L6925D_04 Datasheet, PDF (1/6 Pages) STMicroelectronics – HIGH EFFICIENCY MONOLITHIC SYNCHRONOUS STEP DOWN REGULATOR

L6925D
HIGH EFFICIENCY MONOLITHIC SYNCHRONOUS
STEP DOWN REGULATOR
1 FEATURES
■ 2.7V TO 5.5V BATTERY INPUT RANGE
■ HIGH EFFICIENCY: UP TO 95%
■ INTERNAL SYNCHRONOUS SWITCH
■ NO EXTERNAL SCHOTTKY REQUIRED
■ EXTREMELY LOW QUIESCENT CURRENT
■ 800mA MAX OUTPUT CURRENT
■ ADJUSTABLE OUTPUT VOLTAGE FROM 0.6V
■ LOW DROP-OUT OPERATION: UP TO100%
DUTY CYCLE
■ SELECTABLE LOW NOISE/LOW
CONSUMPTION MODE AT LIGHT LOAD
■ LOW BATTERY INPUT
■ LOW BATTERY OUTPUT
■ ±1% OUTPUT VOLTAGE ACCURACY
■ CURRENT-MODE CONTROL
■ 600kHz SWITCHING FREQUENCY
■ EXTERNALLY SYNCHRONIZABLE FROM
500kHz TO 1.4MHz
■ OVP
■ SHORT CIRCUIT PROTECTION
1.1 APPLICATIONS
■ BATTERY-POWERED EQUIPMENTS
■ PORTABLE INSTRUMENTS
■ CELLULAR PHONES
■ PDAs AND HAND HELD TERMINALS
■ DSC
■ GPS
Figure 2. Application Test Circuit
Figure 1. Package
MSOP8
Table 1. Order Codes
Part Number
L6925D
L6925D013TR
Package
MSOP8 (Tube)
Tape & Reel
2 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-architecture. Low Consumption Mode
operation can be selected at light load conditions, al-
lowing switching losses to be reduced. L6925D is ex-
ternally synchronizable 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 protection, 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 2004
Rev. 3
1/6