The APM32F407 communication power solution prioritizes stability to ensure optimal speed, accuracy, and smoothness. With a single MCU, it provides full digital control of the PFC and LLC units, enabling zero-voltage switching across the entire load range and improving efficiency and reliability.

Based on the high-performance APM32F407 MCU, this solution features a digitally controlled compact isolated AC/DC power supply with two main power units: a boost-type PFC unit at the front end and a resonant LLC full-bridge isolated DC/DC converter unit at the back end. This setup allows for PWM generation for power electronic switching devices in all operating modes, including waveform, variable duty cycle, variable switching frequency, and phase shift control.

APM32F407 Communication Power Solution Block Diagram

APM32F407 Communication Power Solution Working Process

The solution's ADC module acquires the digital signals of AC input voltage Vac-LN, current Ig, and the bus voltage Vdc of the PFC unit, as well as the isolated sampling of output voltage Vout and current Iout of the LLC stage.

With the powerful floating-point computing capability of the APM32F407, the loop calculation and logic control functions of the PFC and LLC units can be achieved in a single sampling cycle.

The output of the loop calculation is then fed to the advanced timer module of APM32F407, which produces a PWM waveform with a fixed switching frequency and variable duty cycle for the PFC unit and a PWM waveform with a fixed duty cycle and variable switching frequency for the LLC unit. This results in improved power factor and voltage boosting for the PFC unit and stabilization of the output voltage and ability to respond to load transients for the LLC unit.

APM32F407 Communication Power Solution Advantages

•  32-bit Arm® Cortex®-M4F core with a maximum frequency of 168MHz, supporting loop control of PFC and LLC.

•  Built-in three 12-bit ADCs, each with up to 16 external channels. Supports DMA and meets the PFC+LLC communication power supply 3-channel voltage and 3-channel current acquisition requirements.

•  Two 16-bit advanced timers TMR1 and TMR8 can provide 7-channel PWM output. Supports dead band generation and brake input.

•  Four USART and Two UART communication interfaces meet the interaction needs of the power supply and upper-layer systems.

•  1MB Flash and 192KB+4KB SRAM meet program storage and computing requirements, and redundancy to facilitate program expansion.

•  Built-in backup registers for flexible storage of control parameters without external EEPROM.

•  Supports AC 90V~AC264V, frequency 50/60Hz, full grid compatibility.

The APM32F407 communication power solution is equipped with real-time monitoring and fast protection features for rectifier input voltage and current, RMS input voltage and current, bus voltage power supply, and output voltage and current. This makes it well-suited for use in various scenarios such as commercial networks, servers, industrial AC/DC power supplies, new energy, and power storage.