MAX1970/MAX1971/MAX1972 ultra-compact, dual step-down DC-DC

Source: Maxim Integrated Products

Maxim Integrated Products introduces the MAX1970/MAX1971/MAX1972 ultra-compact, dual step-down DC-DC converters, which are the smallest power supplies for gigabit interface card (GBIC) modules and USB-powered xDSL modems and routers. They integrate the power MOSFETs and operate at 1.4MHz and 180 degrees out-of-phase to reduce component sizes (less than 1.8mm high). They also integrate necessary monitoring functions such as power-on reset (POR) and power-fail detection for USB-powered devices. All three devices operate from a 2.6V to 5.5V supply and deliver 750mA at each output.

The MAX1971 is optimized for GBIC and small-form-factor module applications. Its 700kHz switching frequency minimizes inductor and capacitor size. POR, with a reset input function and integrated power switches, minimizes package count and size. Its 180 degrees out-of-phase operation reduces the input bypass capacitor to 10 microfarads and minimizes inrush current at power-up. The 1% accurate output allows accurate voltage setting to minimize power consumption.

The MAX1970/MAX1972 operate at 1.4MHz to eliminate interference with the ADSL band and improve the data rate. Their 10mF input capacitor complies with USB requirements. A USB power-fail detector (for "dying-gasp" applications) is integrated to allow orderly shutdown when power is removed. Integrated power switches and small external components reduce solution cost.

For telecom and networking equipment, these devices eliminate two LDOs and reduce heat when operated from a 3.3V or 5V input bus.

These devices are specified for the extended-industrial temperature range (-40 degrees Celsius to +85 degrees Celsius) and come in 16-pin QSOP packages (same size as 8-pin SO). The MAX1970EEE/MAX1971EEE start at $2.50 and the MAX1972EEE starts at $3.50 (1000-up, FOB USA). The MAX1970 evaluation kit is available to speed designs.

Maxim Integrated Products, 7250 N.W. Evergreen Pkwy, Hillsboro, OR 97124. Tel: 503-547-2016; Fax: 503-547-0142.