This reference design is a 28-V output, 5-A
synchronous buck converter for space applications operating from a 50-V to 150-V input
range. The TPS7H5001-SP PWM controller controls the power stage. The INA901-SP senses
the inductor current and provides current feedback to the controller enabling both
average current-mode control and output short-circuit protection. If these features are
not needed, the INA901-SP can be removed and the TPS7H5001-SP can be operated with
voltage-mode control. The adjustable dead time of the TPS7H5001-SP allows the timing of
the switching MOSFETs to be optimized and results in over 94% efficiency with a 100-V
input and over 96% efficiency with a 50-V input. A self-biasing circuit is included to
power the control circuits directly from the output. If an external 12-V bias is
provided, the self-biasing circuit can be removed, and results in higher
efficiency.