied, excluding load or line regulation effects. Specifications are for a 50 mA load pulse at VIN
30V (1.25W pulse) for t = 10 ms.
=
6: Comparator thresholds are expressed in terms of a voltage differential at the Feedback terminal below the
nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage
change, multiply by the error amplifier gain = VOUT/VREF =(R1 + R2)/R2. For example, at a programmed
output voltage of 5V, the Error output is guaranteed to go low when the output drops by 95 mV x
5V/1.235V = 384 mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the drop-
out warning occurring at typically 5% below nominal, 7.5% guaranteed.
7:
VREF ≤ VOUT ≤ (VIN – 1 V), 2.3V ≤ VIN ≤ 30V, 100 ꢀA < IL ≤ 100 mA, TJ ≤ TJMAX.
8: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by
the total temperature range.
9:
VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, with Feedback pin tied to 5V Tap.
2017 Microchip Technology Inc.
DS20005736A-page 11
LP2951
TEMPERATURE SPECIFICATIONS (Note 1)
Parameters
Temperature Ranges
Sym.
Min.
Typ.
Max.
Units
Conditions
Lead Temperature Range
—
TJ
TA
—
260
—
—
°C
°C
°C
Junction Operating Temperature
Storage Temperature Range
Package Thermal Resistances
Thermal Resistance, DIP Package
–40
–65
+125
+125
—
JA
JC
JA
JC
—
—
—
—
105
40
—
—
—
—
°C/W Soldered directly to a PC
board
°C/W
Thermal Resistance, SOIC Package
Typically mounting on a
°C/W 1'' square copper-clad
FR4 circuit board
160
25
°C/W
Note 1: The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable
junction temperature and the thermal resistance from junction to air (i.e., TA, TJ, JA). Exceeding the
maximum allowable power dissipation will cause the device operating junction temperature to exceed the
maximum +125°C rating. Sustained junction temperatures above +125°C can impact the device reliability.
DS20005736A-page 12
2017 Microchip Technology Inc.
LP2951
2.0
TYPICAL PERFORMANCE CURVES
Note: The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
160
140
120
100
80
10
RL = 50
Ω
1
60
0.1
40
20
0.01
0
0.1
1
10
150
0
1
2
3
4
5
6
7
8 9 10
LOAD CURRENT (mA)
INPUT VOLTAGE (V)
FIGURE 2-1:
Quiescent Current.
FIGURE 2-4:
Input Current.
6
5.06
5.04
5.02
5.00
4.98
4.96
4.94
5
4
RL = 50kΩ
3
2
RL = 50
Ω
0.2%
1
0
-75 -50 -25 0 25 50 75 100125 150
TEMPERATURE (°C)
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
FIGURE 2-2:
Dropout Characteristics.
FIGURE 2-5:
Output Voltage vs.
Temperature of 3 Representative Units.
320
280
240
250
225
200
175
150
125
100
75
RL = 50kΩ
IL = 1 mA
IL = 0
200
160
RL
=
∞
120
80
40
0
50
25
0
0
1
2
3
4
5
6
7
8
9 10
0
1
2
3
4
5
6
7
8
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
FIGURE 2-3:
Input Current.
FIGURE 2-6:
Ground Current.
2017 Microchip Technology Inc.
DS20005736A-page 13
LP2951
.
170
160
150
140
240
220
V
IN = 6V
IL = 100 μA
130
120
110
100
200
180
-75 -50 -25 0 25 50 75 100 125 150
TEMPERATURE (°C)
-75 -50 -25 0 25 50 75 100 125 150
TEMPERATURE (°C)
FIGURE 2-7:
Quiescent Current.
FIGURE 2-10:
Short Circuit Current.
600
500
16
12
8
IL = 100 mA
400
300
100
50
V
IN = 6V
IL = 100 mA
IL = 100 μA
0
4
-75 -50 -25 0 25 50 75 100125 150
TEMPERATURE (°C)
-75 -50 -25 0 25 50 75 100125 150
TEMPERATURE (°C)
FIGURE 2-11:
Dropout Voltage.
FIGURE 2-8:
Ground Current.
