1/4-brick DC/DC converters in the InQor IQ72 series from SynQor use synchronous rectification to achieve power-conversion efficiencies of up to 91% at full load. The ruggedised, board-mountable, isolated, fixed-switching-frequency industrial DC/DC converters are supplied encased to provide protection from harsh environments. The 42 to110V inputvoltage range and the selection of output voltages and power levels make the modules suitable for 72V systems, such as industrial-automation and railway electronics. The robust modules have an operating-temperature range of -40 to +100°C. The 1/4-brick format is comprised of nine output voltages: 1.8, 3.3, 5, 7, 12, 15, 24, 30, and 48V. Two converters of different power levels are available for each output voltage for a total of 18 models. These converters provide output-power ratings ranging from 58 to 150W. The modules addresse many of the UK BRB/RIA12 and French NFF 01-510 railway standards and the EU EN50155 standard requirements for Railways Applications Electronic Equipment Used on Rolling Stock for 72V batteries with no voltage stabilisation. The series also meets the three main electrical requirements of permanent input voltage, 100ms brownout and 1s transient. The use of fixed-switching-frequency technology provides predictable EMI performance, which greatly simplifies filtering design. Features include on/off control referenced to the input side, remote sense for the output voltage, and an output-voltage trim range from -20 to +10%. Protection features include input-undervoltage-lockout, output-current-limit and short-circuit protection, active back bias limit, output over-voltage protection and thermal shutdown. All models have a reinforced input-to-output isolation of at least 3000V DC and 100MOhm. MTBF is in excess of 2Mh, and the modules are RoHS-compliant.
