Calex Presents HEW Series Half-Brick DC-DC Converters

Calex Manufacturing Co. Inc. (Concord, CA) presented its the HEW Series of 100 W single-output, half-brick dc-dc converters, which offer an ultra-wide input range of 9 Vdc to 36 Vdc and 18 Vdc to 75 Vdc. Output voltages of 3.3 Vdc, 5 Vdc, 12 Vdc, 15 Vdc and 24 Vdc are available. The input range allows operation from 12 V battery, 24 V industrial bus power and 48 V telecom sources.

The switching frequency of the 100 W HEW Series is 325 kHz. Efficiencies, even with the wide input range, run as high as 88%. The units feature under-voltage lockout and input reverse-voltage protection. Turn-on overshoot with the HEW Series is non-existent and shown on the data sheet as 0%. Output noise is as low as 20 mV RMS. Line and Load regulation is 0.01% and 0.02%, respectively. Short-circuit protection is provided by pulse-by-pulse current limiting with frequency foldback and dead-short shutdown. Input-to-output isolation is 1,544 Vdc for 48 V nominal input models and 700 Vdc for 24 V nominal input models.

Other features include on/off, remote sense and trim. The "off" idle current is only 2 mAdc. The trim range is specified at ±10%. Line regulation under remote sensing is 0.02% and load regulation under remote sensing is 0.05%. The half-brick case size measures 2.28 in x 2.4 in x 0.55 in. The unit offers an aluminum baseplate for improved thermal performance and is potted, making the HEW suitable for still-air or limited airflow applications. The baseplate operating temperature is from -40 °C to +100 °C. The HEW features thermal shutdown. UL60950 and EN60950 approvals are pending.

Pricing is $55 in OEM quantities. Units are available from stock.