16
500
400
300
200
100
14
12
10
8
IL = 100 mA
6
T = 25 °C
J
4
2
0
0
0
1
2
3
4
5
6
7
8
100 μA 1 mA
10 mA
100 mA
INPUT VOLTAGE (V)
OUTPUT CURRENT
FIGURE 2-12:
Dropout Voltage.
FIGURE 2-9:
Ground Current.
DS20005736A-page 14
2017 Microchip Technology Inc.
LP2951
8
6
4
2
2.2
2.1
2.0
1.9
1.8
VOUT = 5V
HYSTERESIS
0
1.7
1.6
PULLUP RESISTOR TO
SEPARATE 5V SUPPLY
-2
0
1
2
3
4
5
-75 -50 -25 0 25 50 75 100125 150
INPUT VOLTAGE (V)
TEMPERATURE (°C)
FIGURE 2-13:
Minimum Operating Voltage.
FIGURE 2-16:
Error Comparator Output.
20
10
0
2.5
2.0
1.5
1.0
0.5
0.0
T = 125°C
A
T = 25°C
A
-10
-20
-30
T = -55°C
A
0.1
0.3
0.5 0.7
0.9
-75 -50 -25 0 25 50 75 100125 150
TEMPERATURE (°C)
OUTPUT LOW VOLTAGE (V)
FIGURE 2-14:
Feedback Bias Current.
FIGURE 2-17:
Comparator Sink Current.
50
0
100
PIN 7 DRIVEN BY EXTERNAL
mV
SOURCE (REGULATOR RUN
OPEN LOOP)
50
mV
-50
0
T = 125°C
A
-50
mV
CL= 1 μF
IL = 1 mA
VOUT = 5V
-100
8V
-150
-200
-250
T = 25°C
A
6V
4V
T = –55°C
A
0
200 400
μs)
600 800
-2.0 -1.5 -1.0 -0.5
0
0.5 1.0
TIME (
FEEDBACK VOLTAGE (V)
FIGURE 2-15:
Feedback Pin Current.
FIGURE 2-18:
Line Transient Response.
2017 Microchip Technology Inc.
DS20005736A-page 15
LP2951
250
200
150
100
50
10
5
I0 = 100 μA
I0 = 1 mA
2
1
I0 = 100 mA
0
0.5
-50
-100
0.2
0.1
0.05
VOUT = 5V
CL= 1 μF
CL= 1 μF
VOUT = 5V
100
mA
100
μA
0.02
0.01
10 100
1K 10K 100K 1M
FREQUENCY (Hz)
0
1
2
3
4
5
TIME (ms)
FIGURE 2-19:
Load Transient Response.
FIGURE 2-22:
Output Impedance.
90
80
70
60
50
80
60
40
20
0
-20
-40
-60
IL = 0
CL= 10 μF
VOUT = 5V
40 CL = 1 μF
IL = 100 μA
V
IN = 6V
100
mA
100
μA
30
20
V
OUT = 5V
101
102 103 104 10
106
0
4
8
12 16 20
TIME (ms)
FREQUENCY (Hz)
FIGURE 2-23:
Ripple Rejection.
FIGURE 2-20:
Load Transient Response.
7
6
5
90
80
LL= 1 μF
CL = 1 μF
V
IN = 6V
70
60
4
3
2
1
0
2
0
IL = 1 mA
V
OUT = 5V
IL = 10 mA
VIN = 8V
50
40
30
20
CL = 10 μF VOUT = 5V
IL = 10 mA
102 103 104 105 106
FREQUENCY (Hz)
-2
101
-100
100
300
500
700
TIME (μs)
FIGURE 2-21:
Enable Transient.
FIGURE 2-24:
Ripple Rejection.
DS20005736A-page 16
2017 Microchip Technology Inc.
LP2951
80
70
60
50
40
30
20
10
IL = 50 μA
IL = 100 mA
CL = 1 μF
1.8
1.6
1.4
1.2
1.0
0.8
0.6
VIN = 6V
VOUT = 5V
101 102 103 104 105 106
FREQUENCY (Hz)
-75 -50-25
0 25 50 75 100125 150
TEMPERATURE (°C)
FIGURE 2-25:
Ripple Rejection.
FIGURE 2-28:
Shutdown Threshold
Voltage.
