MAX883MSA/PR [MAXIM]
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators; 5V / 3.3V或可调,低压差,低IQ , 200mA线性稳压器型号: | MAX883MSA/PR |
厂家: | MAXIM INTEGRATED PRODUCTS |
描述: | 5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators |
文件: | 总17页 (文件大小:361K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
19-0275; Rev 3; 9/08
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
General Description
Features
The MAX882/MAX883/MAX884 linear regulators maxi-
mize battery life by combining ultra-low supply currents
and low dropout voltages. They feature 200mA output
current capability at up to +125°C junction temperature
and come in a 1.5W SOIC package. The 1.5W package
(compared to 0.47W for standard SOIC packages)
allows a wider operating range for the input voltage and
output current. The MAX882/MAX883/MAX884 use a P-
channel MOSFET pass transistor to maintain a low 11µA
(15µA max) supply current from no-load to the full
200mA output. Unlike earlier bipolar regulators, there are
no PNP base current losses that increase with output
current. In dropout, the MOSFET does not suffer from
excessive base currents that occur when PNP transistors
go into saturation. Typical dropout voltages are 220mV
at 5V and 200mA, or 320mV at 3.3V and 200mA.
♦ Foldback Current Limiting
♦ High-Power (1.5W) 8-Pin SO Package
♦ Dual Mode Operation: Fixed or Adjustable
Output from 1.25V to 11V
♦ Large Input Range (2.7V to 11.5V)
♦ Internal 1.1Ω P-Channel Pass Transistor
Draws No Base Current
♦ Low 220mV Dropout Voltage at 200mA
Output Current
♦ 11µA (typ) Quiescent Current
♦ 1µA (max) Shutdown Mode or 7µA (typ)
Standby Mode
The MAX882 features a 7µA standby mode that disables
the output but keeps the reference, low-battery compara-
tor, and biasing circuitry alive. The MAX883/MAX884 fea-
ture a shutdown (OFF) mode that turns off all circuitry,
reducing supply current to less than 1µA. All three
devices include a low-battery-detection comparator, fold-
back current limiting, reverse-current protection, and
thermal-overload protection.
The output is preset at 3.3V for the MAX882/MAX884
and 5V for the MAX883. In addition, all devices employ
Dual Mode™ operation, allowing user-adjustable outputs
from 1.25V to 11V using external resistors. The input volt-
age supply range is 2.7V to 11.5V.
♦ Low-Battery Detection Comparator
♦ Reverse-Current Protection
♦ Thermal-Overload Protection
Ordering Information
PIN-
PACKAGE
PART
TEMP RANGE
MAX882CPA
MAX882CSA
MAX882C/D
MAX882EPA
MAX882ESA
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
8 PDIP
8 SO
Dice*
8 PDIP
8 SO
For low-dropout linear regulators with output currents up
to 500mA, refer to the MAX603/MAX604 data sheet.
Applications
Ordering Information continued at end of data sheet.
*Dice are tested at T = +25°C, DC parameters only.
J
Pagers and Cellular Phones
3.3V and 5V Regulators
**Contact factory for availability.
1.25V to 11V Adjustable Regulators
High-Efficiency Linear Regulators
Battery-Powered Devices
Portable Instruments
Typical Operating Circuit
ON/OFF
OFF (STBY)
Solar-Powered Instruments
Pin Configuration
OUTPUT
VOLTAGE
MAX882
MAX883
MAX884
TOP VIEW
IN
OUT
INPUT
VOLTAGE
LBI
1
2
3
4
8
7
6
5
LBI
LBO
SET
C
C
OUT
IN
OFF (STBY)
O.1μF
2.2μF
MAX882
MAX883
MAX884
SET
GND
BATTERY
GND
OUT
GND
IN
( ) ARE FOR MAX882.
( ) ARE FOR MAX882.
DIP/SO
Dual Mode is a trademark of Maxim Integrated Products.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim's website at www.maxim-ic.com.
