MIL-STD-1275E standard provides the latest characteristics for 28-V DC input power for using equipment in military vehicles. The standard characterizes three main events that occur during operation of a military vehicle, and any equipment connected to the 28-V main power supply must be protected against these three events. These events are reverse polarity, voltage spike and voltage surge. To pass these events, do not operate the protection circuit during a reverse polarity event. The output of the protection circuit should be nominal 28 V and maximum at 34 V throughout the duration of the spike and surge events. This reference design features a two-stage clamping circuit that can handle a maximum of 120-W output. By implementing a two-stage clamping circuit, the design helps reduce the overall cost of the bill of materials (BOM) and minimize the overall size.
Features
- Two-stage 100-V surge suppression
- 250-V spike surge suppression
- Reverse-input protection to -65 V