90W Boost PFC + Half Bridge LLC + SR AC-DC Reference Design
The EV44010-S+HR1000-S-01B evaluation board from Monolithic Power Systems provides a reference design for a 90W ac-dc adapter. The board is designed in a very small form factor with a very high power density.
With an input voltage range of 90- to 265-Vac and a 19.2Vdc/4.7A output, this design is suitable for use as a high-end portable computer power adapter. The particular benefits for the board are the very low no-load power consumption (<0.5W) and the very high overall efficiency.
The EV44010-S+HR1000-S-01B is based on two-stage approach: the front stage is a boost PFC pre-regulator using MP44010; the second stage is a half bridge resonant converter with synchronous rectifier using HR1000 and MP6922.
The MP44010 is a boundary conduction mode PFC controller which can provide simple and high-performance active power factor correction using minimum external components.
The HR1000 is a controller designed specifically for the resonant half-bridge ZVS. It controls the output power by changing the switching frequency and controlling the half-bridge with a constant 50% duty cycle. And HR1000 can optimize the light load consumption for the burst mode operation.
EV44010-S+HR1000-S-01B schematic (click on schematic to enlarge)
Summary of features:
- Ultra Small Form Factor (L x W x H - 88.5mm x 57mm x 14mm)
- High Power Density
- Active PFC and Maximum Efficiency up to 92.5%
- No Load Power Consumption Less than 0.5W
- Meet EN55022 Class B Standard
- Meet IEC61000-3-2 Class D Standard
- Output Short Circuit Protection
- Over Voltage Protection
