MAX818L, MAX818M

+5V Microprocessor Supervisory Circuits

Low-Power, Small Size Microprocessor Supervisory Circuit with Battery-Backup

Please check latest availability status for a specific part variant.


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. The Selector Guide in the full data sheet lists the specific functions available from each device.

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.
MAX817L, M, MAX818L, M, MAX819L, M: Typical Operating Circuit MAX817L, M, MAX818L, M, MAX819L, M: Typical Operating Circuit Enlarge+

Key Features

  • 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/Controllers
  • Critical µP Monitoring
  • Embedded Controllers
  • Intelligent Instruments
  • Portable Equipment

Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.
Request Reliability Report for: MAX818L  MAX818M 
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

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