ON Semiconductor NCP1200 Manuals

The NCP1200 is a PWM current-mode controller for low-power universal off-line supplies from Semiconductor Components Industries, LLC. It is housed in SOIC-8 or PDIP-8 packages, and features a small size, low power consumption, and low noise.

The NCP1200 is a PWM current-mode controller for low-power universal off-line supplies. It is housed in an SOIC-8 or PDIP-8 package, representing a major leap toward ultra-compact switchmode power supplies. The circuit allows the implementation of a complete offline battery charger or a standby SMPS with few external components due to a novel concept. Furthermore, an integrated output short-circuit protection allows the designer to build an extremely low-cost AC-DC wall adapter associated with a simplified feedback scheme. The controller drives low gate-charge switching devices like an IGBT or a MOSFET, requiring very small operating power. Due to current-mode control, the NCP1200 simplifies the design of reliable and cheap offline converters with extremely low acoustic generation and inherent pulse-by-pulse control. When the current setpoint falls below a given value, e.g. the output power demand diminishes, the IC automatically enters the skip cycle mode and provides excellent efficiency at light loads. This occurs at low peak current, so no acoustic noise takes place. Finally, the IC is self-supplied from the DC rail, eliminating the need for an auxiliary winding. This feature ensures operation in the presence of low output voltage or shorts.

The NCP1200 is a PWM current-mode controller designed for low-power universal off-line supplies. It allows the implementation of a complete offline battery charger or a standby SMPS with few external components due to its novel concept. The integrated output short-circuit protection enables the designer to build an extremely low-cost AC-DC wall adapter with a simplified feedback scheme. The controller operates at a fixed frequency of 40 kHz, 60 kHz, or 100 kHz and drives low gate-charge switching devices like an IGBT or a MOSFET, requiring very small operating power. The NCP1200 simplifies the design of reliable and cheap offline converters with low acoustic generation and pulse-by-pulse control thanks to its current-mode control. When the current setpoint falls below a certain value, such as when the output power demand decreases, the IC automatically enters the skip cycle mode, providing excellent efficiency at light loads. This occurs at low peak current, resulting in no acoustic noise. The IC is self-supplied from the DC rail, eliminating the need for an auxiliary winding and ensuring operation even in the presence of low output voltage or shorts.