Supply chain management: a 2001 lesson
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COSTA MESA, CALIF.- BroadBand TelCom Power claims to have set new power-density standards in dc/dc converters, squeezing 960 watts into a package not much larger than a full brick (4.6 x 2.5 x 0.5 inches) with the use of its single-turn flat transformer technology.
Delivering up to 185 amps and with basic dimensions of 6.5 x 2.5 x 0.5 inches, the converter is designed as an alternative to multiple-unit power supplies in high-current applica- tions. It's also the first device packaged in the company's MiniPack Series of card cages.
"One problem with multiple units running near maximum and with current-sharing schemes is rapid system shutdown if there's a fault," said James Lau, president of BTC Power. "We believe one high-reliability brick is superior to the traditional approach."
The 960-W units are available separately or in a card cage (approximately 13 x 3 x 0.5 inches) that includes a replaceable fuse to guard against input surges and a common-mode filter to reduce conducted input ripple noise and to help reject both power-line surge and fast dv/dt. The dc/dc converter delivers up to 1 kW at 3 to 24 volts from a nominal 300-V input (split 160-V plus and minus sources). Output characteristics include a line and load regulation of 1 percent, transient response (settling time) of 180 microseconds, and overshoot and undershoot of plus/minus 200 mV for a 25 to 75 percent load change.
Input-to-output, input-to-base, and output-to-base isolation is 3,750, 2,500 and 500 V, respectively. Protection features include circuitry for short-circuits (automatic recovery), output overvoltage and overcurrent, and baseplate overtemperature. Typical converter efficiency at full load is 80 percent over an operating temperature range of -10 degrees C to 55 degrees C.
The heat-generating devices in the version that comes in the MiniPack include eight current-sharing dual output diodes-a total of 16, with each carrying an average of 12 A. These and the other heat-generating devices, such as ferrite and transformer windings, are distributed and bonded to an aluminum baseplate to reduce diode junction temperature to less than 10 degrees C above the baseplate temperature. Calculated mean time between failures is nearly 500,000 hours.
The 960-W dc/dc converter is priced at about $350, with the converter in the MiniPack priced at $500. Bulk discounts are available.
CALL (714) 850-7320
www.btcpower.com
EETInfo No. 625