SPX2954AS-L-5-0 [EXAR]

Regulator, 1 Output, BIPolar, PDSO8,;
SPX2954AS-L-5-0
型号: SPX2954AS-L-5-0
厂家: EXAR CORPORATION    EXAR CORPORATION
描述:

Regulator, 1 Output, BIPolar, PDSO8,

光电二极管
文件: 总15页 (文件大小:577K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
SPX2954  
250mA Low Dropout Voltage Regulator  
Description  
FEATURES  
The SPX2954 and SPX2954A are low power voltage regulators.  
These devices are an excellent choice for use in battery-powered  
applications such as cordless telephones, radio control systems,  
and portable computers. The SPX2954 and SPX2954A feature low  
quiescent current and low dropout voltage (typ. 20mV at 100µA and  
310mV at 250mA). This includes a tight initial tolerance (0.5% for  
SPX2954A), extremely good load and line regulation (0.05% typ.),  
and very low output temperature coefficient (20 ppm/°C typ.), making  
the SPX2954/SPX2954A useful as a low-power voltage reference.  
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5.0V and 3.3V versions at 250mA output  
Accurate 0.5% for SPX2954A  
Very low quiescent current  
Low dropout: 310mV at 250mA  
Extremely tight load and line regulation  
Very low temperature coefficient  
Current and thermal limiting  
Need only 1µF for stability  
Direct replacement for LP2954  
Error flag warns of output dropout  
Logic-controlled electronic shutdown  
Programmable output from 1.24V to 30V  
The error flag output feature is used as a power-on reset for warning  
of a low output voltage, due to a falling input voltage. The logic-  
compatible shutdown feature enables the regulator to be switched  
ON and OFF. The SPX2954/SPX2954A is offered in a 3-pin SOT-223  
package and an 8-pin SOIC package.  
Typical Application  
VIN  
100K  
8
VIN  
ERROR  
5
1.2 to 30V  
ERROR  
1
OUTPUT  
VOUT  
SPX2954  
+
SHUTDOWN  
INPUT  
3
R1  
3.3μF  
SD  
.01μF  
FB  
GND  
7
4
1.23V  
VREF  
R2  
Typical Application  
REV1A  
1/15  
SPX2954  
Absolute Maximum Ratings  
Stresses beyond the limits listed below may cause  
permanent damage to the device. Exposure to any Absolute  
Maximum Rating condition for extended periods may affect  
device reliability and lifetime.  
Feedback Input Voltage................................... -1.5V to 30V  
Shutdown Input Voltage .................................. -0.3V to 30V  
Error Comparator Voltage ............................... -0.3V to 30V  
ESD Rating............................................................. 2kV Min  
Power Dissipation..................................... Internally Limited  
Lead Temperature (soldering, 5 seconds)................. 260°C  
Storage Temperature .................................. -65°C to 150°C  
Operating Junction Temperature Range ..... -40°C to 125°C  
Input Supply Voltage ....................................... -0.3V to 30V  
REV1A  
2/15  
SPX2954  
Electrical Characteristics  
Unless otherwise noted: V = V + 1V, I = 100µA, C = 1µF(2) T = 25°C.  
IN  
O
L
L
A
SPX2954A  
Typ  
SPX2954  
Typ  
Parameter  
Conditions  
Units  
Max  
Min  
Max  
Min  
3.3V Versions  
T = 25°C  
3.284  
3.267  
3.260  
3.251  
3.3  
3.3  
3.3  
3.3  
3.317  
3.333  
3.340  
3.350  
3.267  
3.251  
3.234  
3.201  
3.3  
3.3  
3.3  
3.3  
3.333  
J
Output Voltage  
-25°C ≤ T ≤ 85°C  
3.350  
3.366  
3.399  
V
V
J
Full Operating Temp.  
Output Voltage  
5V Versions  
100µA ≤ I ≤ 250mA; T ≤ T  
L J MAX  
T = 25°C  
4.975  
4.950  
4.940  
4.925  
5.0  
5.0  
5.0  
5.0  
5.025  
5.050  
5.060  
5.075  
4.950  
4.925  
4.900  
4.850  
5.0  
5.0  
5.0  
5.0  
5.050  
5.075  
5.100  
5.150  
J
Output Voltage  
-25°C ≤ T ≤ 85°C  
V
V
J
Full Operating Temp.  
