L6925D Datasheet, PDF (1/5 Pages) STMicroelectronics – HIGH EFFICIENCY MONOLITHIC SYNCHRONOUS STEP DOWN REGULATOR

L6925D
HIGH EFFICIENCY MONOLITHIC SYNCHRONOUS
STEP DOWN REGULATOR
s 2.7V TO 5.5V BATTERY INPUT RANGE
s HIGH EFFICIENCY: UP TO 95%
s INTERNAL SYNCHRONOUS SWITCH
s NO EXTERNAL SCHOTTKY REQUIRED
s EXTREMELY LOW QUIESCENT CURRENT
s 800mA MAX OUTPUT CURRENT
s ADJUSTABLE OUTPUT VOLTAGE FROM 0.6V
s LOW DROP-OUT OPERATION: UP TO100%
DUTY CYCLE
s SELECTABLE LOW NOISE/LOW
CONSUMPTION MODE AT LIGHT LOAD
s LOW BATTERY INPUT
s LOW BATTERY OUTPUT
s ±1% OUTPUT VOLTAGE ACCURACY
s CURRENT-MODE CONTROL
s 600kHz SWITCHING FREQUENCY
s EXTERNALLY SYNCHRONIZABLE FROM
500kHz TO 1.4MHz
s OVP
s SHORT CIRCUIT PROTECTION
APPLICATIONS
s BATTERY-POWERED EQUIPMENTS
s PORTABLE INSTRUMENTS
s CELLULAR PHONES
s PDAs AND HAND HELD TERMINALS
s DSC
s GPS
APPLICATION TEST CIRCUIT
MSOP8
ORDERING NUMBERS: L6925D (Tube)
L6925013TR (Tape & Reel)
DESCRIPTION
The device is dc-dc monolithic regulator specifically
designed to provide extremely high efficiency.
The device has on UVLO set at 2.7V cause it is part-
icurarly thought for single Li-ion cell applications.
Output voltage can be selected by an external divider
down to 0.6V. Duty Cycle can saturate to 100% al-
lowing low drop-out operation. The device is based
on a 600kHz fixed-frequency, current mode-architec-
ture. Low Consumption Mode operation can be se-
lected at light load conditions, allowing switching
losses to be reduced. L6925D is externally synchro-
nizable with a clock which makes it useful in noise-
sensitive applications. LBI pin can be used to have a
LBO signal when the Battery voltage is lower than a
preset value. Other features like, Overvoltage protec-
tion, Shortcircuit protection and Thermal Shutdown
(150°C) are also present.
V_IN=2.7V to 5.5V
C1
10µF
6.3V
SYNC
7
R2
V_CC
6
600K
LBI
1
R1
100K LBO ⁸
2
COMP
D01IN1238B
C2
220pF
L 6.8µH
5
LX
R4
200K
VFB
3
4
GND
R3
100K
V_OUT=1.8V
C4
10µF
6.3V
September 2003
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