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April 2003s
非共价键GUARANTEED 7A PEAK OUTPUT CURRENT
s GUARANTEED 5A OUTPUT CURRENT s ADJUSTABLE OUTPUT DOWN TO 1.2V s LINE REGULATION TYPICALLY 0.005%/V s LOAD REGULATION TYPICALLY 0.1%s GUARANTEED THERMAL REGULATION s
CURRENT LIMIT CONSTANT WITH TEMPERATURE
s
STANDARD 3-LEAD TRANSISTOR PACKAGE
DESCRIPTION The LM138/LM238/LM338are adjustable 3-terminal positive voltage regulators capable of supplying in excess of 5A over a 1.2V to 32V output range.They are exceptionally easy to u and re
quire only 2resistors to t the output voltage.Careful circuit design has resulted in outstanding load and line regulation comparable to many commercial power supplies.The LM138family is supplied in a standard 3-lead transistor package.
A unique feature of the LM138family is time-de-pendent current limiting.The current limit circuitry allows peak currents of up to 12A to be drawn from the regulator for short periods of time.This allows the LM138to be ud with heavy transient loads and speeds start-up under full-load conditions.Under sustained loading conditions,the current limit decreas to a safe value protecting the regulator.Also included on the chip are thermal overload protection and safe area protection for the power transistor.Overload protection remains functional even if the adjustment pin is accidentally disconnected.
Normally,no capacitors are needed unless the device is situated far from the input filter capacitors in which ca an input bypass is needed.An optional output capacitor can be added to improve transient respon.The adjustment terminal can be bypasd to achieve.very high ripple rejection ratios which are
LM138/LM238
LM338
THREE-TERMINAL 5A
ADJUSTABLE VOLTAGE
REGULATORS
LM138-LM238-LM338
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difficult to achieve with standard 3-terminal regulators.
Besides replacing fixed regulators or discrete designs,the LM238is uful in a wide variety of other applications.Since the regulator is "floating"and es only the input-to-output differential voltage,supplies of veral hundred volts can be regulated as long as the maximum input to input differential is not exceeded.
爸爸去哪儿阿拉蕾The LM138/LM238/LM338are packaged in standard steel TO-3transistor packages.The LM138is rated for operation from -55°C to 150°C,the LM238from –25°C to 150°C and the LM338from 0°C to 125°C.
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings are tho values beyond which damage to the device may occur.Functional operation under the condition is not implied.
THERMAL DATA
CONNECTION DIAGRAM (top view)
ORDERING CODES
Symbol Parameter
Value Unit V I -V O Input Output Voltage Differential
35
V
P tot Power Dissipation
明朝为什么会灭亡Internally Limited
T stg Storage Temperature Range
-65to 150°C T lead Lead Temperature (Soldering,10conds)300°C T oper
Operating Junction Temperature Range
LM138-55to 150°C LM238-25to 125LM338
0to 125
Symbol Parameter
Value Unit R thj-ca Thermal Resistance
Junction-ca 1.4°C/W R thj-amb了凡四训观后感
Thermal Resistance Junction-ambient
35
°C/W
TYPE TO-3TEMPERATURE RANGE
LM138LM138K -55°C to 150°C LM238LM238K -25°C to 150°C LM338
空调电扇LM338K
0°C to 125°C
LM138-LM238-LM338
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ELECTRICAL CHARACTERISTICS OF LM138/LM238(T J =-55to 150°C for LM138,
T J =-25to 150°C for LM238,V I -V O =5V,I O =2.5A.Although power dissipation is internally limited,the specifications apply to power dissipation up to 50W,unless otherwi specified).
Note 1:Regulation is measured at constant junction temperature.Changes in output voltage due to heating effects are taken into account parately by thermal rejection.
Symbol Parameter
Test Conditions Min.
Typ.Max.Unit K VI Line Regulation (Note 1)T a =25°C,
V I -V O =3to 35V
0.0050.01%/V K VO
Load Regulation (Note 1)T a =25°C
I O =10mA to 5A V O ≤5V 515mV V O ≥5V
0.10.3%Thermal Regulation Pul =20ms 0.0020.01%/W I adj Adjustment Pin Current 45100µA ∆I adj Adjustment Pin Current Change
I L =10mA to 5A
V I -V O =3to 35V
0.25µA V ref Reference Voltage V I -V O =3to 35V,I O =10mA to 5A P ≤50W
1.19 1.24 1.29V K VI Line Regulation (Note 1)V I -V O =3to 35V 0.020.04%/V K VO Load Regulation (Note 1)I O =10mA to 5A V O ≤5V 2030mV V O ≥5V
0.30.6
%K VT Temperature Stability T J =T min to T max 1%I O(min)Minimum Load Current V I -V O ≤35V 3.5
5mA I O(max)
Current Limit
V I -V O ≤10V
DC
激励短语58A
0.5ms Peak 7
12V I -V O =30V
1
V NO RMS Output Noi (%of V O )
T a =25°C
f =10Hz to 10KHz 0.003
%R vf Ripple Rejection Ratio V O =10V,f =120Hz 60
dB
C adj =10µF 60
75K VH
Long Term Stability
T a =125°C
0.3
无人机英文1
%
LM138-LM238-LM338
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ELECTRICAL CHARACTERISTICS OF LM338(T J =0to 150°C,V I -V O =5V,I O =2.5A.
Although power dissipation is internally limited,the specifications apply to power dissipation up to 50W,unless otherwi specified).
Note 1:Regulation is measured at constant junction temperature.Changes in output voltage due to heating effects are taken into account parately by thermal rejection.
Symbol Parameter
Test Conditions Min.
Typ.Max.Unit K VI Line Regulation (Note 1)T a =25°C,
V I -V O =3to 35V
0.0050.03%/V K VO
Load Regulation (Note 1)T a =25°C
I O =10mA to 5A V O ≤5V 525mV V O ≥5V
0.10.5%Thermal Regulation Pul =20ms 0.0020.02%/W I adj Adjustment Pin Current 45100µA ∆I adj Adjustment Pin Current Change
I L =10mA to 5A
V I -V O =3to 35V
0.25µA V ref Reference Voltage V I -V O =3to 35V,I O =10mA to 5A P ≤50W
1.19 1.24 1.29V K VI Line Regulation (Note 1)V I -V O =3to 35V 0.020.06%/V K VO Load Regulation (Note 1)I O =10mA to 5A V O ≤5V 2050mV V O ≥5V
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%K VT Temperature Stability T J =T min to T max 1%I O(min)Minimum Load Current V I -V O ≤35V 3.5
10mA I O(max)
Current Limit
V I -V O ≤10V
DC
58A
0.5ms Peak 7
12V I -V O =30V
1
V NO RMS Output Noi (%of V O )
T a =25°C
f =10Hz to 10KHz 0.003
%R vf Ripple Rejection Ratio V O =10V,f =120Hz 60
dB
C adj =10µF 60
75K VH
Long Term Stability
T a =125°C
0.3
1
%
LM138-LM238-LM338
银耳莲子红枣羹
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