The design for the PHD450, 450W ac-dc power supply is being offered for no charge by Oltronics Inc. to qualified partner companies. This 3-inch by 5-inch digitally-controlled power supply design includes a microcontroller with a sophisticated embedded digital control algorithm.
The PHD450 design includes active PFC and universal input, and features a minimum efficiency of over 91% for 110Vin and 94% for 220Vin. Airflow of 10cfm is required for the nominal power of 450W. With natural convection cooling, the unit is rated for 300W at 25°C and 250W at 50°C, both with an input voltage of 90Vac.
The design also includes digital load sharing over a CAN bus, and programmable over-voltage, over-power and short circuit protections. All electrical parameters, timing and behavior can be accessed and modified over an I2C bus using PMBus™ commands or an RS-232 bus.
The digital control algorithm includes self-diagnostic and auto-optimization capabilities. The algorithm automatically adjusts the control loop parameters, so that the temperature excursion on components throughout the PCB is held at a minimum, thus reducing the occurrence of hot spots and enhancing reliability.
These units include a 12V, 1A output to power an optional cooling fan. Embedded active OR-ing is included for N+1 redundant operation. Hold-up time is 22ms at an output of 450W.
The design is covered by two US patents.
