Product Overview

Product Overview
NCP1253: PWM Controller, Current Mode, for Offline Power Supplies
For complete documentation, see the data sheet
Product Description
The NCP1253 is a highly integrated PWM controller capable of delivering a rugged and high performance offline power supply in a
tiny TSOP-6 package. With a supply range up to 28 V, the controller hosts a jittered 65 kHz or 100 kHz switching circuitry operated
in peak current mode control. When the power on the secondary side starts to decrease, the controller automatically folds back it's
switching frequency down to a minimum level of 26 kHz. As the power further goes down, the part enters skip cycle while limiting the
peak current. To avoid sub harmonic oscillations in CCM operation, adjustable slope compensation is available via the series
inclusion of a simple resistor in the current sense signal. Besides the auto-recovery timer-based short-circuit protection, an Over
Voltage Protection on the Vcc pin protects the whole circuitry in case of optocoupler destruction or adverse open loop operation.
Features
Benefits
• Frequency Foldback down to 26 kHz and Skip-Cycle in Light
Load
• Internal Ramp Compensation
• Frequency Jittering in Normal and Frequency Foldback
modes
• Over Voltage Protection (OVP) monitoring on the Vcc pin
• Timer-based Auto-Recovery or Latched Short-Circuit
Protection
Applications
• Improved efficiency across the load range
• Reduces the number of external components
• Low EMI signature
• Protects against output over voltage conditions without any
added components
• Protection against fault conditions
End Products
• Offline Adapters
• AC-DC converters
• Set-top Boxes
• Printers
• Notebooks and Netbooks
Part Electrical Specifications
Product
Compliance
Status
Topolog
y
Control
Mode
fsw Typ
(kHz)
StandUVLO
by Mode (V)
Short
Circuit
Protecti
on
Latch
Soft
Start
VCC Max Drive
(V)
Cap.
(mA)
Packag
e Type
NCP1253ASN100T1G
Pb-free
Active
Flyback
Current
Mode
100
Yes
8.8
Yes
Yes
Yes
28
300 /
500
TSOP-6
Active
Flyback
Current
Mode
65
Yes
8.8
Yes
Yes
Yes
28
300 /
500
TSOP-6
Active
Flyback
Current
Mode
100
Yes
8.8
Yes
No
Yes
28
300 /
500
TSOP-6
Active
Flyback
Current
Mode
65
Yes
8.8
Yes
No
Yes
28
300 /
500
TSOP-6
Halide free
NCP1253ASN65T1G
Pb-free
Halide free
NCP1253BSN100T1G
Pb-free
Halide free
NCP1253BSN65T1G
Pb-free
Halide free
For more information please contact your local sales support at www.onsemi.com
Created on: 6/30/2016