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (IN or OUT to GND).......................-0.3V to +12V
Output Short-Circuit Duration ...............................................1min
Continuous Output Current...............................................300mA
LBO Output Current............................................................50mA
LBO Output Voltage and LBI,
High-Power SO (derate 18.75mW/°C above +70°C).......1.5W
CERDIP (derate 8.00mW/°C above +70°C).................640mW
Operating Temperature Ranges
MAX88_C_A........................................................0°C to +70°C
MAX88_E_A.....................................................-40°C to +85°C
Junction Temperature .....................................................+150°C
Storage Temperature Range.............................-65°C to +160°C
Lead Temperature (soldering, 10s) .................................+300°C
SET, STBY, OFF Input Voltages ............-0.3V to the greater of
(IN + 0.3V) or (OUT + 0.3V)
Continuous Power Dissipation (T = +70°C)
J
Plastic DIP (derate 9.09mW/°C above +70°C) ............727mW
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V = 6V (MAX883) or V = 4.3V (MAX882/MAX884), C
= 2.2µF, STBY or OFF = V , SET = GND, LBI = V , T = -40°C to
IN IN J
IN
IN
OUT
+85°C, unless otherwise noted. Typical values are at T = +25°C.) (Note 1)
J
PARAMETER
SYMBOL
CONDITIONS
MIN
2.7
2.9
3.0
TYP
MAX
11.5
11.5
11.5
UNITS
MAX88_C_A
MAX88_E_A
MAX88_MJA
SET = OUT, R =
L
Input Voltage Range
V
V
IN
1kΩ
I
= 100µA - 250mA,
J
OUT
4.75
4.65
3.15
3.07
5.00
3.30
5.25
5.35
3.45
3.53
0°C ≤ T ≤ +85°C
MAX883,
6.0V ≤ V ≤ 11.5V
IN
I
= 100µA - 250mA,
OUT
-40°C ≤ T ≤ +85°C
J
Output Voltage (Note 2)
V
V
OUT
I
= 100µA - 200mA,
J
OUT
0°C ≤ T ≤ +85°C
MAX882/MAX884,
4.3V ≤ V ≤ 11.5V
IN
I
= 100µA - 200mA,
OUT
-40°C ≤ T ≤ +85°C
J
MAX883C_A/E_A
MAX883MJA
60
30
100
150
I
= 1mA to
OUT
200mA
Load Regulation
ΔV
ΔV
mV
mV
mV
LDR
I
= 1mA to
OUT
MAX882, MAX884
100
150mA
Line Regulation
(V
+ 0.5V) < V < 11.5V, I = 10mA
OUT
10
40
220
440
320
640
15
LNR
OUT
IN
I
I
I
I
= 100mA
= 200mA
= 100mA
= 200mA
110
220
160
320
11
OUT
OUT
OUT
OUT
MAX883
Dropout Voltage (Note 3)
ΔV
DO
MAX882/MAX884
MAX88_C_A/E_A
MAX88_MJA
SET = OUT, V
6V
=
IN
30
Quiescent Current
I
µA
Q
MAX88_C_A/E_A
MAX88_MJA
15
25
V
= 11.5V
IN
40
2
_______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
ELECTRICAL CHARACTERISTICS (continued)
(V = 6V (MAX883) or V = 4.3V (MAX882/MAX884), C
= 2.2µF, STBY or OFF = V , SET = GND, LBI = V , T = -40°C to
IN
IN
OUT
IN IN J
+85°C, unless otherwise noted. Typical values are at T = +25°C.) (Note 1)
J
PARAMETER
SYMBOL
CONDITIONS
MAX882C_A/E_A
=
MIN
TYP
MAX
15
30
25
40
1
UNITS
7
STBY = 0, V
IN
6V, SET = OUT
MAX882MJA
MAX882C_A/E_A
MAX882MJA
MAX88_C_A
MAX88_E_A
MAX88_MJA
MAX88_C_A
MAX88_E_A
MAX88_MJA
STBY Quiescent Current (Note 4)
I
µA
Q STBY
10
STBY = 0, V
=
IN
11.5V, SET = OUT
0.01
OFF = 0, R = 1kΩ,
L
OFF Quiescent Current
I
µA
V
= 11.5V
5
Q OFF
IN
MAX883/MAX884
10
1
V
= 11.5V, SET =
IN
Minimum Load Current
I
3
µA
OUT(MIN)
OUT
10
V
V
< 0.8V
170
430
+160
10
OUT
OUT
Foldback Current Limit (Note 5)
ILIM
mA
> 0.8V and V - V
> 0.7V
IN
OUT
Thermal Shutdown Temperature
Thermal Shutdown Hysteresis
T
SD
°C
°C
ΔT
SD
V
V
= 4.5V
= 3.0V
MAX883_A
6
20
20
OUT
OUT
Reverse-Current-Protection
(Note 6)
ΔV
mV
RTH
MAX882_A,
MAX884_A
6
7
MAX882: V = 0, STBY = 0, V
= 3.0V
OUT
IN
Reverse Leakage Current
Startup Overshoot
I
µA
RVL
MAX883/MAX884: V = 0, OFF = 0, V
IN
= 3.0V
OUT
0.01
% of
V
R = 1kΩ, C
= 2.2µF
OSH
L
OUT
V
OUT
Time Required to Exit OFF or
STBY Modes
V
= 9V, R = 33Ω, OFF from 0 to V , 0%
IN L IN
T
200
µs
START
SET TH
to 95% of V
OUT
For internal feedback
For external feedback
65
65
30
Dual Mode SET Threshold
V
mV
150
1.16
1.12
0°C ≤ T ≤ +85°C
1.20
1.24
1.28
50
J
SET = OUT, R =
L
1kΩ
SET Reference Voltage
SET Input Leakage Current
LBI Threshold Voltage
V
V
nA
V
SET
-40°C ≤ T ≤ +85°C
J
I
V
= 1.5V or 0
0.01
1.20
SET
SET
0°C ≤ T ≤ +85°C
1.15
1.11
1.25
1.29
J
V
LBI signal falling
LBI
-40°C ≤ T ≤ +85°C
J
LBI Hysteresis
ΔV
7
mV
nA
LBI
LBI Input Leakage Current
I
V
= 1.5V
0.01
50
LBI
LBI
I
sink = 1.2mA, V
= 1V, 3V < V
<
IN
LBO
LBI
LBO Output Low Voltage
V
90
250
mV
µA
LBOL
