MAXIM MAX819MESA+

The MAX817/MAX818/MAX819 microprocessor (µP) supervisory circuits simplify power-supply monitoring, battery control, and chip-enable gating in µP systems by reducing the number of components required. These devices are designed for use in +5V -powered systems. Low supply current (11µA typical) and small package size make these devices ideal for portable applications. The MAX817/MAX818/MAX819 are specifically designed to ignore fast transients on VCC. Other supervisory functions include active-low reset, backup battery switchover, watchdog input, battery freshness seal, and chip-enable gating.

These devices offer two pretrimmed reset threshold voltages for ±5% or ±10% power supplies: 4.65V for the L versions and 4.40V for the M versions. The MAX817/ MAX818/MAX819 are available in space-saving µMAX packages, as well as 8-pin DIP/SO.

• Precision Supply-Voltage Monitor: 4.65V (MAX81_L) 4.40V (MAX81_M)
• 11µA Quiescent Supply Current
• 200ms Reset Time Delay
• Watchdog Timer with 1.6sec Timeout (MAX817/MAX818)
• Battery-Backup Power Switching; Battery Voltage Can Exceed VCC
• Battery Freshness Seal
• On-Board, 3ns Gating of Chip-Enable Signals (MAX818)
• Uncommitted Voltage Monitor for Power-Fail or Low-Battery Warning (MAX817/MAX819)
• Manual Reset Input (MAX819)

• Battery-Powered Computers and Controllers
• Embedded Controllers
• Intelligent Instruments
• Critical µP Monitoring
• Portable Equipment