NCP1654BD65R2G

The main function of the NCP1654 controller described in the document is to operate as a Power Factor Correction (PFC) driver in fixed frequency, continuous conduction mode. It is designed to ensure high power factor, reliability, and cost-effectiveness in systems where these parameters are crucial .

The NCP1654 controller minimizes the use of external components by requiring a minimum of external components in its design. Specifically, it is housed in a SO8 package and simplifies the PFC stage design, eliminating the need for any input voltage sensing. This helps in reducing the complexity of the circuit scheme and streamlining the overall design process.

The NCP1654 PFC controller has several safety features integrated into its design. These include: 1. Permanent monitoring of the output voltage, coil current, and die temperature to protect the system from over-stresses . 2. Integrated protections such as overvoltage protection, coil current limitation, and thermal shutdown to make the PFC stage robust and reliable . 3. Maximum current limit feature that senses the coil current and immediately turns off the power switch if it exceeds the set current limit, protecting the MOSFET from excessive stress . 4. Undervoltage protection for open-loop protection or shutdown, detecting when the circuit is in an undervoltage condition . 5. Over-power limitation that computes the maximum permissible current based on the average input voltage and resets the driver output if excessive power transfer is detected . 6. Thermal shutdown feature that disables the circuit gate drive and keeps the power switch off when the junction temperature exceeds 150°C, with operation resuming once the temperature drops below about 120°C . These safety features ensure the protection and reliability of the NCP1654 PFC controller in various operating conditions.