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