PM6681A Datasheet, PDF (1/12 Pages) STMicroelectronics – Dual step-down controller with adjustable LDO

PM6681A
Dual step-down controller with adjustable LDO
Target Specification
Features
■ 6V to 36V input voltage range
■ Adjustable output voltages
■ 0.9-3.3V LDO adjustable delivers 100mA peak
current
■ 5V LDO delivers 100mA peak current
■ 1.237V ±1% reference voltage available
■ NO R_SENSE current sensing using low side
MOSFETs' R_DS(on)
■ Negative current limit
■ Soft start internally fixed at 2ms
■ Soft output discharge
■ Latched UVP
■ Not-latched OVP
■ Selectable pulse skipping at light loads
■ Selectable minimum frequency(33kHz) in
pulse skip mode
■ 5mW maximum quiescent power
■ Indipendent power good signals
■ Output voltage ripple compensation
Applications
■ Embedded computer system
■ FPGA system power
■ Industrial applications on 24V
■ High performance and high density DC/DC
modules
VFQFPN-32 (5mm x 5mm)
Description
PM6681A is a dual step-down controller
specifically designed to provide extremely high
efficiency conversion, with lossless current
sensing technique. The constant on-time
architecture assures fast load transient response
and the embedded voltage feed-forward provides
nearly constant switching frequency operation. An
embedded integrator control loop compensates
the DC voltage error due to the output ripple.
Pulse skipping technique increases efficiency at
very light load. Moreover a minimum switching
frequency of 33kHz is selectable to avoid audio
noise issues. The PM6681A provides a selectable
switching frequency, allowing three different
values of switching frequencies for the two
switching sections. The output voltages OUT1
and OUT2 can be adjusted from 0.9V to 5V and
from 0.9V to 3.3V respectively. The device
provides also 2 LDOs, 5V fixed and 0.9V-3.3V
adjustable.
Order codes
Part number
PM6681A
PM6681ATR
Package
VFQFPN-32 (5mm x 5mm)
VFQFPN-32 (5mm x 5mm)
Packaging
Tube
Tape and Reel
November 2006
Rev 1
This is preliminary information on a new product foreseen to be developed. Details are subject to change without notice.
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