11.5V, SET = OUT
LBO Output Leakage Current
I
V
= V , V = V
0.01
0.01
0.1
1
BLO LKG
LBI
IN LBO
IN
MAX88_C_A
MAX88_E_A
MAX88_MJA
V
= 11.5V, V
OUT
IN
OUT Leakage Current
I
3
µA
OUT LKG
= 2V, SET = OUT
10
_______________________________________________________________________________________
3
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
ELECTRICAL CHARACTERISTICS (continued)
(V = 6V (MAX883) or V = 4.3V (MAX882/MAX884), C
= 2.2µF, STBY or OFF = V , SET = GND, LBI = V , T = -40°C to
IN
IN
OUT
IN IN J
+85°C, unless otherwise noted. Typical values are at T = +25°C.) (Note 1)
J
PARAMETER
STBY Threshold Voltage
STBY Hysteresis
SYMBOL
CONDITIONS
STBY signal falling, MAX882_A
MAX882_A
MIN
TYP
1.20
7
MAX
UNITS
V
V
1.15
1.25
STBY
STBY
STBY
ΔV
mV
nA
STBY Input Leakage Current
I
V
= V or 0, MAX882_A
0.01
50
STBY
IN
V
In off mode, MAX883_A, MAX884_A
0.4
IL OFF
In on mode, SET = OUT, V < 6V,
IN
MAX883_A, MAX884_A
2.0
3.0
OFF Threshold Voltage
V
V
IH OFF
In on mode, SET = OUT, 6V < V < 11.5V,
IN
MAX883_A, MAX884_A
OFF Input Leakage Current
Output Noise
I
V
= V or 0
0.01
250
50
nA
OFF
OFF
IN
10Hz to 10kHz, SET = OUT, R = 1kΩ,
L
e
µV
RMS
n
C
= 2.2µF (Note 7)
OUT
Note 1:Electrical specifications are measured by pulse testing and are guaranteed for a junction temperature (T ) within the operat-
J
ing temperature range, unless otherwise noted. Specifications to -40°C are guaranteed by design and not production tested.
Note 2:(V - V
) is limited to keep the product (I
x (V - V
)) from exceeding the package power dissipation limits. See
IN
OUT
OUT
IN
OUT
Figure 5. Therefore, the combination of high output current and high supply voltage is not tested.
Note 3:Dropout Voltage is (V - V ) when V falls to 100mV below its nominal value at V = (V + 2V). For example, the
OUT
IN
OUT
OUT
IN
MAX883 is tested by measuring the V
at V = 7V, then V is lowered until V
falls 100mV below the measured value.
OUT
IN
IN
OUT
The difference (V - V
) is then measured and defined as ΔV
.
IN
OUT
DO
Note 4:Since standby mode inhibits the output but keeps all biasing circuitry alive, the Standby Quiescent Current is similar to the
normal operating quiescent current.
Note 5:Foldback Current Limit was characterized by pulse testing to remain below the maximum junction temperature (not
production tested).
Note 6:The Reverse-Current Protection Threshold is the output/input differential voltage (V
- V ) at which reverse-current
OUT
IN
protection switchover occurs and the pass transistor is turned off. See the section Reverse-Current Protection in the Detailed
Description.
Note 7:Noise is tested using a bandpass amplifier with two poles at 10Hz and two poles at 10kHz.
4
_______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Typical Operating Characteristics
(V = 7V for MAX883, VIN = 5.3V for MAX882/MAX884, OFF or STBY = VIN, SET = GND, LBI = V , LBO = OPEN, C = C
= 2.2µF,
IN
IN
IN
OUT
R = 1kΩ, T = +25°C, unless otherwise noted.)
L
A
OUTPUT VOLTAGE AND QUIESCENT
CURRENT vs. LOAD CURRENT
OUTPUT VOLTAGE
vs. TEMPERATURE
101
100
99
30
25
20
15
10
104
103
102
101
100
99
V
V
= 5V (MAX883)
OUT
OUT
= 3.3V (MAX882/MAX884)
98
97
96
95
I
Q
98
OUTPUT VOLTAGE
NORMALIZED TO OUTPUT
VOLTAGE AT 1mA
5
0
97
96
0.01
0.1
1
10
100 250
-55 -35 -15
5
25 45 65 85 105 125
LOAD CURRENT (mA)
TEMPERATURE (°C)
QUIESCENT CURRENT
vs. TEMPERATURE
OUTPUT VOLTAGE AND QUIESCENT
CURRENT vs. SUPPLY VOLTAGE
15
12
6
5
16
14
12
10
8
V
= 5V (MAX883)
OUT
4
3
2
1
V
= 3.3V (MAX882/MAX884)
9
6
3
0
OUT
I
(MAX882/MAX884)
Q
6
I
(MAX883)
Q
0
4
-55 -35 -15
5
25 45 65 85 105 125
2
3
4
5
6
7
8
9
10 11 12
TEMPERATURE (°C)
SUPPLY VOLTAGE (V)
DROPOUT VOLTAGE
vs. LOAD CURRENT
10Hz to 10kHz OUTPUT NOISE
0.6
0.5
0.4
0.3
0.2
0.1
0
V
= 3.3V (MAX882/MAX884)
OUT
V
= 5V (MAX883)
OUT
MAX883
= 5V
V
OUT
0
50
100
150 200
250 300
10ms/div
LOAD CURRENT (mA)
_______________________________________________________________________________________
5
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Typical Operating Characteristics (continued)
(V = 7V for MAX883, V = 5.3V for MAX882/MAX884, OFF or STBY = V , SET = GND, LBI = V , LBO = OPEN, C = C = 2.2µF,
OUT
IN
IN
IN
IN
IN
R = 1kΩ, T = +25°C, unless otherwise noted.)