Output Voltage  
100µA ≤ I ≤ 250mA; T ≤ T  
L J MAX  
All Voltage Options  
Output Voltage Temperature  
Coefficient(1)  
20  
100  
50  
150  
ppm/°C  
Line Regulation(3)  
Load Regulation(3)  
V
+ 1V ≤ V ≤ 30V; I(4)  
0.03  
0.04  
60  
0.10  
0.20  
100  
450  
500  
170  
6
0.04  
0.10  
60  
0.20  
0.30  
100  
450  
500  
170  
6
%
%
O
IN  
100µA ≤ I ≤ 250mA  
L
I = 1mA  
L
Dropout Voltage(5)  
I = 100mA  
L
290  
310  
150  
3
290  
310  
150  
3
mV  
I = 250mA  
L
I = 1mA  
L
µA  
Ground Current  
Current Limit  
I = 100mA  
L
mA  
I = 250mA  
L
10  
14  
10  
14  
V
OUT  
= 0  
270  
0.05  
430  
160  
550  
0.2  
270  
0.05  
430  
160  
550  
0.2  
mA  
%/W  
C = 1µF  
µV  
L
rms  
rms  
Thermal Regulation Output Noise,  
10Hz to 100kHz  
C = 200µF  
µV  
L
C = 3.3µF, Bypass = 0.01µF from pin 7  
to Pin 1 (8 pin versions)  
L
100  
100  
µV  
rms  
8-Pin Version Only  
Reference Voltage  
1.220 1.235 1.250  
1.210  
1.185  
1.235  
1.260  
1.285  
60  
V
Over Temp(6)  
1.190  
2.270  
60  
V
nA  
Feedback Pin Bias Current  
Vref Temperature Coefficient  
40  
20  
40  
50  
ppm/°C  
Feedback I  
Coefficient  
Temperature  
BIAS  
0.1  
0.1  
nA/°C  
REV1A  
3/15  
SPX2954  
SPX2954A  
Typ  
SPX2954  
Typ  
Parameter  
Conditions  
Units  
Max  
Min  
40  
Max  
Min  
40  
Error Comparator  
Output Leakage Current  
Output Low Voltage  
Upper Threshold Voltage(7)  
Lower Threshold Voltage(7)  
Hystersis(7)  
V
V
= 30V  
0.01  
150  
60  
1
0.01  
150  
60  
1
µA  
mA  
mA  
mV  
mV  
OH  
= V - 0.5V; I = 400µA  
250  
250  
IN  
O
OL  
75  
95  
75  
95  
15  
15  
Shutdown  
Low (Regulator ON)  
High (Regulator OFF)  
1.3  
0.7  
1.3  
0.7  
Input Logic Voltage  
V
2.0  
2.0  
V
V
= 2.4V  
= 30V  
30  
50  
30  
50  
S
S
Shutdown Input Current  
µA  
µA  
400  
800  
400  
800  
Regulator Output Current in  
Shutdown(8)  
3
10  
3
10  
Thermal Resistance Ѳ  
JA  
SOIC-8  
128.4  
62.3  
°C/W  
°C/W  
SOT-223  
NOTES:  
1. Output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range.  
2. Unless otherwise specified all limits guaranteed for TJ = 25°C, VIN = 6V, IL = 100µA and CL = 1µF. Additional conditions for the 8-pin versions are feedback tied to 5V tap  
and output tied to output sense (VOUT = 5V) and VSHUTDOWN ≤ 0.8V.  
3. 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 under the  
specification for thermal regulation.  
4. Line regulation for the SPX2954 is tested at IL = 1mA.  
5. Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV 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.  
6. VREF ≤ VOUT ≤ (VIN - 1V), 2.3 ≤ VIN ≤ 30V, 100µA ≤ IL ≤ 250mA, TJ ≤ TJMAX  
.
7. 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 95mV x 5V/1.235 = 384mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the  
dropout warning occurring at typically 5% below nominal, 7.5% guaranteed.  
