NCP1251CSN65T1G Datasheet PDF - ON Semiconductor

The NCP1251CSN65T1G is a current-mode Pulse Width Modulation (PWM) Controller for off-line power supplies. It is capable of delivering a rugged and high performance offline power supply. With a supply range up to 28V, the controller hosts a jittered 65 or 100kHz switching circuitry operated in peak current-mode control. When the power on the secondary side starts to decrease, the controller automatically folds back its switching frequency down to a minimum level of 26kHz. As the power further goes down, the part enters skip cycle while limiting the peak current. Over power protection (OPP) is a difficult exercise especially when no-load standby requirements drive the converter specifications. The ON proprietary integrated OPP lets you harness the maximum delivered power without affecting your standby performance simply via two external resistors. A latched Over Voltage Protection (OVP) is combined on the same pin. For ease of implementation, a latched OVP also monitors the VCC line.

● Internal ramp compensation

● Internal fixed 4ms soft-start

● 100ms Timer-based auto-recovery short-circuit protection

● Frequency jittering in normal and frequency foldback modes

● Option for auto-recovery or latched short-circuit protection

● OVP Input for improved robustness

● Latched OVP protection on VCC

● Less than 100mW Standby power at high line

● EPS 2.0 Compliant