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Details, datasheet, quote on part number:LM338P
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Datasheet text preview:
LT138A/LT338A LM138/LM338 5A Positive Adjustable Voltage Regulator
FEATURES
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DESCRIPTIO
Guaranteed 1% Initial Tolerance Guaranteed 0.3% Load Regulation Guaranteed 5A Output Current 100% Thermal Limit Burn-In 12A Transient Output Current
APPLICATIO S
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High Power Linear Regulator Battery Chargers Power Driver Constant-Current Regulator
The LT®138A series of adjustable regulators provide 5A output current over an output voltage range of 1.2V to 32V. The internal voltage reference is trimmed to less than 1%, enabling a very tight output voltage. In addition to excellent line and load regulation, with full overload protection, the LT138A incorporates new current limiting circuitry allowing large transient load currents to be handled for short periods. Transient load currents of up to 12A can be supplied without limiting, eliminating the need for a large output capacitor. The LT138A is an improved version of the popular LM138 with improved circuit design and advanced process techniques to provide superior performance and reliability. The graph below shows the significant improvement in output voltage tolerance achieved by using the LT138A or LT338A.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
Parallel Regulators for Higher Current*
12
LT338A VIN VIN ADJ VOUT
0.01**
OUTPUT VOLTAGE ERROR (%)
5V 8A
11 10 9 8 7 6 5 4 3 2 1 0 1% RESISTORS 2% RESISTORS LT338A 2% RESISTORS 1% RESISTORS LM338 LM338 LT338A
LT350A VIN ADJ VOUT
0.016** 121 1% 365 1%
138/338 TA01
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*THIS CIRCUIT WILL NOT WORK WITH LM VERSION DEVICES **CURRENT SHARING RESISTORS DEGRADE REGULATION TO 1%
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Output Voltage Error
10 OUTPUT VOLTAGE (V) 100
138A/338A TA02
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U
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LT138A/LT338A LM138/LM338 ABSOLUTE AXI U RATI GS
Power Dissipation ...... Internally Limited Input-to-Output Voltage Differential ...... 35V Operating Junction Temperature Range LT138A/LM138 ....... 55°C to 150°C LT338A/LM338 .. 0°C to 125°C
PRECONDITIONI G
100% Thermal Limit Burn-In
PACKAGE/ORDER I FOR ATIO
BOTTOM VIEW VIN 2 CASE IS OUTPUT 1 ADJ K PACKAGE 2-LEAD TO-3 METAL CAN
TJMAX = 150°C, JA = 35°C/ W, JC = 1°C/ W (LT138A/LT138) TJMAX = 125°C, JA = 35°C/ W, JC = 1°C/ W (LT338A/LT338)
ORDER PART NUMBER LT138AK LT338AK LM138K LM338K
FRONT VIEW 3 2 1 P PACKAGE 3-LEAD PLASTIC TO-3P VOUT VIN ADJ
TJMAX = 125°C, JA = 45°C/ W
OBSOLETE PACKAGE
Consider the P Package for Alternate Source
Consult LTC Marketing for parts specified with wider operating temperature ranges.
