AHV2812D

HYBRID-HIGH RELIABILITY DC-DC CONVERTER PD-94583C AHV28XX SERIES 28V Input, Single, Dual and Triple Output Description The AHV Series of DC-DC converters are designed to replace the AHE/ATO family of converters in applications requiring compliance to MIL-STD-704A through E, in particular the input surge requirement of 80V specified to withstand transient input voltage of 80V. No input voltage or output power derating is necessary over the full military temperature range. These converters are packaged in an extremely rugged, low profile package that meets all requirements of MILSTD-883 and MIL-PRF-38534. Parallel seam weld sealing and the use of ceramic pin feed thru seals assure long term hermeticity after exposure to extended temperature cycling. The basic circuit is a push-pull forward topology using power MOSFET switches. The nominal switching frequency is 500kHz. A unique current injection circuit assures current balancing in the power switches. All AHV series converters use a single stage LC input filter to attenuate input ripple current. A low power 11.5V series regulator provides power to an epitaxial CMOS custom pulse width modulator integrated circuit. This single integrated circuit provides all PWM primary circuit functions. Power is transferred from primary to secondary through a ferrite core power transformer. An error voltage signal is generated by comparing a highly stable reference voltage with the converter output voltage and drives the PWM through a unique ...