8. VSHUTDOWN ≥ 2V, VIN ≤ 30V, VOUT = 0, Feedback pin tied to 5V/3.3V Tap.  
Pin Configurations  
INPUT  
OUTPUT  
SENSE  
1
2
3
4
8
7
6
5
SPX2954  
FEEDBACK  
5V, 3.3V TA P  
ERROR  
SPX2954  
1
2
3
SHUTDOWN  
GND  
GND  
V
V
IN  
OUT  
Front View  
Top View  
SOT-223 Package (M3)  
8-Pin Surface Mount (S)  
REV1A  
4/15  
SPX2954  
Functional Block Diagram  
UNREGULATED DC  
5V  
1
7
8
+
INPUT  
FEEDBACK  
OUTPUT  
2
SENSE  
+
_
180kΩ  
60kΩ  
6
ERROR  
AMPLIFIER  
3
330kΩ  
5V TAP  
FROM  
CMOS OR  
TTL  
SHUTDOWN  
+
60 mV  
1μ F  
.
5
+
+
_
ERROR  
.
ERROR DETECTION  
COMPARATOR  
TO  
1.23V  
+
CMOS OR  
TTL  
4
REFERENCE  
GROUND  
SPX2954 Block Diagram, 8-Lead 5V Version  
Typical Performance Characteristics  
1.8  
1.6  
5
4
3.5  
3.0  
IL = 100mA  
CL = 1µF  
2.5  
2.0  
1.5  
1.0  
2
1.4  
1.2  
CL = 220µF  
0
C
L = 3.3µF  
CBYP = 0.1µF  
-2  
1
~
~
~
1.0  
0.8  
1.25W  
0.5  
0.0  
0
0.6  
-1  
-75 -50 -25  
0
25 50 75 100 125 150  
102  
103  
104  
105  
0
10  
20  
30  
40  
50  
TIME (µs)  
FREQUENCY (Hz), CBYP=0.1uF  
TEMPERATURE (˚C)  
Shutdown Threshold Voltage  
Thermal Response  
Output Noise  
30  
25  
20  
15  
80  
70  
60  
50  
40  
30  
20  
10  
IL = 50mA  
L = 100mA  
I
L = 100µA  
TJ = 150 ºC  
10  
5
I
IL = 1mA  
0
~
~
C
L = 1μF  
VIN = 6V  
OUT = 5V  
10  
5
V
TJ = 125 ºC  
IL = 100µA  
0
-5  
-10  
5
10  
15  
20  
25  
30  
101  
102  
103  
104  
105  
106  
INPUT VOLTAGE (V)  
FREQUENCY (Hz)  
Line Regulation  
Ripple Rejection  
REV1A  
5/15  
SPX2954  
Typical Performance Characteristics (Continued)  
10  
6
250  
225  
200  
5
4
RL=50kΩ  
175  
150  
1
RL=50kΩ  
3
2
125  
RL=50kΩ  
100  
75  
RL= ∞  
0.1  
50  
25  
0
1
0
0.01  
0
1
2
3
4
5
6
7
8
9
10  
0.1  
1
10  
100  
0
1
2
3
4
5
6
INPUT VOLTAGE (VOLTS)  
INPUT VOLTAGE (VOLTS)  
LOAD CURRENT (mA)  
Input Current  
Quiescent Current  
Dropout Characteristics  
6
5
320  
280  
160  
150  
140  
130  
120  
110  
100  
90  
RL=50kΩ  
OUT=5V  
240  
200  
160  
V
I L=1mA  
I L=0  
VIN=6V  
IL=100mA  
80  
70  
120  
80  
60  
50  
40  
30  
20  
10  
0
4
40  
3
0
0
1
2
3
4
5
6
7
8
-75  
-25  
0
25 50 75 100 125 150  
-50  
0
1
2
3
4
5
6
7
8
9
10  
INPUT VOLTAGE (VOLTS)  
TEMPERATURE (ºC)  
INPUT VOLTAGE (VOLTS)  
Ground Current  
Ground Current  
Input Current  
190  
170  
150  
8
7
6
I L=100mA  
5
4
VIN=6V  
I L=100μA  
3
2
1
130  
0
-75 -50 -25  
0
25 50 75 100 125 150  
0
1
2
3
4
5
6
7
8
TEMPERATURE (ºC)  
INPUT VOLTAGE  
Ground Current  
Quiescent Current  
REV1A  
6/15  
SPX2954  
Typical Performance Characteristics (Continued)  
500  
240  
230  
500  
I L = 150m A  
400  
300  
400  
300  
220  
210  
200  
190  
180  
200  
~
~
200  
40  
20  
0
T J = 25ºC  
100  
0
I L = 100μ A  
170  
100μA  
1mA  
OUTPUT CURRENT  
10mA  
-75 -50 -25  
0
25 50 75 100 125 150  
100mA  
-75 -50 -25  
0
25 50 75 100 125 150  
TEMPERATURE (ºC)  
TEMPERATURE (ºC)  
Drop-Out Voltage  