3.5
3.0
2.5
2.0
1.5
1.0
30
IL = 100 mA
CL = 1 μF
25
20
15
10
5
IL = 100 μA
TJ = 150°C
IL = 1 mA
CL = 220 μF
0
CL
=
3.3 μF
10
5
0
-5
IL = 100 μA
TJ = 125°C
0.01 μF
0.5 BYPASS
PIN 1 TO
PIN 7
-10
5
10
15
20
25
30
0.0
102
103
104
105
INPUT VOLTAGE (V)
FREQUENCY (Hz)
FIGURE 2-26:
Output Noise.
FIGURE 2-29:
Line Regulation.
400
300
200
100
0
5
4
2
0
-2
1
1.25W
0
-1
-75 -50-25
0 25 50 75 100125 150
30
TIME (μs)
40
0
10
20
50
TEMPERATURE (°C)
FIGURE 2-27:
Divider Resistance.
FIGURE 2-30:
Thermal Response.
2017 Microchip Technology Inc.
DS20005736A-page 17
LP2951
3.0
PIN DESCRIPTIONS
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1:
LP2951
DIP AND SOIC PIN FUNCTION TABLE
Symbol
Description
1
2
3
4
5
6
7
8
VOUT
Regulated voltage output.
SENSE Output Voltage Sense.
SHDN
GND
Shutdown Input.
Ground Terminal.
ERROR Error Output.
5V TAP Internal Resistor Divider for 5V Output.
FB
Voltage Feedback Input.
VIN
Unregulated Supply Voltage.
DS20005736A-page 18
2017 Microchip Technology Inc.
LP2951
output. The out of regulation condition may be due
either to low input voltage, current limiting, or thermal
limiting.
4.0
4.1
APPLICATION INFORMATION
External Capacitors
Figure 4-1 is a timing diagram depicting the ERROR
signal and the regulated output voltage as the LP2951
input is ramped up and down. The ERROR signal
becomes valid (low) at about 1.3V input. It goes high at
A 1.0 ꢀF (or greater) capacitor is required between the
LP2951 output and ground to prevent oscillations due
to instability. Most types of tantalum or aluminum
electrolytics will be adequate; film types will work, but
are costly and therefore not recommended. Many
aluminum electrolytics have electrolytes that freeze at
about –30°C, so solid tantalum capacitors are
recommended for operation below –25°C. The
important parameters of the capacitor are an effective
series resistance of about 5Ω or less and a resonant
frequency above 500 kHz. The value of this capacitor
may be increased without limit.
about 5V input (the input voltage at which VOUT
=
4.75V). Since the LP2951’s dropout voltage is
load-dependent (see curve in Typical Performance
Curves), the input voltage trip point (about 5V) will vary
with the load current. The output voltage trip point
(approximately 4.75V) does not vary with load.
The error comparator has an open-collector output
which requires an external pull-up resistor. Depending
on system requirements, this resistor may be returned
to the 5V output or some other supply voltage. In
determining a value for this resistor, note that while the
output is rated to sink 400 ꢀA, this sink current adds to
battery drain in a low battery condition. Suggested
values range from 100 kΩ to 1 MΩ. The resistor is not
required if this output is unused.
At lower values of output current, less output
capacitance is required for output stability. The
capacitor can be reduced to 0.33 ꢀF for current below
10 mA or 0.1 ꢀF for currents below 1 mA. Using the
8-pin versions at voltages below 5V runs the error
amplifier at lower gains so that more output
capacitance is needed. For the worst-case situation of
a 100 mA load at 1.23V output (Output shorted to
Feedback) a 3.3 ꢀF (or greater) capacitor should be
used.
4.3
Programming the Output Voltage
The LP2951 may be pin-strapped for 5V output voltage
using its internal voltage divider, by tying Pin 1 (VOUT
)
When the 5V Tap pin and Feedback pin are connected
together for 5V output voltage, the LP2951 will remain
stable and in regulation with no load in addition to the
internal voltage divider, unlike many other voltage
regulators. This is especially important in CMOS RAM
keep-alive applications. When setting the output
voltage of the LP2951 with external resistors, a
minimum load of 1 ꢀA is recommended.
and Pin 2 (SENSE) together, as well as tying Pin 7
(Feedback) and Pin 6 (5V TAP) together. Alternatively,
it may be programmed for any output voltage between
its 1.235V reference and its 30V maximum rating. An
external pair of resistors is required, as shown in
Figure 4-2.
