L6926_08 Datasheet, PDF (1/16 Pages) STMicroelectronics – High efficiency monolithic synchronous step down regulator

L6926
High efficiency monolithic synchronous step down regulator
Features
■ 2 V to 5.5 V battery input range
■ High efficiency: up to 95 %
■ Internal synchronous switch
■ No external schottky required
■ Extremely low quiescent current
■ 1 mA max shutdown supply current
■ 800 mA max output current
■ Adjustable output voltage from 0.6 V
■ Low drop-out operation: up to 100 % duty cycle
■ Selectable low noise/low consumption mode at
light load
■ Power good signal
■ ±1 % output voltage accuracy
■ Current-mode control
■ 600 kHz switching frequency
■ Externally synchronizable
from 500 kHz to 1.4 MHz
■ OVP
■ Short circuit protection
Applications
■ Battery-powered equipments
■ Portable instruments
■ Cellular phones
■ PDAs and hand held terminals
■ DSC
■ GPS
Figure 1. Application test circuit
MSOP8
VFQFPN8
(3x3x1.0 mm)
Description
The device is DC-DC monolithic regulator
specifically designed to provide extremely high
efficiency.
L6926 supply voltage can be as low as 2 V
allowing its use in single Li-ion cell supplied
applications. Output voltage can be selected by
an external divider down to 0.6 V.
Duty cycle can saturate to 100 % allowing low
drop-out operation.
The device is based on a 600 kHz fixed-
frequency, current mode-architecture.
Low consumption mode operation can be
selected at light load conditions, allowing
switching losses to be reduced. L6926 is
externally synchronizable with a clock which
makes it useful in noise-sensitive applications.
Other features like powergood, overvoltage
protection, shortcircuit protection and thermal
shutdown (150 °C) are also present.
September 2008
V_IN=2V to 5.5V
C1
10μF
6.3V
SYNC
7
V_CC
6
RUN
1
2
COMP
D01IN1305
C2
220pF
L 6.8μH
5
LX
R3
500K
8
PGOOD
3
4
VFB
GND
Rev 8
R2
200K
R1
100K
V_OUT=1.8V
C4
10μF
6.3V
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