L
A
LINE-TRANSIENT RESPONSE
LOAD-TRANSIENT RESPONSE
A
A
B
B
500μs/div
1ms/div
MAX883: V
= 5V, C = 0μF, t = 15μs, t = 13μs
IN R F
MAX883: V
= 5V, t = 24μs, t = 44μs
R F
OUT
OUT
A: V = 8V (HIGH) / V = 7V (LOW)
A: OUTPUT VOLTAGE (100mV/div)
B: I = 250mA (HIGH) / I = 50mA (LOW)
IN
IN
B: OUTPUT VOLTAGE (100mV/div)
OUT
OUT
LBO LOW VOLTAGE
vs. SINK CURRENT
OVERSHOOT AND TIME
EXITING SHUTDOWN MODE
5
4
3
2
1
0
R
= 100Ω
L
5V
B
A
MAX882/MAX884
MAX883
0V
500μs/div
0.1
1
10
50
A: OFF PIN VOLTAGE (1V/div):
RISE TIME = 9μs
SINK CURRENT (mA)
B: MAX883 OUTPUT VOLTAGE (1V/div):
DELAY = 135μs, RISE TIME = 67μs,
OVERSHOOT = 0%
6
_______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Pin Description
PIN
MAX883/
NAME
DESCRIPTION
MAX882
MAX884
Low-Battery Output is an open-drain output that goes low when LBI is less than 1.2V. Connect
to IN or OUT through a pull-up resistor. LBO is undefined during shutdown mode
(MAX883/MAX884).
1
2
1
LBO
SET
Feedback for setting the output voltage. Connect to GND to set the output voltage to the
preselected 3.3V or 5V. Connect to an external resistor network for adjustable-output operation.
2
Ground pins—also function as heatsinks in the SO package. All GND pins must be soldered to
the PC board for proper power dissipation. Connect to large copper pads or planes to channel
heat from the IC.
3, 6
3, 6
GND
Regulator Output. Fixed or adjustable from 1.25V to 11.0V. Sources up to 200mA. Bypass with a
2.2µF capacitor.
4
5
7
4
5
OUT
IN
Regulator Input. Supply voltage can range from 2.7V to 11.5V.
Standby. Active-low comparator input. Connect to GND to disable the output or to IN for normal
operation. A resistor network (from IN) can be used to set a standby mode threshold.
—
STBY
Shutdown. Active-low logic input. In OFF mode, supply current is reduced below 1µA and
—
8
7
8
OFF
LBI
V
= 0.
OUT
Low-Battery comparator Input. Tie to IN when not used.
3.3V for the MAX882/MAX884. Additional blocks
include a foldback current limiter, reverse-current pro-
tection, a thermal sensor, shutdown or standby logic,
and a low-battery-detection comparator.
_______________Detailed Description
The MAX882/MAX883/MAX884 are micropower, low-
dropout linear regulators designed primarily for battery-
powered applications. They feature Dual Mode operation,
allowing a fixed output of 5V for the MAX883 and 3.3V for
the MAX882/MAX884, or an adjustable output from 1.25V
to 11V. These devices supply up to 200mA while requiring
less than 15µA quiescent current. As illustrated in Figure
1, they consist of a 1.20V reference, error amplifier, MOS-
FET driver, P-channel pass transistor, dual-mode com-
parator, and feedback voltage-divider.
Internal P-Channel Pass Transistor
The MAX882/MAX883/MAX884 feature a 200mA P-
channel MOSFET pass transistor. This provides several
advantages over similar designs using PNP pass tran-
sistors, including longer battery life.
The P-channel MOSFET requires no base drive, which
reduces quiescent current considerably. PNP-based reg-
ulators waste large amounts of current in dropout when
the pass transistor saturates. They also use high base-
drive currents under large loads. The MAX882/MAX883/
MAX884 do not suffer from these problems and consume
only 11µA of quiescent current during light loads, heavy
loads, and dropout.
The 1.20V reference is connected to the error amplifier’s
inverting input. The error amplifier compares this refer-
ence with the selected feedback voltage and amplifies
the difference. The MOSFET driver reads the error signal
and applies the appropriate drive to the P-channel pass
transistor. If the feedback voltage is lower than the refer-
ence, the pass transistor’s gate is pulled lower, allowing
more current to pass and increasing the output voltage. If
the feedback voltage is too high, the pass transistor gate
is pulled up, allowing less current to pass to the output.
Output Voltage Selection
The MAX882/MAX883/MAX884 feature Dual Mode
operation. In preset voltage mode, the MAX883’s out-
put is set to 5V and the MAX882/MAX884’s output is set
to 3.3V, using internal trimmed feedback resistors.