The complete equation for the output voltage is:
A 0.1 ꢀF capacitor should be placed from the LP2951
input to ground if there is more than 10 inches of wire
between the input and the AC filter capacitor or if a
battery is used as the input.
EQUATION 4-1:
Stray capacitance to the LP2951 Feedback terminal
(pin 7) can cause instability. This may especially be a
problem when using high value external resistors to set
the output voltage. Adding a 100 pF capacitor between
Output and Feedback and increasing the output
capacitor to at least 3.3 ꢀF will remedy this.
R
1
V OUT = V REF
1 + ----- + IFBR2
R2
Where:
VREF
IFB
=
=
the nominal 1.235 reference voltage
the feedback pin bias current,
nominally 20 nA
4.2
Error Detection Comparator
Output
The minimum recommended load current of 1 ꢀA
forces an upper limit of 1.2 MΩ on the value of R2, if the
regulator must work with no load (a condition often
found in CMOS in standby), IFB will produce a 2%
typical error in VOUT which may be eliminated at room
temperature by trimming R1. For better accuracy,
choosing R2 = 100 kΩ reduces this error to 0.17%
while increasing the resistor program current to 12 ꢀA.
Since the LP2951 typically draws 60 ꢀA at no load with
Pin 2 open-circuited, this is a small price to pay.
A logic low output will be produced by the comparator
whenever the LP2951 output falls out of regulation by
more than approximately 5%. This figure is the
comparator’s built-in offset of about 60mV divided by
the 1.235V reference voltage. (Refer to the block
diagram on Page 1). This trip level remains “5% below
normal” regardless of the programmed output voltage
of the LP2951. For example, the error flag trip level is
typically 4.75V for a 5V output or 11.4V for a 12V
2017 Microchip Technology Inc.
DS20005736A-page 19
LP2951
4.4
Reducing Output Noise
In reference applications it may be advantageous to
reduce theAC noise present at the output. One method
is to reduce the regulator bandwidth by increasing the
size of the output capacitor. This method is relatively
inefficient, as increasing the capacitor from 1ꢀF to
220 ꢀF only decreases the noise from 430 ꢀV to
160 ꢀVrms for a 100 kHz bandwidth at 5V output.
Noise can be reduced fourfold by a bypass capacitor
across R1, since it reduces the high frequency gain
from 4 to unity. Pick the resulting frequency from
Equation 4-2:
EQUATION 4-2:
1
CBYPASS = ----------------------------------
2R1 200Hz
or about 0.01 ꢀF. When doing this, the output capacitor
must be increased to 3.3 ꢀF to maintain stability. These
changes reduce the output noise from 430 ꢀV to
100 ꢀVrms for a100 kHz bandwidth at 5V output. With
the bypass capacitor added, noise no longer scales
with output voltage so that improvements are more
dramatic at higher output voltages.
4.75V
OUTPUT
VOLTAGE
*
*
NOT
NOT
VALID
ERROR
VALID
INPUT
5V
VOLTAGE
1.3V
* SEE APPLICATIONS INFORMATION
FIGURE 4-1:
ERROR Output Timing.
*SEE APPLICATIONS
INFORMATION
+V
IN
V
= V
R
R
OUT
REF
1
x (1 +
OUT
1.2 30V
)
100kΩ
8
V
2
V
IN
5
1
ERROR
OUTPUT
ERROR
V
OUT
LP2951
3
SHUTDOWN
INPUT
SD
3.3μF
R
1
100
pF
OFF
GND
FB
ON
4
7
1.23V
NOTE: PINS 2 AND 6 ARE LEFT OPEN
R
V
2
REF
FIGURE 4-2:
Adjustable Regulator.
