L5987 Datasheet, PDF (1/42 Pages) STMicroelectronics – 3 A step-down switching regulator

L5987
3 A step-down switching regulator
Preliminary Data
Features
■ 3 A DC output current
■ 2.9 V to 18 V input voltage
■ Output voltage adjustable from 0.6 V
■ 250 kHz switching frequency, programmable
up to 1 MHz
■ Internal soft-start and inhibit
■ Low dropout operation: 100 % duty cycle
■ Voltage feed-forward
■ Zero load current operation
■ Over current and thermal protection
■ VFQFPN3x3-8L and HSOP8 package
Applications
■ Consumer:
STB, DVD, DVD recorder, car audio, LCD TV
and monitors
■ Industrial:
PLD, PLA, FPGA, chargers
■ Networking: XDSL, modems, DC-DC modules
■ Computer:
Optical storage, hard disk drive, printers,
audio/graphic cards
■ LED driving
VFQFPN8 3x3 mm HSOP8 exposed pad
Description
The L5987 is a step down switching regulator with
3.5 A (minimum) current limited embedded power
MOSFET, so it is able to deliver up to 3 A current
to the load depending on the application
conditionals Section 5.7 and Section 5.8).
The input voltage can range from 2.9 V to 18 V,
while the output voltage can be set starting from
0.6 V to V_IN. Having a minimum input voltage of
2.9 V, the device is suitable also for 3.3 V bus.
Requiring a minimum set of external components,
the device includes an internal 250 kHz switching
frequency oscillator that can be externally
adjusted up to 1 MHz.
The QFN and the HSOP package with exposed
pad allow reducing the R_thJA down to 60 °C/W
and 40 °C/W respectively.
Figure 1. Application circuit
August 2008
Rev 1
This is preliminary information on a new product now in development or undergoing evaluation.
Details are subject to change without notice.
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