Drop-Out Voltage  
Short Circuit Current  
8
6
4
2.5  
100  
mV  
V
= 5V  
OUT  
T A = 125ºC  
50  
2.0  
mV  
0
1.5  
1.0  
T A = 25ºC  
T A = -55ºC  
C L = 1μ F  
HYSTERESIS  
-50  
mV  
I L = 1mA  
V OUT = 5V  
~
2
~
8V  
0
0.5  
0.0  
6V  
4V  
PULLUP RESISTOR TO  
SEPARATE 5V SUPPLY  
-2  
0
1
2
3
4
5
0
200  
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9  
OUTPUT LOW VOLTAGE (V)  
400  
TIME(μs)  
600  
800  
INPUT VOLTAGE (V)  
Error Comparator Output  
Comparator Sink Current  
Line Transient Response  
10  
90  
80  
70  
60  
50  
40  
90  
80  
70  
60  
50  
40  
30  
20  
I O = 100μ A  
I O = 1mA  
5
2
C L = 1μ F  
V IN = 6V  
I L = 1mA  
V OUT = 5V  
I L = 0  
I O = 100m A  
1
0.5  
0.2  
V OUT = 5V  
C L = 1μ F  
0.1  
0.05  
I L = 100μ A  
C L = 1μ F  
V IN = 6V  
30  
V OUT = 5V  
0.02  
0.01  
I L = 10m A  
20  
10  
100  
1K  
10K  
100K  
1M  
10 1  
10 2  
10 4  
FREQUENCY (Hz)  
10 5  
10 3  
10 6  
10 1  
10 2  
10 3 10 4  
FREQUENCY (Hz)  
10 5  
10 6  
FREQUENCY (Hz)  
Output Impedance  
Ripple Rejection  
Ripple Rejection  
REV1A  
7/15  
SPX2954  
Typical Performance Characteristics (Continued)  
20  
50  
0
2.3  
PIN 7 DRIVEN BY EXTERNAL  
SOURCE (REGULATOR RUN  
OPEN LOOP)  
10  
-50  
2.1  
0
TA=125ºC  
-100  
-150  
-200  
-250  
-10  
TA= 25ºC  
1.9  
TA= 55ºC  
-20  
-30  
-75 -50 -25  
1.7  
-75 -50 -25  
0
25 50 75 100 125 150  
-2.0  
-1.5 -1.0  
-0.5  
0
0.5  
1.0  
0
25 50 75 100 125 150  
TEMPEATURE (ºC)  
FEEDBACK VOLTA GE (V)  
TEMPERATURE (ºC)  
Minimum Operating Voltage  
Feedback Bias Current  
Feedback Pin Current  
250  
200  
150  
80  
60  
40  
7
CL=1μF  
6
5
4
100  
50  
20  
0
3
2
1
0
0
-20  
-40  
-60  
IL=10mA  
VIN=8V  
OUT=5V  
CL=10μF  
-50  
-100  
V
OUT=5V  
CL=1μF  
V
CL=10μF  
V
OUT=5V  
~
~
~
~
2
0
100mA  
100μA  
100μA  
100μA  
-2  
0
1
2
3
4
5
-100  
0
100 200 300 400 500 600 700  
TIME (us)  
0
4
8
12  
16  
20  
TIME (ms)  
Load Transient Response  
Load Transient Response  
Enable Transient  
120  
400  
120  
8-PIN MOLDED  
DIP SOLDERED  
TO PC BOARD  
TO-92 PACKAGE  
0.25” LEADS SOLDERED  
TO PC BOARD  
100  
80  
100  
80  
300  
200  
100  
TJMAX=125˚C  
TOUT=5V  
VOUT=5V  
TIMAX=125˚C  
60  
40  
60  
TA=25˚C  
40  
20  
0
TA=25˚C  
TA=50˚C  
TA=85˚C  
20  
0
TA=85˚C  
0
0
5
10  
15  
20  
25  
30  
0
5
10  
15  
20  
25  
30  
-75 -50 -25  
0
25 50 75 100 125 150  
INPUT VOLTAGE (V)  
TEMPERATURE (ºC)  
INPUT VOLTAGE (V)  
Maximum Rated Output  
Divider Resistance  
Maximum Rated Output Current  
REV1A  
8/15  
SPX2954  
Applications Information  
External Capacitors  
The error comparator has an open-collector output, which  
requires an external pull-up resistor. Depending on the  
system requirements the resistor may be returned to 5V  
output or other supply voltage. In determining the value of  
this resistor, note that the output is rated to sink 400mA,  
