CS51031 Datasheet, PDF (1/12 Pages) Cherry Semiconductor Corporation – Fast PFET Buck Controller Does Not Require Compensation

CS51031
Fast PFET Buck Controller
The CS51031 is a switching controller for use in DC–DC
converters. It can be used in the buck topology with a minimum
number of external components. The CS51031 consists of a V_CC
monitor for controlling the state of the device, 1.0 A power driver for
controlling the gate of a discrete P–channel transistor, fixed frequency
oscillator, short circuit protection timer, programmable soft start,
precision reference, fast output voltage monitoring 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 an 8 Lead SO plastic package.
Features
• 1.0 A Totem Pole Output Driver
• High Speed Oscillator (700 kHz max)
• No Stability Compensation Required
• Lossless Short Circuit Protection
• V_CC Monitor
• 2.0% Precision Reference
• Programmable Soft Start
• Wide Ambient Temperature Range:
– Industrial Grade: –40°C to 85°C
– Commercial Grade: 0°C to 70°C
5.0 V–12 V
C_IN
47 µF
V_GATE
V_GATE
V_C
PGND
CS
C_OSC
C_OSC
470 pF
GND
V_CC
V_FB
RV_CC
100 Ω
CV_CC
0.1 µF
MBRS360
D₁
MP₁
IRF7416
CS
0.1 µF
R_B
2.5 kΩ
L
4.7 µH
V_O
3.3 V @ 3 A
R_A
1.5 kΩ
C_RR
0.1 µF
C_O
100 µF × 2
http://onsemi.com
MARKING
DIAGRAM
8
8
1
SO–8
D SUFFIX
CASE 751
51031
ALYW
1
A
= Assembly Location
WL, L = Wafer Lot
YY, Y = Year
WW, W = Work Week
PIN CONNECTIONS
1
V_GATE
PGND
C_OSC
GND
V_C
CS
V_CC
V_FB
ORDERING INFORMATION*
Device
Package
Shipping
CS51031YD8
SO–8
95 Units/Rail
CS51031YDR8
SO–8 2500 Tape & Reel
CS51031GD8
SO–8
95 Units/Rail
CS51031GDR8
SO–8 2500 Tape & Reel
*Additional ordering information can be found on
page 9 of this data sheet.
Figure 1. Typical Application Diagram
© Semiconductor Components Industries, LLC, 2002
1
December, 2001 – Rev. 9
Publication Order Number:
CS51031/D