Select this mode by connecting SET to ground.
The output voltage is fed back through either an inter-
nal resistor voltage-divider connected to the OUT pin,
or an external resistor network connected to the SET
pin. The dual-mode comparator examines the SET pin
voltage and selects the feedback path used. If the SET
pin is below 65mV, internal feedback is used and the
output voltage is regulated to 5V for the MAX883 or
In preset voltage mode, impedances between SET and
ground should be less than 100kΩ. Otherwise, spurious
conditions could cause the voltage at SET to exceed
the 65mV dual-mode threshold.
_______________________________________________________________________________________
7
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
IN
LBI
LOW-BATTERY
COMPARATOR
REVERSE-
CURRENT
PROTECTION
LBO
MOSFET DRIVER
WITH FOLDBACK
CURRENT LIMIT
P
N
ERROR AMP
SHUT-
DOWN
LOGIC
OFF
(STBY)
OUT
SET
1.20V
REFERENCE
DUAL-MODE
COMPARATOR
R1
R2
THERMAL
SENSOR
65mV
GND
( ) ARE FOR MAX882.
Figure 1. MAX882/MAX883/MAX884 Functional Diagram
In adjustable mode, the user selects an output voltage
in the 1.25V to 11V range by connecting two external
resistors, used as a voltage-divider, to the SET pin
(Figure 2).
Standby Mode (MAX882)
The MAX882 has a standby feature that disconnects
the input from the output when STBY is brought low, but
keeps all other circuitry awake. In this mode, V
OUT
drops to 0, and the internal biasing circuitry (including
the low-battery comparator) remains on. The maximum
quiescent current during standby is 15µA. STBY is a
comparator input with the other input internally tied to
the reference voltage. Use a resistor network as shown
in Figure 3 to set a standby-mode threshold voltage for
undervoltage lockout. Connect STBY to IN for normal
operation.
The output voltage is set by the following equation:
⎛
⎞
⎟
R1
R2⎠
V
= V
1 +
⎜
⎝
OUT
SET
where V
= 1.20V.
SET
To simplify resistor selection:
⎛
⎞
V
V
OUT
R1 = R2
− 1
⎟
⎜
⎝
⎠
SET
OFF Mode (MAX883/MAX884)
A low-logic input on the OFF pin shuts down the
MAX883/MAX884. In this mode, the pass transistor,
control circuit, reference, and all biases are turned off,
and the supply current is reduced to less than 1µA.
LBO is undefined in OFF mode. Connect OFF to IN for
normal operation.
Since the input bias current at SET is nominally zero,
large resistance values can be used for R1 and R2 to
minimize power consumption without losing accuracy.
Up to 1.5MΩ is acceptable for R2. Since the V
toler-
SET
ance is less than 40mV, the output can be set using
fixed resistors instead of trim pots.
8
_______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
INPUT
VOLTAGE
OUTPUT
VOLTAGE
IN
OUT
SET
IN
LBI
OUT
OUTPUT
VOLTAGE
INPUT
VOLTAGE
LBI
R1
R2
R1
R2
MAX882
MAX882
MAX883
MAX884
LOAD
OFF
(STBY)
STBY
C
C
OUT
IN
C
IN
C
2.2μF
OUT
2.2μF
O.1μF
GND
GND
SET
O.1μF
( ) ARE FOR MAX882.
R1 + R2
R1+ R2
V
= V
STBY
, V
STBY
= 1.20V
STBY TRIP
R2
V
OUT
= V
, V = 1.20V
SET
SET
R2
Figure 2. Adjustable Output Using External Feedback
Resistors
Figure 3. Setting an Undervoltage Lockout Threshold Using
STBY
Foldback Current Limiting
The MAX882/MAX883/MAX884 also include a foldback
current limiter. It monitors and controls the pass transis-
tor’s gate voltage, estimating the output current and
limiting it to 430mA for output voltages above 0.8V and
Power Dissipation and Operating Region
Maximum power dissipation of the MAX882/MAX883/
MAX884 depends on the thermal resistance of the case
and PC board, the temperature difference between the
die junction and ambient air, and the rate of
air flow. The power dissipation across the device is
(V - V
) > 0.7V. If the output voltage drops below
OUT
IN
0.8V, implying a short-circuit condition, the output cur-
rent is limited to 170mA. The output can be shorted to
ground for 1min without damaging the device if the
P = I
(V - V
). The resulting power dissipation
OUT
OUT IN
is as follows:
(T − T )
J
A
P =
package can dissipate (V x 170mA) without exceed-
IN
(θ + θ
)
JB
BA
ing T = +150°C. When the output is greater than 0.8V
J
and (V - V
) < 0.7V (dropout operation), no current
IN
OUT
where (T - T ) is the temperature difference between
J
A
limiting is allowed, to provide maximum load drive.
the MAX882/MAX883/MAX884 die junction and the sur-
rounding air, θ (or θ ) is the thermal resistance of
JB
JC
Thermal Overload Protection
Thermal overload protection limits total power dissipa-
tion in the MAX882/MAX883/MAX884. When the junc-
the package chosen, and θ is the thermal resistance
BA
through the PC board, copper traces, and other materi-
als to the surrounding air.
tion temperature exceeds T = +160°C, the thermal
J
The 8-pin small-outline package for the MAX882/
MAX883/MAX884 features a special lead frame with a
lower thermal resistance and higher allowable power
dissipation. This package’s thermal resistance package
is θ = 53°C/W, compared with θ = 110°C/W for an
sensor sends a signal to the shutdown logic, turning off
the pass transistor and allowing the IC to cool. The
thermal sensor turns the pass transistor on again after
the IC’s junction temperature cools by 10°C, resulting in
a pulsed output during thermal overload conditions.