DS20005736A-page 20
2017 Microchip Technology Inc.
LP2951
FEEDBACK
IN
R18
20 kΩ
Q15A
Q15B
Q24
Q26
Q25
OUT
Q9
Q3
Q1
Q4
Q7
SENSE
R11
18
R27
Q8
Q5
kΩ
R17
12 kΩ
182 kΩ
C1
20
pF
Q14
R11
20.6
kΩ
Q17
Q6
Q16
5V TAP
R28
60 kΩ
Q2
10
Q20
R1
20 kΩ
Q22
R10
150
kΩ
R8
31.4
kΩ
Q42
Q21
Q23
C2
R2
50 kΩ
40 pF
R15
100 kΩ
R9
27.8
kΩ
R5
180
kΩ
R6
140
kΩ
R12
110
kΩ
R14
350
kΩ
R13
100
kΩ
R16
30 kΩ
Q40
Q13
Q12
R17
10 Ω
Q41
Q11
Q29
R30
Q18
Q19
30
kΩ
Q28
R3
50 kΩ
R4
13 kΩ
R21 8Ω
Q30 Q31
SHDN
50 kΩ
R23 60 kΩ
R22
150
kΩ
Q37
Q36
R24
50 kΩ
Ω
10 kΩ
ERROR
Q38
Q34
R26
50 kΩ
R25
2.8 kΩ
GND
Q39
FIGURE 4-3:
Schematic Diagram.
2017 Microchip Technology Inc.
DS20005736A-page 21
LP2951
5.0
5.1
PACKAGING INFORMATION
Package Marking Information
8-Pin SOIC*
Example
YYWW
XXXXXX
XXXX
1613
LP2951
02YM
8-Pin Plastic DIP*
Example
1016
LP2951
03YN
YYWW
XXXXXX
XXXX
Legend: XX...X Product code or customer-specific information
Y
Year code (last digit of calendar year)
YY
WW
NNN
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
e
3
Pb-free JEDEC® designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator (
can be found on the outer packaging for this package.
*
e
3
)
●, ▲, ▼ Pin one index is identified by a dot, delta up, or delta down (triangle
mark).
Note: In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information. Package may or may not include
the corporate logo.
Underbar (_) and/or Overbar (‾) symbol may not be to scale.
DS20005736A-page 22
2017 Microchip Technology Inc.
LP2951
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging.
2017 Microchip Technology Inc.
DS20005736A-page 23
LP2951
Note: For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging.
DS20005736A-page 24
2017 Microchip Technology Inc.
LP2951
APPENDIX A: REVISION HISTORY
Revision A (May 2017)
• Converted Micrel document LP2951 to Microchip
data sheet template DS20005736A.
• Minor grammatical text changes throughout.
2017 Microchip Technology Inc.
DS20005736A-page 25
LP2951
NOTES:
DS20005736A-page 26
2017 Microchip Technology Inc.
LP2951
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, contact your local Microchip representative or sales office.
Examples:
-X
PART NO.
Device
X
X
a)
b)
c)
LP2951-02YM:
LP2951-03YM:
LP2951-02YN:
100 mA Low-Dropout
Voltage Regulator,
0.5% Accuracy,
–40°C to +85°C (RoHS
Compliant)
Accuracy
Temperature
Range
Package
Device:
LP2951:
100 mA Low-Dropout Voltage Regulator
8LD SOIC
100 mA Low-Dropout
Voltage Regulator,
1.0% Accuracy,
–40°C to +85°C (RoHS
Compliant)
Accuracy:
02
03
=
=
0.5%
1.0%
Temperature
Range:
Y
=
–40C to +85C (RoHS Compliant)
8LD SOIC
100 mA Low-Dropout
Voltage Regulator,
0.5% Accuracy,
–40°C to +85°C (RoHS
Compliant)
Packages:
M
N
=
=
8-pin SOIC
8-pin DIP
8LD DIP
Note 1:
Tape and Reel identifier only appears in the
catalog part number description. This
identifier is used for ordering purposes and
is not printed on the device package. Check
with your Microchip Sales Office for package
availability with the Tape and Reel option.
2017 Microchip Technology Inc.
DS20005736A-page 27
LP2951
NOTES:
DS20005736A-page 28
2017 Microchip Technology Inc.
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device
applications and the like is provided only for your convenience
and may be superseded by updates. It is your responsibility to
ensure that your application meets with your specifications.
