This reference design is a full-bridge topology that is comprised of a TPS7H5005-SEP referenced on secondary ground that controls three TPS7H6005-SEP half-bridge gate drivers. The two drivers referenced to the primary side operate in PWM mode which allows for the design to achieve zero-voltage switching (ZVS) at higher loading conditions. On the secondary side the other driver controls a pair of secondary rectifiers to further improve the conversion efficiency. In this design the controller, half-bridge drivers and GaN field-effect transistors (FET) are chosen to meet radiation for geostationary orbit (GEO). These components can be swapped out to meet other mission specifications.

• GEO class radiation performance
• GaN FETs on primary and secondary side to increase efficiency
• Secondary-side controller for faster control loop
• < 1% voltage ripple on output
• Single-side assembly, two-layer, 3.25 in × 5.5 in PCB

• Command and data handling (C and DH)
• Optical imaging payload
• Radar imaging payload

Top of Board

Angled Image

Bottom of Board

• Unless noted, all tests were conducted with 25A loading on the output
• Local airflow used
• External 12V bias applied to primary and secondary sides

Air flow is recommended to test at full load conditions. Thermal image shows relative temperature rise across the PCBA.

Figure 1-1 Test Setup