CS51021A, CS51022A,
CS51023A, CS51024A
Enhanced Current Mode
PWM Controller
The CS51021A/2A/3A/4A Fixed Frequency PWM Current Mode
Controller family provides all necessary features required for AC−DC
or DC−DC primary side control. Several features are included
eliminating the additional components needed to implement them
externally. In addition to low startup current (75 mA) and high
frequency operation capability, the CS51021A/2A/3A/4A family
includes overvoltage and undervoltage monitoring, externally
programmable dual threshold overcurrent protection, current sense
leading edge blanking, current slope compensation, accurate duty cycle
control and an externally available 5.0 V reference. The CS51021A
and CS51023A feature bidirectional synchronization capability, while
the CS51022A and CS51024A offer a sleep mode with 100 mA
maximum IC current consumption. The CS51021A/2A/3A/4A family
is available in a 16 lead narrow body SOIC package.
http://onsemi.com
SOIC−16
D SUFFIX
CASE 751B
16
1
TSSOP−16
DTB SUFFIX
CASE 948F
16
1
Device
CS51021A
Sleep/Synch
Synch
V
Start/Stop
CC
PIN CONNECTIONS AND
MARKING DIAGRAMS
8.25 V/7.7 V
8.25 V/7.7 V
13 V/7.7 V
13 V/7.7 V
CS51022A
CS51023A
CS51024A
Sleep
Synch
16
1
GATE
V
C
Sleep
I
PGND
SENSE
SLEEP or SYNC
V
V
CC
SLOPE
UV
REF
Features
LGND
SS
• 75 mA Max. Startup Current
OV
• Fixed Frequency Current Mode Control
• 1.0 MHz Switching Frequency
• Undervoltage Protection Monitor
R C
COMP
V
FB
T
T
I
SET
1
16
• Overvoltage Protection Monitor with Programmable Hysteresis
• Programmable Dual Threshold Overcurrent Protection with
Delayed Restart
• Programmable Soft Start
• Accurate Maximum Duty Cycle Limit
• Programmable Slope Compensation
• Leading Edge Current Sense Blanking
• 1.0 A Sink/Source Gate Drive
x
A
= Specific Device Code
= Assembly Location
WL, L = Wafer Lot
= Year
Y
WW, W = Work Week
G or G = Pb−Free Package
• Bidirectional Synchronization (CS51021A/3A)
• 50 ns PWM Propagation Delay
• 100 mA Max Sleep Current (CS51022A/4A)
• Pb−Free Packages are Available*
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 9 of this data sheet.
*For additional information on our Pb−Free strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques
Reference Manual, SOLDERRM/D.
©
Semiconductor Components Industries, LLC, 2006
1
Publication Order Number:
February, 2006 − Rev. 8
CS51021A/D