PM6675A Datasheet, PDF (1/15 Pages) STMicroelectronics – Latched OVP and UVP

PM6675A
High efficiency step-down controller
with embedded 2A LDO regulator
Target Specification
Features switching
■ Switching section
– 4.5V to 36V input voltage range
– 0.6V, ±1% voltage reference
– Selectable 1.5V fixed output voltage
– Adjustable 0.6V to 3.3V output voltage
– 1.237V ±1% reference voltage available
VFQFPN-24 4x4
– Very fast load transient response using
constant-on-time control loop
t(s) – No RSENSE current sensing using low side
MOSFETs' R_DS(ON)
uc ^{– Negative current limit}
d _{– Latched OVP and UVP}
ro _{– Soft start internally fixed at 3ms}
P _{– Selectable pulse skipping at light load}
te ^{– Selectable No-Audible (33KHz) pulse skip}
le ^mode
o _{– Ceramic output capacitors supported}
bs ^{– Output voltage ripple compensation}
O ^{– Output soft-end}
- _{■ LDO regulator section}
t(s) ^{– Adjustable 0.6V to 2.5V output voltage}
– Selectable ±1Apk or ±2Apk current limit
uc ^{– Dedicated power-good signal}
d _{– Ceramic output capacitors supported}
ro – Output soft-end
te ^{P Applications}
le _{■ Industrial application on 24V}
so _{■ Graphic cards}
Ob^{■ Embedded computer systems}
Description
The PM6675A device consists of a single high
efficiency step-down controller and an
independent Low Drop-Out (LDO) linear
regulator.
The Constant On-Time (COT) architecture
assures fast transient response supporting both
electrolytic and ceramic output capacitors. An
embedded integrator control loop compensates
the DC voltage error due to the output ripple.
Selectable low-consumption mode allows the
highest efficiency over a wide range of load
conditions. The low-noise mode sets the minimum
switching frequency to 33kHz for audio-sensitive
applications. The LDO linear regulator can sink
and source up to 2Apk. Two fixed current limit
(±1A- ±2A) can be chosen.
An active Soft-End is independently performed on
both the switching and the linear regulators
outputs when disabled.
Order codes
Part number
PM6675A
Package
VFQFPN-24 4x4 (Exposed Pad)
Packaging
Tube
October 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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