To help reduce design time, size, and cost for applications in high-temperature, high-shock environments—particularly oil drilling and mud turbine generators—engineers may want to consider the HTH27022S and HTM27092S isolated hybrid hermetic dc-dc converters. The devices, developed by International Rectifier, feature an operating case temperature of 165°C with transient up to 175°C. Nominal input voltage is 270 V. Output power for the 27022S and 27092S is 55 W (22 V at 2.5 A) and 92 W (92 V at 1.0 A), respectively. They incorporate an internal electromagnetic-interference (EMI) filter and magnetically coupled current feedback. Protection includes undervoltage lockout, output overvoltage limiter, external inhibit, short circuit, and overload. Dimensions for the HTH27022S and HTM27092S are 3.5 by 2.15 by 0.4 in. and 4.0 by 2.15 by 0.4 in., respectively.