CS51031 Datasheet, PDF (1/8 Pages) Cherry Semiconductor Corporation – Fast PFET Buck Controller Does Not Require Compensation

CS51031
Fast PFET Buck Controller
Does Not Require Compensation
Description
Features
The CS51031 is a switching con-
troller for use in DC-DC converters.
It can be used in the buck topology
with a minimum number of exter-
nal components. The CS51031 con-
sists of a V_CC monitor for control-
ling the state of the device, 1.0A
power driver for controlling the
gate of a discrete P-channel transis-
tor, fixed frequency oscillator, short
circuit protection timer, pro-
grammable soft start, precision ref-
erence, fast output voltage monitor-
ing comparator, and output stage
driver logic with latch.
The high frequency oscillator
allows the use of small inductors
and output capacitors, minimizing
PC board area and systems cost.
The programmable soft start
reduces current surges at start up.
The short circuit protection timer
significantly reduces the duty cycle
to approximately 1/30 of its cycle
during short circuit conditions.
The CS51031 is available in 8L SO
and 8L PDIP plastic packages.
s 1A Totem Pole Output
Driver
s High Speed Oscillator
(700kHz max)
s No Stability
Compensation Required
s Lossless Short Circuit
Protection
s V_CC Monitor
s 2% Precision Reference
s Programmable Soft Start
Typical Application Diagram
5V - 12V
C_IN
47mF
V_GATE
V_GATE
V_C
C_OSC
150pF
PGnd
CS
CS51031
C_OSC
V_CC
Gnd
V_FB
20W
MP₁
IRF7416
RV_CC
10W
CV_CC
100mF
100
.01mF
CS
0.1mF
MBRS360
D₁
L
4.7mH
R_B
2.5kW
V_O
3.3V @ 3A
R_A
1.5kW
C_RR
0.1mF
C_O
100mF ´ 2
Package Options
8 Lead SO Narrow & PDIP
V_GATE 1
PGnd
C_OSC
Gnd
V_C
CS
V_CC
V_FB
Rev. 2/13/98
Cherry Semiconductor Corporation
2000 South County Trail, East Greenwich, RI 02818
Tel: [phone] Fax: [phone]
Email: [e-mail]
Web Site: www.cherry-semi.com
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