2 PCB Hardware Modifications for 60-V Tolerance

Figure 2-1 shows the schematics for TPS272C45C suited for 60-V tolerance with the modifications to standard EVM highlighted in the red boxes. Figure 2-2 shows a simplified diagram for the schematics with the optional components highlighted in the green boxes. For 60-V tolerance, the C version of the TPS272C45 should be used as it allows the use of an external VDS clamp for higher voltage across the device. There are several 60-V TVS diodes populated on the modified board. D4 between VS and GND absorbs most of the energy when the surge comes in. D10 and D12 both ensure the voltage across the part does not exceed 60 V. Optionally, the TVS and Schottky diode D2 and D8 at the output can be populated to replace D10 for VDS clamping during the inductive load discharge. Do note, other passive components in the circuit such as capacitors also need to be rated above 60 V to survive the high voltage without damage.