Microprocessor Supervisors Provide Battery Backup And CE Gating

The MAX16016/20/21/23/24 microprocessor supervisory circuits consume less than 1.2 ?A of quiescent current and feature precision power-supply monitoring and battery-control functions. Residing in TQFN or TDFN packages, they integrate a variety of features including a microprocessor reset circuit, battery-backup switchover, power-fail warning, and chip-enable (CE) gating. They automatically switch the real-time clock or RAM power source to the backup battery when Vcc falls below the reset threshold and Vbatt. A reset output asserts when Vcc is below the reset-threshold voltage for at least 145 ms after Vcc returns above its threshold. Each device offers an active-low, push-pull reset or an active-low, open-drain reset. A power-fail comparator signals an interrupt when Vpfi falls below 590 mV or when Vcc falls below the reset threshold. The MAX16016/20/21/24 include a battery-on output during battery-backup mode while the MAX16016/20/21 add a watchdog function. The MAX16020/21/24 provide gating of the CE signals and the MAX16023/24 integrate a low-dropout regulator capable of delivering up to 100 mA, a manual-reset input, and a user-adjustable reset input. Pricing starts at $2.48 each/1,000. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.