Product Overview NCP1377: Controller, Free Running Quasi-Resonant Current Mode For complete documentation, see the data sheet Product Description The NCP1377 combines a true current mode modulator and a demagnetization detector which ensures full borderline / critical Conduction Mode in any load/line conditions together with minimum drain voltage switching (Quasi-Resonant operation). Due to its inherent skip cycle capability, the controller enters burst mode as soon as the power demand falls below a predetermined level. As this happens at low peak current, no audible noise can be heard. For NCP1377, an internal 8.0µs timer prevents the free-run frequency to exceed the 150kHz CISPR-22 EMI starting limit while the skip adjustment capability lets the user select the frequency at which the burst foldback takes place. For NCP1377B, the internal timer duration is reduced to 3.0µs to allow operation at higher frequencies. The transformer core reset detection is done through an auxiliary winding which, brought via a dedicated pin, also enables fast OverVoltage Protection (OVP). Once an OVP has been detected, the IC permanently latches-off. The 1377 features a sampling time of 4.5µs whereas it is 1.5µs for the B version. The NCP1377 also features an efficient protective circuitries which, in presence of an overcurrent condition, disables the output pulses and enters a safe burst mode, trying to re-start. Once the default has gone, the device auto-recovers. Finally an internal 1ms soft-start eliminates the traditional startup stress. Features • • • • • • • • • • Free-running borderline / critical mode quasi-resonant operation Latched Over Voltage Protection Auto-recovery short-circuit protection via UVLO crossover External latch triggering, e.g. via over-temperature signal Current-Mode with adjustable Skip-cycle capability Internal 1ms soft-start Internal temperature shutdown Internal Leading Edge Blanking 500mA peak current source/sink capability Under Voltage Lockout level of 12.5V (on) and 7.5V (min) For more features, see the data sheet Applications • • • • AC/DC adapters for notebooks etc. Offline battery chargers Consumer electronics (DVD players, set-top boxes, TVs, etc.) Auxiliary power supplies (USB, appliances, TVs etc.) 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 NCP1377BD1R2G Pb-free Active Flyback Current Mode Variable Yes Yes No Yes Yes 16 500 / 500 SOIC-7 Active Flyback Current Mode Variable Yes Yes No Yes Yes 16 500 / 500 SOIC-8 Active Flyback Current Mode Variable Yes Yes No Yes Yes 16 500 / 500 PDIP-8 Active Flyback Current Mode Variable Yes Yes No Yes Yes 16 500 / 500 SOIC-7 Active Flyback Current Mode Variable Yes Yes No Yes Yes 16 500 / 500 SOIC-8 Active Flyback Current Mode Variable Yes Yes No Yes Yes 16 500 / 500 PDIP-8 Halide free NCP1377BDR2G Pb-free Halide free NCP1377BPG Pb-free Halide free NCP1377D1R2G Pb-free Halide free NCP1377DR2G Pb-free Halide free NCP1377PG Pb-free Halide free Application Diagram For more information please contact your local sales support at www.onsemi.com Created on: 6/30/2016