The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 2)
SYMBOL V REF PARAMETER Reference Voltage CONDITIONS IOUT = 10mA, TJ = 25°C 3V (VIN VOUT) 35V, 10mA IOUT 5A, P 50W VOUT VIN VOUT IOUT Line Regulation Load Regulation 3V (VIN VOUT) 35V, (Note 3)
q q
ELECTRICAL CHARACTERISTICS
MIN 1.238 1.225
LT138A TYP MAX 1.250 1.250 0.005 0.02 5 0.1 1.262 1.270 0.01 0.04 15 0.3 30 0.6 0.01
10mA IOUT 5A, (Note 3) VOUT 5V VOUT 5V VOUT 5V VOUT 5V
q q
20 0.3 0.002
Thermal Regulation Ripple Rejection
20ms Pulse VOUT = 10V, f = 120Hz CADJ = 0µF CADJ = 10µF 10mA IOUT 5A, 3V (VIN VOUT) 35V (VIN VOUT) = 35V
q q q q q
60
60 75 45 0.2 3.5 100 5 5
I ADJ IADJ
Adjust Pin Current Adjust Pin Current Change Minimum Load Current
2
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U
U
U
W
WW
U
W
(Note 1)
Storage Temperature Range ....... 65°C to 150°C Lead Temperature (Soldering, 10 sec)........ 300°C
ORDER PART NUMBER LM338P
MIN 1.19
LM138 TYP 1.24 0.005 0.02 5 0.1 20 0.3 0.002 60 75 45 0.2 3.5
MAX 1.29 0.01 0.04 15 0.3 30 0.6 0.01
UNITS V V %/V %/V mV % mV % %/W dB dB
60
100 5 5
µA µA mA
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LT138A/LT338A LM138/LM338
ELECTRICAL CHARACTERISTICS
SYMBOL I SC PARAMETER Current Limit CONDITIONS (VIN VOUT) 10V DC 0.5ms Peak (VIN VOUT) = 30V, TJ = 25°C V OUT Temp V OUT Time en JC Temperature Stability Long-Term Stability TA = 125°C, 1000 Hours
q q q
The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 2)
MIN 5 6 LT138A TYP MAX 8 12 1 1 0.3 0.001 1 2 2 1 MIN 5 6 LM138 TYP 8 12 1 1 0.3 0.003 1 1 MAX UNITS A A A % % % °C/W
RMS Output Noise (% of VOUT) 10Hz f 10kHz Thermal Resistance Junction-to-Case K Package
The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 2)
SYMBOL V REF PARAMETER Reference Voltage CONDITIONS IOUT = 10mA 3V (VIN VOUT) 35V, 10mA IOUT 5A, P 50W V OUT VIN V OUT IOUT Line Regulation Load Regulation 3V (VIN VOUT) 35V, (Note 3)
q q
MIN 1.238 1.225
LT338A TYP MAX 1.250 1.250 0.005 0.02 5 0.1 1.262 1.270 0.01 0.04 15 0.3 30 0.6 0.02
MIN 1.19
LM338 TYP 1.24 0.005 0.02 5 0.1 20 0.3 0.002 60 75 45 0.2 3.5
MAX 1.29 0.03 0.06 25 0.5 50 1 0.02
UNITS V V %/V %/V mV % mV % %/W dB dB
10mA IOUT 5A, (Note 3) VOUT 5V VOUT 5V VOUT 5V VOUT 5V
q q
20 0.3 0.002
Thermal Regulation Ripple Rejection
20ms Pulse VOUT = 10V, f = 120Hz CADJ = 0µF CADJ = 10µF 10mA IOUT 5A, 3V (VIN VOUT) 35V (VIN VOUT) = 35V (VIN VOUT) 10V DC 0.5ms Peak (VIN VOUT) = 30V, TJ = 25°C
q q q q q q q
60
60 75 45 0.2 3.5 100 5 10
60
I ADJ IADJ
Adjust Pin Current Adjust Pin Current Change Minimum Load Current
100 5 10
µA µA mA A A A %
I SC
Current Limit
5 6
8 12 1 2 2 1 1 0.3 0.001 1
5 6
8 12 1 1 0.3 0.003 1 1
VOUT Temp V OUT Time en JC
Temperature Stability Long-Term Stability RMS Output Noise (% of VOUT) Thermal Resistance Junction-to-Case TA = 125°C, 1000 Hours 10Hz f 10kHz K Package
q
% % °C/W
Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note 2: Unless otherwise specified, these specifications apply: VIN VOUT = 5V and IOUT = 2.5A. These specifications are applicable for power dissipations up to 50W.
Note 3: See thermal regulation specifications for changes in output voltage due to heating effects. Load and line regulation are measured at a constant junction temperature by low duty cycle pulse testing.
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