JB
JB
8-pin plastic DIP package and θ = 125°C/W for an 8-
JB
Thermal overload protection is designed to protect the
MAX882/MAX883/MAX884 if fault conditions occur. It is
not intended to be used as an operating mode.
Prolonged operation in thermal-shutdown mode may
reduce the IC’s reliability. For continual operation, do
not exceed the absolute maximum junction temperature
pin ceramic DIP package.
rating of T = +150°C.
J
_______________________________________________________________________________________
9
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
1.6
MAX883, V
= 5V
OUT
250
200
MAXIMUM POWER
DISSIPATION LIMIT
8-PIN SO PACKAGE
1.5
1.4
1.3
1.2
1.1
1.0
0.9
77.4cm2,
MAXIMUM CURRENT
PLASTIC DIP
SINGLE-SIDED BOARD
1oz COPPER
GLASS EPOXY,
HIGH-
POWER
SOIC
T = +125°C,
J
150
100
50
T
A
= +25°C, STILL AIR
CERAMIC DIP
OPERATING
REGION AT
= +25°C
T
J
A
T = +125°C
0.1cm2
1cm2
10cm2
1.55in2
100cm2
15.5in2
0
0.0155in2
0.155in2
2
3
4
5
6
7
8
9
10 11 12 13
SUPPLY VOLTAGE (V)
COPPER GROUND PAD AREA
Figure 4. Typical Maximum Power Dissipation vs. Ground Pad
Area
Figure 5a. Safe Operating Regions: MAX882/MAX884 Maximum
Output Current vs. Supply Voltage
The GND pins of the MAX882/MAX883/MAX884 SOIC
package perform the dual function of providing an elect-
rical connection to ground and channeling heat away. Con-
nect all GND pins to ground using a large pad or ground
plane. Where this is impossible, place a copper plane on an
adjacent layer. For a given power dissipation, the pad
should exceed the associated dimensions in Figure 4.
250
MAXIMUM POWER
DISSIPATION LIMIT
MAXIMUM CURRENT
200
HIGH-
POWER
SOIC
Figure 4 assumes the IC is in an 8-pin small-outline pack-
age that has a maximum junction temperature of +125°C
and is soldered directly to the pad; it also has a +25°C
ambient air temperature and no other heat sources. Use
larger pad sizes for other packages, lower junction tem-
peratures, higher ambient temperatures, or conditions
where the IC is not soldered directly to the heat-sinking
ground pad. When operating C- and E-grade parts up to a
150
PLASTIC DIP
100
CERAMIC DIP
OPERATING
50
REGION AT
T
= +25°C
A
J
T = +125°C
0
T of +125°C, expect performance similar to M-grade
J
4
5
6
7
8
9
10 11 12 13
specifications. For T between +125°C and +150°C, the
J
SUPPLY VOLTAGE (V)
output voltage may drift more.
The MAX882/MAX883/MAX884 can regulate currents up
to 250mA and operate with input voltages up to 11.5V, but
not simultaneously. High output currents can only be sus-
tained when input-output differential voltages are small, as
shown in Figure 5. Maximum power dissipation depends
on packaging, temperature, and air flow. The maximum
output current is as follows:
Figure 5b. Safe Operating Regions: MAX883 Maximum Output
Current vs. Supply Voltage
P(T − T )
J
A
I
=
OUT(MAX)
(V − V
)100°C
IN
OUT
where P is derived from Figure 4.
10 ______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
OUTPUT
VOLTAGE
ON/OFF
OFF (STBY)
IN
OUT
LBO
IN
OUTPUT
VOLTAGE
*
BATTERY
OFF (STBY)
OUT
INPUT
VOLTAGE
R3
R1
R2
LBI
MAX882
MAX883
MAX884
GND
MAX882
LBI
MAX883
MAX884
SET
POWER-
BATTERY
C
2.2μF
C
OUT
OUT
FAIL
C
IN
2.2μF
C
INDICATION
IN
SET
GND
O.1μF
O.1μF
( ) ARE FOR MAX882.
( ) ARE FOR MAX882.
R1 + R2
V
= V
, V = 1.20V
LBI
LBI TRIP
LBI
R2
* OPTIONAL REVERSE BATTERY PROTECTION
Figure 6. Using the Low-Battery Comparator to Monitor Battery
Voltage
Figure 7. Typical 3.3V or 5V Linear Regulator Circuit
Reverse-Current Protection
The MAX882/MAX883/MAX884 have a unique protection
scheme that limits reverse currents when the input volt-
age falls below the output. It monitors the voltages on IN
and OUT and switches the IC’s substrate and power bus
to the more positive of the two. The control circuitry is
then able to remain functioning and turn the pass transis-
tor off, limiting reverse currents back through to the input
of the device. In this mode, typical current into OUT to
Applications Information
The MAX882/MAX883/MAX884 are series linear regula-
tors designed primarily for battery-powered systems.
