The MAX801/MAX808 microprocessor (µP) supervisory circuits monitor and control the activities of +5V µPs by providing backup-battery switchover, low-line indication, and µP reset. Additional features include a watchdog for the MAX801 and CMOS RAM write protection for the MAX808. The MAX801/MAX808 offer a choice of reset-threshold voltage (denoted by suffix letter): 4.675V (L), 4.575V (N), and 4.425V (M). These devices are available in 8-pin DIP and SO packages.
The Maxim MAX801 and MAX808 are 8‑pin microprocessor supervisory circuits that monitor +5 V uP supplies, provide backup‑battery switchover, low‑line indication, and reset functions. The MAX801 adds a watchdog timer, while the MAX808 includes CMOS RAM write‑protect.
The devices are offered in L, N, and M variants with reset‑threshold voltages of 4.675 V, 4.575 V, and 4.425 V respectively, and are available in 8‑pin DIP, SO, and CERDIP packages. Typical supply current is 68 µA for MAX801 and 48 µA for MAX808, with battery‑standby currents below 1 pA.
| Reset‑threshold voltage (L) | 4.675 V |
|---|---|
| Reset‑threshold voltage (N) | 4.575 V |
| Reset‑threshold voltage (M) | 4.425 V |
| Low‑line threshold above reset | 52 mV |
| Supply current (normal mode, MAX801) | 68 µA |
| Watchdog timeout period | 1.12 – 2.24 s |
The devices offer three reset‑threshold options identified by the suffix: L = 4.675 V, N = 4.575 V, and M = 4.425 V.
Typical supply current for the MAX801 in normal mode is 68 µA.
The watchdog timer can be set for a timeout period between 1.12 s and 2.24 s.