Battery Monitors Include Hysterisis And µP Supervisor

The adjustable MAX6846 single-level and MAX6849 dual-level battery monitors integrate hysterisis and independent microprocessor supervisory reset circuits into eight-pin SOT23 packages. Both devices monitor single-cell lithium-ion or multi-cell NiMH/NiCd/alkaline batteries while consuming just 2.5 µA. The microprocessor supervisory circuit monitors system voltages from 1.8V to 3.3V via seven factory-trimmed reset thresholds, with two reset timeout options of 150 ms or 1200 ms. Other features include user-adjustable voltage-trip thresholds, a low-battery output that can be used to shut the system off when the battery is dead, and an additional low-battery output that can provide an early low-battery warning. Price for either device is $1.30 each/2,500. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.