The eGaN IC-based reference design addresses new USB PD 3.1 stringent demands for multi-port chargers and on-motherboard DC/DC converting a 28 to 48V input to 12 or 20V output.

The EPC9177 digitally-controlled, single output synchronous buck converter reference design board operates at 720kHz switching frequency, converting an input voltage of 48, 36 or 28V to a regulated 12V output voltage and delivering up to 20A continuous output current.

The compact synchronous buck converter measures 21 x 13mm and a low profile of 3.0mm. It features the EPC23102 integrated half-bridge ePower stage and is optimised for computing power supplies and USB PD 3.1 multi-port chargers and on-board DC/DC.

In USB PD 3.1 applications, the output voltage for USB charging increases from 20 to 48V and power increases from 100 to 240W. This higher power enables USB charging beyond laptop and cell phone fast charging to higher power applications including gaming PCs, power tools and e-bikes. The main output of chargers is 48V to allow the higher output power with 5.0A rated cables, but multi-port chargers can also support lower output voltages (e.g. 5.0, 12 and 20V) to be compatible with a wider range of devices. A smart DC/DC regulator is required to generate these lower voltages and a DC/DC regulator is required on the end product’s motherboard to convert the input voltage.

The EPC23102 GaN power stage integrates the half bridge driver and FETs (100V, 6.6 mΩ RDSon, the level shifter and the bootstrap charging and can switch with very high efficiency up to 3MHz. It enables the EPC9177 reference board to deliver up to 20A continuous current using a heatsink and 15A continuous current without a heatsink to 12V output voltage, with greater than 97.3% efficiency with a 48 V input.

The reference design is suitable for high power applications including computing, industrial, consumer and telecomms power systems which require high efficiency but a small size. eGaN FETs and ICs provide the fast switching, high efficiency and small size that can meet the stringent power density requirements of these leading-edge applications, says EPC.

The EPC9177 reference design board is available from EPC and available for immediate delivery from Digi-Key.