CS2842A Datasheet, PDF (1/10 Pages) Cherry Semiconductor Corporation – Off-Line Current Mode PWM Control Circuit with Undervoltage Lockout

CS2842A, CS3842A,
CS2843A, CS3843A
Off−Line Current Mode
PWM Control Circuit with
Undervoltage Lockout
The CS284XA, CS384XA provides all the necessary features to
implement off−line fixed frequency current−mode control with a
minimum number of external components.
The CS384XA family incorporates a new precision
temperature−controlled oscillator with an internally trimmed
discharge current to minimize variations in frequency. A precision
duty−cycle clamp eliminates the need for an external oscillator when a
50% duty−cycle is used. Duty−cycles greater than 50% are also
possible. On board logic ensures that V_REF is stabilized before the
output stage is enabled. Ion implant resistors provide tighter control of
undervoltage lockout.
Other features include low startup current, pulse−by−pulse current
limiting, and a high−current totem pole output for driving capacitive
loads, such as the gate of power MOSFET. The output is LOW in the
off state, consistent with N−channel devices.
The CS384XA series of current−mode control ICs are available in
8 and14 lead packages for surface mount (SO) applications as well as
8 lead PDIP packages.
Features
• Optimized for Off−line Control
• Internally Trimmed Temperature Compensated Oscillator
• Maximum Duty−Cycle Clamp
• V_REF Stabilized Before Output Stage is Enabled
• Low Startup Current
• Pulse−By−Pulse Current Limiting
• Improved Undervoltage Lockout
• Double Pulse Suppression
• 1.0% Trimmed Bandgap Reference
• High Current Totem Pole Output
http://onsemi.com
MARKING
DIAGRAM
8
8
1
8
1
DIP−8
N SUFFIX
CASE 626
SO−8
D SUFFIX
CASE 751
x84yA
AWL
YYWW
1
8
x84yA
ALYWX
14
1
SO−14
D SUFFIX
CASE 751A
1
14
CSx84yA
AWLYWW
1
x
= 2 or 3
y
= 2 or 3
A
= Assembly Location
WL, L = Wafer Lot
YY, Y = Year
WW, W = Work Week
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 8 of this data sheet.
© Semiconductor Components Industries, LLC, 2006
1
July, 2006 − Rev. 4
Publication Order Number:
CS2842A/D