The operating voltage range is 2.4 V to 5.5 V and the maximum output current is 127-mA. Allegro's A3904 internal protection features include thermal shutdown and under voltage lockout. Logic input levels are independent of the supply voltage and the operating temperature range is “40°C to +85°C.
Output current is programmed via the I²C interface in 500-µA increments with clock rates up to 400 kHz. I²C inputs set the internal DAC output voltage used as a reference for linear current control using a MOSFET output sink transistor. A logic low input on the SLEEPZ input will put the A3904 into sleep mode and reduce the supply current to <0.5-µA.
The A3904 is supplied at three levels of packaging: 6-contact DFN package (suffix EW) with thin profile (0.38 mm nominal overall height) and exposed tab for enhanced thermal dissipation, bare die form on wafer (suffix CW), and 6-ball wafer level chip scale (WLCSP) bumped package (suffix CG). All package options are Pb (lead) free.
Availability: The EW and CW packages are available now. Samples of the CG are currently available and production shipments are expected to begin in December 2007. Lead time is 12-weeks.
Pricing: at $0.57 in quantities of 1,000.
Allegro MicroSystems Inc., 1-508-853-5000, www.allegromicro.com