45W Open Source GaN Charger

 The chip solution uses DK045G+DK5V120R15V+FS8626+NDP13401KC.
 
 
 Aging data under ambient temperature (30°C): Input AC115V 60HZ, Output 20V 2.25A:
   I-shaped inductor: 90℃;
   DK045G GaN chip: 75
   ℃; Rectifier bridge
   : 77℃; RCD absorption
   diode: 81℃; Synchronous rectifier
   chip: 70℃;
   Transformer coil: 75℃; Transformer core
   : 69℃; Buck chip: maximum
   79℃; Buck inductor: maximum 70℃.
Ripple measured with a load tester:
Output voltage ripple: 20V/2.25A: 62mV, 15V/3A: 36mV, 12V/3A: 36mV, 9V/3A: 36mV, 5V/3A: 34mV. A screenshot of the ripple test is shown.
Ripple is measured at its maximum value under different input voltages. Conversion efficiency is measured under the following conditions: input 230VAC, 50Hz.
Supported protocols: PD3.0, DCP. See the diagram for specific supported PDO levels. Both ports support 45W fast charging. Power allocation for simultaneous dual-port insertion is C1: 27W, C2: 18W.
The FS8626 protocol chip can also support more charging protocols, such as SCP, FCP, QC, etc. These charging protocols are not enabled internally in this design. If you need to support these protocols, connect the D+ and D- terminals of the FS8626 on PCB2 to the D+ and D- terminals of the USB-C female connector via traces and enable these protocols in the protocol chip.
With an input of 264VAC and a full-load output of 20V, the highest peak voltage spike of the gallium nitride (GaN) switch was 544V
upon power-on/off. With an input of 264VAC and a full-load output of 20V, the highest peak voltage spike of the synchronous rectification was 108.5V upon
power-on/off. With an input of 115VAC at 60Hz and a full-load output of 20V, the voltage between the GaN and diodes (DS) before power-on was only around 40V, essentially achieving zero-voltage switching (ZVS), with very low switching losses.
EMI radiation test data showed a pass with a 4dB margin.