CS51221 Datasheet, PDF (1/14 Pages) Cherry Semiconductor Corporation – Enhanced Voltage Mode PWM Controller

CS51221
Enhanced Voltage Mode
PWM Controller
The CS51221 fixed frequency feed forward voltage mode PWM
controller contains all of the features necessary for basic voltage mode
operation. This PWM controller has been optimized for high
frequency primary side control operation. In addition, this device
includes such features as: Soft−Start, accurate duty cycle limit control,
less than 50mA startup current, over and undervoltage protection, and
bidirectional synchronization. The CS51221 is available in a 16 lead
SOIC narrow surface mount package.
Features
• 1.0 MHz Frequency Capability
• Fixed Frequency Voltage Mode Operation, with Feed Forward
• Thermal Shutdown
• Undervoltage Lock−Out
• Accurate Programmable Max Duty Cycle Limit
• 1.0 A Sink/Source Gate Drive
• Programmable Pulse−By−Pulse Overcurrent Protection
• Leading Edge Current Sense Blanking
• 75 ns Shutdown Propagation Delay
• Programmable Soft−Start
• Undervoltage Protection
• Overvoltage Protection with Programmable Hysteresis
• Bidirectional Synchronization
• 25 ns GATE Rise and Fall Time (1.0 nF Load)
• 3.3 V 3% Reference Voltage Output
• Pb−Free Packages are Available*
*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, 2005
1
September, 2005 − Rev. 8
http://onsemi.com
16
1
SOIC−16
D SUFFIX
CASE 751B
TSSOP−16
DTB SUFFIX
16
CASE 948F
1
PIN CONNECTIONS AND
MARKING DIAGRAM
1
GATE
I_SENSE
SYNC
FF
UV
OV
16
V_C
PGND
V_CC
V_REF
LGND
SS
R_TC_T
I_SET
COMP
V_FB
1
16
CS51221= Specific Device Code
A
= Assembly Location
WL, L = Wafer Lot
YY, Y = Year
WW, W = Work Week
G
= Pb−Free Package
ORDERING INFORMATION
Device
Package Shipping^†
CS51221ED16
SOIC−16 48 Units / Rail
CS51221ED16G
CS51221EDR16
SOIC−16 48 Units / Rail
(Pb−Free)
SOIC−16 2500 Tape & Reel
CS51221EDR16G
CS51221EDTB16G
SOIC−16 2500 Tape & Reel
(Pb−Free)
TSSOP−16 96 Units / Rail
(Pb−Free)
CS51221EDTB16R2G TSSOP−16 2500 Tape & Reel
(Pb−Free)
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specifications
Brochure, BRD8011/D.
Publication Order Number:
CS51221/D