1. Features (see Fig. 1 for outside view, and Table 1 for models) Range of input DC voltage: 18~36V, nominal input DC voltage 28V Output power: 20W Operating temperature (Tc): -55~+105℃ Input, output and case are isolated mutually Insulation resistance: R≥100MΩ (DC 500V) With the function of inhibit and short-circuit protection Power density: 28W/in3 Totally sealed metal case 2. Scope of application High-reliability electronic system for aviation and aerospace, etc. 3. Description HHW28 series high-reliability DC/DC converter can work at 28V input voltage, and the output power is 20W.The case of this series is of totally sealed metal structure with fixed end or without fixed end. HTW28 series products adopt PWM push-pull technology, and the constant switching frequency is 200~300kHz. The design and manufacture of HHW28 series products meet the requirements of GJB2438A-2002 “General specification for hybrid integrated circuit”, and the test method and procedure for electric circuit executes GJB548A-96 "Test methods and procedures for microelectronics".