this value adds to battery drain in a low battery condition.  
Suggested values range from 100k to 1MΩ. If the output is  
unused this resistor is not required.  
The stability of the SPX2954 requires a 1µF or greater  
capacitor between output and ground. Oscillation could occur  
without this capacitor. Most types of tantalum or aluminum  
electrolytic works fine here. For operations below -25°C solid  
tantalum is recommended since the many aluminum types  
have electrolytes that freeze at about -30°C. The ESR of  
about 5Ω or less and resonant frequency above 500kHz are  
the most important parameters in the value of the capacitor.  
The capacitors value may be increased without limit.  
At lower values of output current, less output capacitance  
is required for stability. For the currents below 10mA the  
value of the capacitor can be reduced to 0.33µF and 0.1µF  
for 1mA. More output capacitance is needed for the 8-pin  
version at voltages below 5V since it runs the error amplifier  
at lower gain. At worst case 3.3µF or greater must be used  
for the condition of 150mA load at 1.23V output.  
4.75V  
OUTPUT  
VOLTAGE  
_______  
ERROR*  
The SPX2954 unlike other low dropout regulators will remain  
stable and in regulation with no load in addition to the  
internal voltage divider. This feature is especially important  
in applications like CMOS RAM keep-alive. When setting  
the output voltage of the SPX2954 version with external  
resistors, a minimum load of 1µA is recommended.  
+
5.0V  
+
INPUT  
VOLTAGE  
+
1.3V  
+
* See Application Info.  
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 then  
a 1µF tantalum or aluminum electrolytic capacitor should be  
placed from the input to the ground.  
Figure 1. Error Output Timing  
Instability can occur if there is stray capacitance to the  
SPX2954 feedback terminal (pin 7). This could cause more  
problems when using a higher value of external resistors  
to set the output voltage. This problem can be fixed by  
adding a 100pF capacitor between output and feedback and  
increasing the output capacitor to at least 3.3µF.  
Programming the Output Voltage of SPX2954  
The SPX2954 may be pin-strapped for 5V using its internal  
voltage divider by tying Pin 1 (output) to Pin 2 (sense) and Pin  
7 (feedback) to Pin 6 (5V Tap). Also, it may be programmed  
for any output voltage between its 1.235V reference and  
its 30V maximum rating using an external pair of resistors.  
Refer to the below equation for the programming of the  
output voltage:  
Error Detection Comparator Output  
V
= V  
x (1 + R /R ) + I  
R
OUT  
REF  
1
2
FB 1  
The comparator produces a logic low output whenever  
the SPX2954 output falls out of regulation by more than  
around 5%. This is around 60mV offset divided by the  
1.235 reference voltage. This trip level remains 5% below  
normal regardless of the programmed output voltage of the  
regulator.  