Figure 7 shows a typical application.
Standby Mode vs. OFF Mode
STBY is a comparator input that allows the user to set
the standby-mode threshold voltage, while OFF is a
logic-level input. When in standby mode, the output is
disconnected from the input, but the biasing circuitry
(including the low-battery comparator) is kept alive,
causing the device to draw approximately 7µA.
Standby mode is useful in applications where a low-
battery comparator function is still needed in shutdown.
GND is 15µA at V
= 3.3V and 50µA at V
= 5V.
OUT
OUT
Reverse-current protection activates when the voltage
on IN falls 6mV (or 20mV max) below the voltage on
OUT. Before this happens, currents as high as several
milliamperes can flow back through the device.
A logic low at the OFF pin turns off all biasing circuitry,
including the LBI/LBO comparator, and reduces supply
current to less than 1µA. OFF mode is useful for maxi-
mizing battery life. There is little difference in the time it
takes to exit standby mode or OFF mode.
Low-Battery-Detection Comparator
The MAX882/MAX883/MAX884 provide a low-battery com-
parator that compares the voltage on the LBI pin to the
1.20V internal reference. LBO, an open-drain output, goes
low when LBI is below 1.20V. Hysteresis of 7mV has been
added to the low-battery comparator to provide noise
immunity during switching. LBO remains functional in stand-
by mode for the MAX882, but is undefined in OFF mode for
the MAX883 and MAX884. Tie LBI to IN when not used.
Output Capacitor Selection
and Regulator Stability
An output filter capacitor is required at the MAX882/
MAX883/MAX884 OUT pin. The minimum output
capacitance required for stability is 2.2µF.
Use a resistor-divider network as shown in Figure 6 to set
the low-battery trip voltage. Current into the LBI input is
50nA (max), so R2 can be as large as 1MΩ. Add extra
noise immunity by connecting a small capacitor from LBI
to GND. Additional hysteresis can be added by connect-
ing a high-value resistor from LBI to LBO.
______________________________________________________________________________________ 11
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
80
70
60
50
40
A: C
B: C
C: C
= 1μF
= 10μF
= 100μF
OUT
OUT
OUT
60
50
I
= 1mA
OUT
40
30
30
C
20
10
0
MAX884
B
MAX883
20
10
0
A
ΔV = 1V
IN
IN
OUT
P-P
ΔV = 1V
IN
IN
OUT
P-P
C
C
= 0μF
C
= 0μF
= 2.2μF
I
= 100mA
I
= 100mA
105
OUT
100 101
102
103
104
106
101
102
103
104
105
106
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 8a. Power-Supply Rejection Ratio vs. Ripple Frequency
for Light and Heavy Loads
Figure 8b. Power-Supply Rejection Ratio vs. Ripple Frequency
for Various Output Capacitances
The filter capacitor’s size depends primarily on the
desired power-up time and load-transient responses.
Load-transient response is improved by using larger
output capacitors.
Noise
The MAX882/MAX883/MAX884 exhibit up to 4mV
of
p-p
noise during normal operation. This is negligible in
most applications. When using the MAX882/MAX883/
MAX884 for applications that include analog-to-digital
converters (ADCs) with resolutions greater than 12 bits,
consider the ADC’s power-supply rejection specifica-
tions. See the output noise plot in the Typical Operating
Characteristics section.
The output capacitor’s equivalent series resistance
(ESR) will not affect stability as long as the minimum
capacitance requirement is observed. The type of
capacitor selected is not critical, but it must remain
above the minimum value over the full operating temper-
ature range.
PSRR and Operation from
Sources Other than Batteries
Input Bypass Capacitor
Normally, use 0.1µF to 10µF capacitors on the MAX882/
MAX883/MAX884 input. The best value depends pri-
The MAX882/MAX883/MAX884 are designed to
achieve low dropout voltages and low quiescent cur-
rents in battery-powered systems. However, to gain
these benefits, the devices must trade away power-
supply noise rejection, as well as swift response to sup-
ply variations and load transients. For a 1mA load
current, power-supply rejection ranges from 60dB
down to 20dB at 2kHz. At higher frequencies, the cir-
cuit depends primarily on the characteristics of the out-
put capacitor, and the PSRR increases (Figure 8).
marily on the power-up slew rate of V , and on load
IN
and line transients. Larger input capacitor values pro-
vide better supply-noise rejection and line-transient
response, as well as improved performance, when the
supply has a high AC impedance. The type of input
bypass capacitor used is not critical.
