EmbeddedRelated.com
    Parts    NCP1252ADR2G
NCP1252ADR2G

ONNCP1252ADR2G

onsemi
Converter Offline Flyback, Forward Topology Up to 500kHz 8-SOIC
Active1,744 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The NCP1252ADR2G is a high-performance current-mode PWM controller designed for offline and DC-DC power supply applications including flyback and forward topologies. It features an adjustable switching frequency up to 500 kHz and incorporates frequency jittering to simplify EMI filter design. The device is specifically tailored for designs requiring a maximum 50 percent duty cycle and robust protection mechanisms.

Why Choose This Part

This controller provides a 10V typical start-up voltage and supports peak current mode control for excellent line and load transient response. It offers a programmable soft-start, internal ramp compensation for stability, and a dedicated 10 ms latched primary overcurrent protection timer. The high drive capability of +500/-800 mA allows it to directly drive external power MOSFETs efficiently.

Applications

AC-DC Adapters
Ideal for building high-efficiency offline power converters for consumer and industrial electronics.
ATX Power Supplies
Utilized in auxiliary power stages and main converters where forward topology and precise duty cycle control are required.
Telecom Power Modules
Suitable for isolated DC-DC converters in telecommunications infrastructure due to its wide 28V VDD range and high-frequency capability.

Key Specifications

Topology Flyback, Forward
Duty Cycle 48%
Mounting Type Surface Mount
Package / Case 8-SOIC (0.154", 3.90mm Width)
Control Features Frequency Control, Soft Start
Fault Protection Current Limiting
Output Isolation Isolated
Internal Switch(s) No
Voltage - Start Up 10 V
Frequency - Switching Up to 500kHz
Operating Temperature -25degC ~ 125degC (TJ)
Supplier Device Package 8-SOIC
Voltage - Supply (Vcc/Vdd) 9V ~ 28V

Getting Started

To begin design, select the switching frequency by choosing the timing resistor for the RT pin and calculate the soft-start capacitor based on the desired power-up ramp. Use the internal ramp compensation to prevent sub-harmonic oscillations when operating near the 50 percent duty cycle limit. Evaluation can be performed using standard SOIC-8 prototyping boards or by following the reference designs for forward and flyback converters provided by onsemi.