The V  
is 1.235 and I  
nominally -20nA. The minimum recommended load current  
of 1µA forces an upper limit of 1.2MΩ on value of R . If no  
is the feedback bias current,  
FB  
REF  
2
load is presented the I produces an error of typically 2%  
FB  
in V  
which may be eliminated at room temperature by  
Figure 1 shows the timing diagram depicting the ERROR  
signal and the regulator output voltage as the SPX2954  
input is ramped up and down. The ERROR signal becomes  
low at around 1.3V input, and goes high around 5V input  
OUT  
trimming R . To improve the accuracy choose the value of  
1
R2 = 100k this reduces the error by 0.17% and increases  
the resistor program current by 12µA. Since the SPX2954  
typically draws 60µA at no load with Pin 2 open-circuited,  
this is a small price to pay.  
(input voltage at which V  
= 4.75). Since the SPX2954’s  
OUT  
dropout voltage is load dependent, the input voltage trip  
point (around 5V) will vary with the load current. The output  
voltage trip point (approx. 4.75V) does not vary with load.  
REV1A  
9/15  
SPX2954  
Reducing Output Noise  
It may be an advantage to reduce the AC noise present at  
the output. One way is to reduce the regulator bandwidth by  
increasing the size of the output capacitor. This is the only  
way that noise can be reduced on the 3 lead SPX2954 but is  
relatively inefficient, as increasing the capacitor from 1µF to  
220µF only decreases the noise from 430µV to 160µVRMS  
for a 100kHz bandwidth at 5V output. Noise can be reduced  
+VIN  
8
+VIN  
______  
ERROR  
5
ERROR  
*VOUT =VIN  
1
OUTPUT  
VOUT  
fourfold by using a bypass capacitor across R , since it  
1
reduces the high frequency gain from 4 to unity. Pick  
SPX2954  
C
≈ (1 / 2πR x 200Hz)  
1
BYPASS  
3
SHUTDOWN  
INPUT  
SD  
FB  
GND  
7
4
or choose 0.01µF. When doing this, the output capacitor must  
be increased to 3.3µF to maintain stability. These changes  
reduce the output noise from 430µV to 100µVRMS for a  
100kHz 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.  
*MINIMUM INPUT-OUTPUT VOLTAGE RANGES FROM 40mV to 400mV.  
DEPENDING ON LOAD CURRENT.  
Figure 3. Wide Input Voltage Range, Current Limiter  
+V  
IN  
470KΩ  
8
+VIN  
_____  
ERROR  
5
V OUT  
1
470KΩ  
VOUT  
SPX2954  
+
3
R1  
1μF  
SD  
FB  
GND  
4
RESET  
7
R 2  
Figure 2. Latch Off when Error Flag Occurs  
REV1A  
10/15  
SPX2954  
Applications Information (continued)  
+
6V  
SEALED  
LEAD-ACID  
BATTERY  
SOURCE  
1.5kΩ  
120kΩ  
FB  
8
1N457  
VIN  
1
2
MAIN V+  
SPX385  
VOUT  
SPX2954  
MEMORY V+  
20kΩ  
400kΩ  
FOR 5.5 V  
+
3
1μF  
SD  
100kΩ  
GND  
4
NI-CAD  
BACKUP  
BATTERY  
Figure 4. Low Battery Disconnect  
Figure 5. Regulator with State of Charge Indicator  
REV1A  
11/15  
SPX2954  
Applications Information (continued)  
+VIN  
8
10KΩ  
5 DEGREE SHUTDOWN FLAG  
.