12 ______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Input-Output (Dropout) Voltage
A regulator’s minimum input-output voltage differential
(or dropout voltage) determines the lowest usable sup-
INPUT
VOLTAGE
ply voltage. In battery-powered systems, this deter-
OUTPUT
VOLTAGE
mines the useful end-of-life battery voltage. Because
the MAX882/MAX883/MAX884 use a P-channel MOS-
FET pass transistor, their dropout voltage is a function
IN
OUT
LBI
C
OUT
of R
multiplied by the load current (see Electrical
DS(ON)
2.2μF
R1
R2
MAX882
D2
Characteristics). Quickly stepping up the input voltage
from the dropout voltage can result in overshoot.
STBY
Short-Term Battery Backup
Using the MAX882
C
IN
O.1μF
BACKUP
BATTERY
GND
SET
Figure 9 illustrates a scheme for implementing battery
backup for 3.3V circuits using the MAX882. When the
supply voltage drops below some user-specified value
based on resistors R1 and R2, the standby function
activates, turning off the MAX882’s output. Under
these conditions, the backup battery supplies power to
the load. Reverse current protection prevents the bat-
tery from draining back through the regulator to the
input.
Figure 9. Short-Term Battery Backup Using the MAX882
When operating from sources other than batteries, sup-
ply-noise rejection and transient response can be
improved by increasing the values of the input and out-
put capacitors and employing passive filtering tech-
niques. Do not use power supplies with ripple voltage
exceeding 200mV at 100kHz.
This application is limited to short-term battery backup
for 3.3V circuits. The current drawn by the MAX882’s
OUT pin at 3.3V during reverse-current protection is
typically 8µA. It should not be used with the MAX883
and MAX884, since the OFF pin is a logic input, and
indeterminate inputs can cause the regulator to turn on
intermittently, draining the battery.
Overshoot and Transient Considerations
The Typical Operating Characteristics section shows
power-up, supply, and load-transient response graphs.
On the load-transient graphs, two components of the
output response can be observed: a DC shift from the
output impedance due to the different load currents,
and the transient response. Typical transients for step
changes in the load current from 50mA to 250mA are
200mV. Increasing the output capacitor’s value attenu-
ates transient spikes.
Reverse Battery Protection
Reverse battery protection can be added by including
an inexpensive Schottky diode between the battery
input and the regulator circuit, as shown in Figure 7.
However, the dropout voltage of the regulator will be
increased by the forward voltage drop of the diode. For
example, the forward voltage of a standard 1N5817
Schottky diode is typically 0.29V at 200mA.
During recovery from shutdown, overshoot is negligible
if the output voltage has been given time to decay ade-
quately. During power-up from V = 0, overshoot is
IN
typically less than 1% of V
.
OUT
______________________________________________________________________________________ 13
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Ordering Information (continued)
___________________Chip Topography
PIN-
PACKAGE
PART
TEMP RANGE
LB0
GND
MAX883CPA
MAX883CSA
MAX883C/D
MAX883EPA
MAX883ESA
MAX883MSA/PR
0°C to +70°C
0°C to +70°C
8 PDIP
8 SO
LBI
0°C to +70°C
Dice*
8 PDIP
8 SO
SET
OUT
OFF (MAX883/4)
STBY (MAX882)
-40°C to +85°C
-40°C to +85°C
-55°C to +125°C
8 SO**
8 SO**
8 PDIP
8 SO
0.085"
(2.159mm)
MAX883MSA/PR-T -55°C to +125°C
MAX884CPA
MAX884CSA
MAX884C/D
MAX884EPA
MAX884ESA
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
Dice*
8 PDIP
8 SO
IN
OUT
*Dice are tested at T = +25°C, DC parameters only.
**Contact factory for availability.
J
0.080"
(2.032mm)
NO DIRECT SUBSTRATE CONNECTION. THE N-SUB-
STRATE IS INTERNALLY SWITCHED BETWEEN THE
MORE POSITIVE OF IN OR OUT.
14 ______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Package Information
(For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.)
PACKAGE TYPE
8 PDIP
PACKAGE CODE
P8-T
DOCUMENT NO.
21-0043
8 SO
S8-6F
21-0041
______________________________________________________________________________________ 15
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Package Information (continued)
(For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.)
INCHES
MILLIMETERS
DIM
A
MIN
MAX
0.069
0.010
0.019
0.010
MIN
1.35
0.10
0.35
0.19
MAX
1.75
0.25
0.49
0.25
0.053
0.004
0.014
0.007
N
A1
B
C
e
0.050 BSC
1.27 BSC
E
0.150
0.228
0.016
0.157
0.244
0.050
3.80
5.80
0.40
4.00
6.20
1.27
E
H
H
L
VARIATIONS:
INCHES
1
MILLIMETERS
DIM
D
MIN
MAX
0.197
0.344
0.394
MIN
4.80
8.55
9.80
MAX
5.00
N
8
MS012
AA
TOP VIEW
0.189
0.337
0.386
D
8.75 14
10.00 16
AB
D
AC
D
C
A
B
0∞-8∞
e
A1
L
FRONT VIEW
SIDE VIEW
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, .150" SOIC
APPROVAL
DOCUMENT CONTROL NO.
REV.
1
21-0041
B
1
16 ______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout,
Low I , 200mA Linear Regulators
Q
Revision History
REVISION
NUMBER
REVISION
DATE
PAGES
DESCRIPTION
CHANGED
3
9/08
Added information for rugged plastic product
14
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 17
© 2008 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
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