MICROCHIP MAKES NO REPRESENTATIONS OR
WARRANTIES OF ANY KIND WHETHER EXPRESS OR
IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION,
INCLUDING BUT NOT LIMITED TO ITS CONDITION,
QUALITY, PERFORMANCE, MERCHANTABILITY OR
FITNESS FOR PURPOSE. Microchip disclaims all liability
arising from this information and its use. Use of Microchip
devices in life support and/or safety applications is entirely at
the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims,
suits, or expenses resulting from such use. No licenses are
conveyed, implicitly or otherwise, under any Microchip
intellectual property rights unless otherwise stated.
Trademarks
The Microchip name and logo, the Microchip logo, AnyRate, AVR,
AVR logo, AVR Freaks, BeaconThings, BitCloud, CryptoMemory,
CryptoRF, dsPIC, FlashFlex, flexPWR, Heldo, JukeBlox, KEELOQ,
KEELOQ logo, Kleer, LANCheck, LINK MD, maXStylus,
maXTouch, MediaLB, megaAVR, MOST, MOST logo, MPLAB,
OptoLyzer, PIC, picoPower, PICSTART, PIC32 logo, Prochip
Designer, QTouch, RightTouch, SAM-BA, SpyNIC, SST, SST
Logo, SuperFlash, tinyAVR, UNI/O, and XMEGA are registered
trademarks of Microchip Technology Incorporated in the U.S.A.
and other countries.
ClockWorks, The Embedded Control Solutions Company,
EtherSynch, Hyper Speed Control, HyperLight Load, IntelliMOS,
mTouch, Precision Edge, and Quiet-Wire are registered
trademarks of Microchip Technology Incorporated in the U.S.A.
Adjacent Key Suppression, AKS, Analog-for-the-Digital Age, Any
Capacitor, AnyIn, AnyOut, BodyCom, chipKIT, chipKIT logo,
CodeGuard, CryptoAuthentication, CryptoCompanion,
CryptoController, dsPICDEM, dsPICDEM.net, Dynamic Average
Matching, DAM, ECAN, EtherGREEN, In-Circuit Serial
Programming, ICSP, Inter-Chip Connectivity, JitterBlocker,
KleerNet, KleerNet logo, Mindi, MiWi, motorBench, MPASM, MPF,
MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach,
Omniscient Code Generation, PICDEM, PICDEM.net, PICkit,
PICtail, PureSilicon, QMatrix, RightTouch logo, REAL ICE, Ripple
Blocker, SAM-ICE, Serial Quad I/O, SMART-I.S., SQI,
SuperSwitcher, SuperSwitcher II, Total Endurance, TSHARC,
USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA,
and ZENA are trademarks of Microchip Technology Incorporated
in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated in
the U.S.A.
Microchip received ISO/TS-16949:2009 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona; Gresham, Oregon and design centers in California
and India. The Company’s quality system processes and procedures
are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping
devices, Serial EEPROMs, microperipherals, nonvolatile memory and
analog products. In addition, Microchip’s quality system for the design
and manufacture of development systems is ISO 9001:2000 certified.
Silicon Storage Technology is a registered trademark of Microchip
Technology Inc. in other countries.
GestIC is a registered trademark of Microchip Technology
Germany II GmbH & Co. KG, a subsidiary of Microchip
Technology Inc., in other countries.
All other trademarks mentioned herein are property of their
respective companies.
© 2017, Microchip Technology Incorporated, All Rights Reserved.
