L4957AD1.8 ,UP TO 5A ULTRA LOW DROP OUPUT LINEAR REGULATORAPPLICATIONSL4957AV1.5 L4957AD1.5L4957AV1.8 L4957AD1.8M ..
L4957AD-1.8 ,UP TO 5A ULDO LINEAR REGULATORAPPLICATIONSL4957AV1.5 L4957AD1.5L4957AV1.8 L4957AD1.8MOTHER BOARDSL4957AV2.5 L4957AD2.5L4957AV3.3 ..
L4957AD1.8TR ,UP TO 5A ULTRA LOW DROP OUPUT LINEAR REGULATORBLOCK DIAGRAMINVIN110m FCHARGECURRENTPUMPVREFLIMIT+ BUFFER POWERPREE/ADMOSREGULATOR-200mWOUTTHERMAL ..
L4957AD-1.8TR ,UP TO 5A ULTRA LOW DROP OUPUT LINEAR REGULATORapplications. trolled short circuit current. Thermal shutdownprovides protection against overload c ..
L4957AD2.5 ,UP TO 5A ULTRA LOW DROP OUPUT LINEAR REGULATORABSOLUTE MAXIMUM RATINGSSymbol Parameter Value UnitV Supply Input Voltage 16 VINT Junction Temperat ..
L4957AD25TR ,UP TO 5A ULTRA LOW DROP OUPUT LINEAR REGULATORL4957A®UP TO 5A ULDO LINEAR REGULATOR1.5V, 1.8V, 2.5V AND 3.3V FIXED OUTPUTMULTIPOWER BCD TECHNOLOG ..
LBC2518T1R0M , WOUND CHIP INDUCTORS
LBC2518T1R0M , WOUND CHIP INDUCTORS
LBC2518T3R3M , WOUND CHIP INDUCTORS
LBC2518T4R7M , WOUND CHIP INDUCTORS
LBC2518T4R7M , WOUND CHIP INDUCTORS
LBC807-25LT1G , General Purpose Transistors PNP Silicon
L4957AD1.8-L4957AD2.5-L4957AD3.3-L4957AV1.5-L4957AV1.8-L4957AV2.5-L4957AV3.3
UP TO 5A ULTRA LOW DROP OUPUT LINEAR REGULATOR
L4957AUP TO 5A ULDO LINEAR REGULATOR
1.5V, 1.8V, 2.5V AND 3.3V FIXED OUTPUT
VOLTAGE
3V TO 14V INPUT VOLTAGE RANGE
200mΩ Rdson TYPICAL @ Tj = 125°C
0.6V max. DROP-OUT AT 2A
EXCELLENT LOAD REGULATION
0.6mA QUIESCENT CURRENT AT ANY LOAD
SHORT CIRCUIT PROTECTION
THERMAL SHUTDOWN
APPLICATIONSMOTHER BOARDS
PROCESSOR I/O & SUPPLIES
LOW VOLTAGE MEMORY & CHIP SET SUP-
PLIES
GRAPHIC & SOUND CARDS
LOW VOLTAGE LOGIC SUPPLIES
POST REGULATOR FOR SMPS
DESCRIPTIONThe L4957A devices are
Ultra Low Drop Outputlinear regulators with an internal N-channel MOS
of 200mΩ particulary suitable for low voltage/low
dropout applications.
Operating with a input voltage from 3V to 14V
they are capable to deliver up to 5A.
The devices are ideal for use as one of the sup-
plies required by processor, for example they are
the cost effective and efficient solution for conver-
sion from 3.3V (rail bus) to 2.5V @ 2.5A or to
1.5V with high current rating.
Fast response transient minimise the output ca-
pacitor value. A minimum of 22μF assures the
stability in all load conditions.
The on-chip trimming technique offers a tighter
voltage reference tolerance (with ± 2% including
line and load variation) beside to ensure a con-
trolled short circuit current. Thermal shutdown
provides protection against overload conditions
that creates excessive junction temperature.
TYPICAL APPLICATION
ABSOLUTE MAXIMUM RATINGS
PINS CONNECTION
BLOCK DIAGRAM
PIN FUNCTIONS
L4957A2/7
ELECTRICAL CHARACTERISTICS (Tj = 25°C, VIN = 5V, unless otherwise specified).• = Specifications referred to TJ from 0°C to +125°C.
THERMAL DATA-40 -20 0 20 40 60 80 100 120 140 1600
t V
eviat
Figure 1: Line Regulation vs. Junction
Temperature 2345-5
Iout [A]
t V
lta
tio
[m
Figure 2: Load Regulation
L4957A3/7
*Pulsed tecnique has been used
-40 -20 0 20 40 60 80 100 120 140 1600
Tj [°C]
Output Current [A]
Figure 3: Maximum Output Current vs. JunctionTemperature 234 567 8
(Vin - Vout) [V] utput Current [A]
Figure 4: DC Operating AreaRipple R ejection [dB] 10 100
Figure 5: Ripple Rejection vs. Frequency6.3 IOUT(A)
VOUT
D00IN1109
Figure 6: Output Voltage vs. Output Current. 0.2 0.4 0.6 0.81 1.2 1.4 1.6 1.820
ΔV = Vin - Vo [A]
Figure 7: Maximum Output Current vs. Drop-OutVoltage
L4957A4/7
L4957A5/7
L4957A6/7
