Surge stopper solution is MIL-STD-1275D compliant

When faced with the stringent surge, spike and ripple waveforms specified in MIL-STD-1275D, the DC2150A limits the output voltage to a safe 44V. For most applications, satisfying the standard is as simple as placing the DC2150A circuit in front of a 44V tolerant device. It employs surge stopper ICs LTC4366 and LT4363, controlling series N-channel MOSFETs, reducing the solution size and cost compared to traditional shunt circuits utilising bulky capacitors, fuses, inductors and transient voltage suppressors.

The DC2150A is designed to withstand input transients up to ±250V and to provide a minimum of 4A current to the load in all conditions except the ±7V ripple condition when the available current is reduced to 2.8A. The N-channel MOSFETs are protected against output overloads by current limiting. Sustained overvoltage or overcurrent conditions turn off the circuit after a timer delay; the circuit turns on automatically after a cooldown cycle. Thermal protection circuitry turns off the LT4363 controlled MOSFET when its temperature exceeds 105°C.

The DC2150A has four assembly options (DC2150A-A through DC2150A-D), depending on maximum load current and the ability to ride through the 500ms long 100V peak surge. BOM costs are reduced on the board options which eliminate unneeded protection features. Only the full-featured option, DC2150A-C, is available now, priced at $150.00 each.