ISBN: 978-1-5224-1711-8
2017 Microchip Technology Inc.
DS20005736A-page 29
Worldwide Sales and Service
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://www.microchip.com/
support
Asia Pacific Office
China - Xiamen
Tel: 86-592-2388138
Fax: 86-592-2388130
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Suites 3707-14, 37th Floor
Tower 6, The Gateway
Harbour City, Kowloon
China - Zhuhai
Tel: 86-756-3210040
Fax: 86-756-3210049
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
Hong Kong
Tel: 852-2943-5100
Fax: 852-2401-3431
India - Bangalore
Tel: 91-80-3090-4444
Fax: 91-80-3090-4123
Finland - Espoo
Tel: 358-9-4520-820
Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
Web Address:
www.microchip.com
France - Paris
Tel: 33-1-69-53-63-20
Fax: 33-1-69-30-90-79
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
China - Beijing
Tel: 86-10-8569-7000
Fax: 86-10-8528-2104
France - Saint Cloud
Tel: 33-1-30-60-70-00
India - Pune
Tel: 91-20-3019-1500
China - Chengdu
Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
Germany - Garching
Tel: 49-8931-9700
Germany - Haan
Austin, TX
Tel: 512-257-3370
Japan - Osaka
Tel: 81-6-6152-7160
Fax: 81-6-6152-9310
Boston
Tel: 49-2129-3766400
China - Chongqing
Tel: 86-23-8980-9588
Fax: 86-23-8980-9500
Westborough, MA
Tel: 774-760-0087
Fax: 774-760-0088
Japan - Tokyo
Tel: 81-3-6880- 3770
Fax: 81-3-6880-3771
Germany - Heilbronn
Tel: 49-7131-67-3636
China - Dongguan
Tel: 86-769-8702-9880
Germany - Karlsruhe
Tel: 49-721-625370
Chicago
Itasca, IL
Tel: 630-285-0071
Fax: 630-285-0075
Korea - Daegu
Tel: 82-53-744-4301
Fax: 82-53-744-4302
China - Guangzhou
Tel: 86-20-8755-8029
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
China - Hangzhou
Tel: 86-571-8792-8115
Fax: 86-571-8792-8116
Korea - Seoul
Dallas
Addison, TX
Tel: 972-818-7423
Fax: 972-818-2924
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
Germany - Rosenheim
Tel: 49-8031-354-560
China - Hong Kong SAR
Tel: 852-2943-5100
Fax: 852-2401-3431
Israel - Ra’anana
Tel: 972-9-744-7705
Malaysia - Kuala Lumpur
Tel: 60-3-6201-9857
Fax: 60-3-6201-9859
Detroit
Novi, MI
Tel: 248-848-4000
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
China - Nanjing
Tel: 86-25-8473-2460
Fax: 86-25-8473-2470
Malaysia - Penang
Tel: 60-4-227-8870
Fax: 60-4-227-4068
Houston, TX
Tel: 281-894-5983
Italy - Padova
Tel: 39-049-7625286
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Indianapolis
Noblesville, IN
Tel: 317-773-8323
Fax: 317-773-5453
Tel: 317-536-2380
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
China - Shanghai
Tel: 86-21-3326-8000
Fax: 86-21-3326-8021
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
Norway - Trondheim
Tel: 47-7289-7561
Los Angeles
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Mission Viejo, CA
Tel: 949-462-9523
Fax: 949-462-9608
Tel: 951-273-7800
Poland - Warsaw
Tel: 48-22-3325737
Taiwan - Hsin Chu
Tel: 886-3-5778-366
Fax: 886-3-5770-955
Romania - Bucharest
Tel: 40-21-407-87-50
China - Shenzhen
Tel: 86-755-8864-2200
Fax: 86-755-8203-1760
Taiwan - Kaohsiung
Tel: 886-7-213-7830
Raleigh, NC
Tel: 919-844-7510
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Taiwan - Taipei
Tel: 886-2-2508-8600
Fax: 886-2-2508-0102
New York, NY
Tel: 631-435-6000
Sweden - Gothenberg
Tel: 46-31-704-60-40
San Jose, CA
Tel: 408-735-9110
Tel: 408-436-4270
China - Xian
Tel: 86-29-8833-7252
Fax: 86-29-8833-7256
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Sweden - Stockholm
Tel: 46-8-5090-4654
Canada - Toronto
Tel: 905-695-1980
Fax: 905-695-2078
UK - Wokingham
Tel: 44-118-921-5800
Fax: 44-118-921-5820
DS20005736A-page 30
2017 Microchip Technology Inc.
11/07/16
相关型号:
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Fixed/Adjustable Positive LDO Regulator, 3.267V Min, 3.333V Max, 0.6V Dropout, PDSO8, SO-8
SEMTECH
LP2951-3.3TR
Fixed/Adjustable Positive LDO Regulator, 3.267V Min, 3.333V Max, 0.6V Dropout, PDSO8, SO-8
SEMTECH
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