General Description

The MAX706P/R/S/T, MAX706AP/AR/AS/AT, and MAX708R/S/T microprocessor (µP) supervisory circuits reduce the complexity and number of components required to monitor +3V power-supply levels in +3V to +5V µP systems. These devices significantly improve system reliability and accuracy compared to separate ICs or discrete components. The MAX706P/R/S/T and MAX706AP/AR/AS/AT supervi sory circuits provide the following four functions:
1) A reset output during power-up, power-down, and brownout conditions.
2) An independent watchdog output that goes low if the watchdog input has not been toggled within 1.6s.
3) A 1.25V threshold detector for power-fail warning, low-battery detection, or for monitoring a power supply other than the main supply.
4) An active-low, manual-reset input

Features

♦ µMAX Package, Small 8-Pin SO
♦ Precision Supply-Voltage Monitors
2.63V (MAX706P/R, MAX706AP/AR, and MAX708R)
2.93V (MAX706S, MAX706AS, and MAX708S)
3.08V (MAX706T, MAX706AT, and MAX708T)
♦ 200ms Reset Time Delay
♦ Debounced TTL/CMOS-Compatible Manual Reset Input
♦ 100µA Quiescent Current
♦ WDI Disable Feature (MAX706AP/AR/AS/AT)
♦ Watchdog Timer: 1.6s Timeout
♦ Reset Output Signal:
Active-High Only (MAX706P, MAX706AP)
Active-Low Only (MAX706R/S/T, MAX706AR/AS/AT)
Active-High and Active-Low (MAX708R/S/T)
♦ Voltage Monitor for Power-Fail or Low-Battery Warning
♦ 8-Pin Surface-Mount Package
♦ Guaranteed RESET Assertion to VCC = 1V

Applications

Battery-Powered Equipment
Portable Instruments
Computers
Controllers
Intelligent Instruments
Critical µP Power Monitoring