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January 2004s
LOW DROPOUT VOLTAGE (450mV Typ.at 1A)
s VERY LOW QUIESCENT CURRENT s THERMAL SHUTDOWN s SHORT CIRCUIT PROTECTION s
REVERSE POLARITY PROTECTION
DESCRIPTION
The L4941is a three terminal 5V positive regulators available in TO-220,TO-220FP and D 2PAK packages,making it useful in a wide range of industrial and consumer applications.Thanks to its very low input/output voltage drop,these devices are particularly suitable for battery powered equipments,reducing consumption and prolonging battery life.It employs internal current limiting,antisaturation circuit,thermal shut-down and safe area protection.
L4941
VERY LOW DROP 1A
REGULATOR
L4941
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ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings are those values beyond which damage to the device may occur.Functional operation under these condition is not implied.
THERMAL DATA
CONNECTION DIAGRAM (top view)
ORDERING CODES
(*)Available in Tape &Reel with the suffix "-TR".
Symbol Parameter
Value Unit V I Forward Input Voltage
30V V IR Reverse Input Voltage (R O =100?)-15
V I O Output Current Internally Limited mA P D Power Dissipation
Internally Limited mW T stg Storage Temperature Range
-40to +150°C T op
Operating Junction Temperature Range
-40to +150
°C
Symbol Parameter
TO-220TO-220FP
D 2PAK DPAK Unit R thj-case Thermal Resistance Junction-case 3538°C/W R thj-amb
Thermal Resistance Junction-ambient
50
60
62.5
100
°C/W
ORDERING CODE
PACKAGE L4941BV TO-220L4941BP TO-220FP L4941BD2T D 2PAK L4941BDT (*)
DPAK
L4941
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TEST CIRCUITS Figure 1:DC Parameter
Figure 2:Load Rejection
Figure 3:Ripple
Rejection
L4941
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ELECTRICAL CHARACTERISTICS (Refer to test circuit,V I =7V,C I =0.1μF,C O =22μF,T J =25°C,unless otherwise specified.)
TYPICAL CHARACTERISTICS
Figure 4:Dropout Voltage vs Output Current
Figure 5:Dropout Voltage vs Temperature
Symbol Parameter
Test Conditions
Min.Typ.Max.Unit V O Output Voltage I O =5mA to 1A
V I =6to 14V
4.8
5
5.2V V I Input Voltage I O =5mA 16V ?V O Line Regulation V I =6to 16V I O =5mA
520mV ?V O Load Regulation I O =5mA to 1A 820mV
I O =0.5A to 1A 515mV I q Quiescent Current I O =5mA V I =6V 48mA I O =1A V I =6V 20
40mA ?I q Quiescent Current Change I O =5mA V I =6to 14V 3mA I O =1A V I =6to 14V
-10mA V d
Dropout Voltage
I O =0.5A 250450mV I O =1A
450700
mV ?V O /?T Output Voltage Drift 0.6mv/°C SVR Supply
Voltage Rejection f =120Hz I O =1A
58
68dB I sc Short Circuit Current V I =14V 1.6 2.0A
V I =6V 1.8 2.2
Z O Output Impedance f =1KHz
I O =0.5A
30m ?e N
Output Noise Voltage
B =100Hz to 100KHz
30
μV/V O
L4941
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Figure 6:Output Voltage vs Temperature
Figure 7:Quiescent Current vs Temperature Figure 8:Quiescent Current vs Input Voltage
Figure 9:Quiescent Current vs Output Current
Figure 10:Short Circuit Current vs Temperature
Figure 11:Peak Output Current vs Input/Output Differential
Voltage
L4941
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Figure 12:Low Voltage Behavior
Figure 13:Supply Voltage Rejection vs Frequency
Figure 14:Supply Voltage Rejection vs Output Current
Figure 15:Load Dump Characteristics
Figure 16:Line Transient Response
Figure 17:Total Power
Dissipation
L4941
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Figure 18:Load transient Response
Figure 19:Distributed Supply with On-card L4940and L4941low drop
regulator
L4941
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Figure 20:Distributed Supply with On-card L4940and L4941low drop regulator
ADVANTAGES OTF THESE APPLICATION ARE:
On card regulation with short-circuit and thermal protection on each output.
Vary high total system efficency due to the switching preregulation and very low-drop
postregulation
L4941
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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