VIN  
5
1
3
AUX SHUTDOWN  
INPUT  
SD  
ERROR  
OFF  
SPX2954  
ON  
VOUT  
FB  
GND  
EXTERNAL CIRCUIT  
4
PROTECTED FROM  
OVER TEMPERATURE  
(V+ GOES OFF WHEN  
TEMP > 125)  
7
OR  
+
TEMP  
SENSOR  
AS35  
RELAY  
-
8.2KΩ  
Figure 6. System Over Temperature Protection  
+5V  
UNREGULATED INPUT  
4.7mA  
4
20m A  
8
8
OUTPUT  
330kΩ  
IN  
2N5432  
(2)  
1
VIN  
VOUT  
1
VOUT  
FB  
27kΩ  
1N4001  
SPX2954  
SPX2954  
7
5V  
6
2
0.1μ F  
2
SENSE  
V TA P  
OUTPUT  
FB  
GND  
+
GND  
4
4
4.7μ F  
7
LOAD  
50mA  
to  
360KΩ  
1N457  
300mA  
MIN VOLTAGE = 4V  
Figure 7. Open Circuit Detector for 4mA to 20mA Current  
Loop  
Figure 8. 300mA Regulator with 0.75V  
REV1A  
12/15  
SPX2954  
Package Description  
SOT-223-3  
FRONT VIEW  
TOP VIEW  
BOTTOM VIEW  
TERMINAL DETAILS  
TYPICAL RECOMMENDED LAND PATTERN  
Drawing No. : POD-00000098  
Revision: B  
REV1A  
13/15  
SPX2954  
Package Description (Continued)  
SOIC-8  
Top View  
Side View  
Front View  
Drawing No:  
POD-00000108  
Revision:  
A
REV1A  
14/15  
SPX2954  
Ordering Information(1)  
Operating Temperature  
Packaging  
Method  
Output Voltage  
(V)  
Part Number  
Lead-Free  
Yes(2)  
Package  
Accuracy  
Range  
SPX2954AM3-L-5-0/TR  
SPX2954M3-L-3-3/TR  
SPX2954M3-L-5-0/TR  
SPX2954M3-L-3-3(3)  
Reel  
Reel  
Reel  
Tube  
Reel  
0.5%  
1%  
5.0  
3.3  
5.0  
3.3  
5.0  
SOT-223-3  
SOIC-8  
-40°C ≤ T ≤ 125°C  
1%  
J
1%  
SPX2954AS-L-5-0/TR(3)  
0.5%  
NOTE:  
1. Refer to www.exar.com/SPX2954 for most up-to-date Ordering Information.  
2. Visit www.exar.com for additional information on Environmental Rating.  
3. NRND - Not Recommended for New Design.  
4. TO-220, TO-92, and TO-263 package options no longer available.  
Revision History  
Revision  
1A  
Date  
Description  
Updated to Maxlinear logo. Updated format and ordering information table. Pin configurations  
moved to page 4. Removed information related to packages no longer available.  
July 2017  
Corporate Headquarters:  
5966 La Place Court  
Suite 100  
Carlsbad, CA 92008  
Tel.:+1 (760) 692-0711  
Fax: +1 (760) 444-8598  
www.maxlinear.com  
High Performance Analog:  
48720 Kato Road  
Fremont, CA 94538  
Tel.: +1 (510) 668-7000  
Fax: +1 (510) 668-7001  
Email: powertechsupport@exar.com  
www.exar.com  
The content of this document is furnished for informational use only, is subject to change without notice, and should not be construed as a commitment by MaxLinear, Inc.. MaxLinear, Inc. assumes  
no responsibility or liability for any errors or inaccuracies that may appear in the informational content contained in this guide. Complying with all applicable copyright laws is the responsibility of the  
user. Without limiting the rights under copyright, no part of this document may be reproduced into, stored in, or introduced into a retrieval system, or transmitted in any form or by any means (electronic,  
mechanical, photocopying, recording, or otherwise), or for any purpose, without the express written permission of MaxLinear, Inc.  
Maxlinear, Inc. does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support  
system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless MaxLinear, Inc. receives, in writing, assurances to its satisfaction that: (a) the  
risk of injury or damage has been minimized; (b) the user assumes all such risks; (c) potential liability of MaxLinear, Inc. is adequately protected under the circumstances.  
MaxLinear, Inc. may have patents, patent applications, trademarks, copyrights, or other intellectual property rights covering subject matter in this document. Except as expressly provided in any written  
license agreement from MaxLinear, Inc., the furnishing of this document does not give you any license to these patents, trademarks, copyrights, or other intellectual property.  
Company and product names may be registered trademarks or trademarks of the respective owners with which they are associated.  
© 2017 MaxLinear, Inc. All rights reserved  
REV1A  
SPX2954_DS_072017  
15/15  

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