cs51221 ON Semiconductor, cs51221 Datasheet - Page 6

• Manufacturer Part Number: cs51221
• Description: Enhanced Voltage Mode Pwm Controller
• Manufacturer: ON Semiconductor

PACKAGE PIN DESCRIPTION
Package
Pin #
10
12
13
14
15
16
11
1
2
3
4
5
6
7
8
9
Symbol
I
COMP
PGND
SYNC
LGND
GATE
SENSE
R
V
I
V
V
Pin
UV
OV
SET
SS
FF
V
T
REF
CC
FB
C
C
T
External power switch driver with 1.0 A peak capability. Rail to rail output occurs when the capacitive load is
between 470 pF and 10 nF.
Current sense comparator input.
Bidirectional synchronization. Locks to highest frequency.
PWM ramp.
Undervoltage protection monitor.
Overvoltage protection monitor.
Timing resistor R
Voltage at this pin sets pulse−by−pulse overcurrent threshold.
Feedback voltage input. Connected to the error amplifier inverting input.
Error amplifier output.
Charging external capacitor restricts error amplifier output voltage during the power up or fault conditions.
Logic ground.
3.3 V reference voltage output. Decoupling capacitor can be selected from 0.01 mF to 10 mF.
Logic supply voltage.
Output power stage ground.
Output power stage supply voltage.
T
and capacitor C
http://onsemi.com
T
determine oscillator frequency and maximum duty cycle, D
CS51221
6
Function
MAX
.