Datasheet

December 2011 Doc ID 11051 Rev 7 1/16
16
L6928
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 µA max shutdown supply current
800 mA max output current
Adjustable output voltage from 0.6 V
Low dropout 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
1.4 MHz switching frequency
Externally synchronizable from 1 MHz to 2
MHz
OVP
Short-circuit protection
Applications
Battery-powered equipment
Portable instruments
Cellular phones
PDAs and hand held terminals
DSC
GPS
Description
The device is DC-DC monolithic regulator
specifically designed to provide extremely high
efficiency. L6928 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 dropout operation.
The device is based on a 1.4 MHz fixed
frequency, current mode architecture. Low
consumption mode operation can be selected at
light load conditions, allowing switching losses to
be reduced. L6928 is externally synchronizable
with a clock which makes it useful in noise
sensitive applications. Other features like Power
Good, overvoltage protection, short-circuit
protection and thermal shutdown (150 °C) are
also present.
VFQFPN8
MSOP8
(3x3x1.0 mm)
Figure 1. Application test circuit
AM10473v1
V
IN
= 2 to 5.5 V
V
IN
= 1.8 V
C1
10µF
6.3V
R1
100k
R3
500k
R2
200k
L 4.7 µH
C2
10µF
6.3V
C3
220pF
R1
10k
LX
PGOOD
VFB
GNDCOMP
V
CC
RUN
SYNC
5
8
3
7
1
6
24
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