Low-Voltage, SOT23, µP Supervisors with Power-Fail In/Out, Manual Reset, and Watchdog Timer

The MAX6701—MAX6708 microprocessor (µP) supervisory circuits reduce the complexity and components required to monitor power-supply functions in µP systems. These devices significantly improve system reliability and accuracy compared to separate ICs or discrete components.

The MAX6701—MAX6708 family provides four functions: a reset output during power-up, power-down, and brownout conditions; an independent watchdog output that goes low if the watchdog input has not been toggled within 1.6s; a 0.62V threshold detector for power-fail warning; and an active-low manual reset input.

The MAX6701—MAX6708 family offers several pinout options to accommodate a variety of multivoltage microprocessor supervision applications.

The MAX6701(A)/MAX6702(A)/MAX6703(A) monitor three supply voltages (one fixed threshold and two adjustable) to drive a single reset output and include a manual reset input and a watchdog timer with an independent output. The MAX6704 monitors a single-supply voltage to drive complementary reset outputs and includes an independent adjustable power-fail-in/power-fail-out comparator, a manual reset input, and a reset-based watchdog timer. The MAX6705(A)/MAX6706(A)/MAX6707(A) monitor a single-supply voltage to drive a single reset output and include an independent adjustable power-fail-in/power-fail-out comparator, a manual reset input, and a watchdog timer with an independent output. The MAX6708 is the same as the MAX6704 but without the watchdog timer function.

See the Detailed Description for differences between non-A and A versions.

Applications

* Computers * Controllers * Critical µP Power Monitoring * Intelligent Instruments * Networking * Telecommunications * White Goods

* Small 8-Pin SOT23 Package* Precision Monitoring of +5.0V, +3.3V, +3.0V, +2.5V Supply Voltages* 140ms Reset Timeout Delay* Power-Fail Input with Independent Output; Monitor Inputs Down to 0.62V (MAX6704—MAX6708)* Dual Adjustable Reset Input for Triple-Voltage Monitoring (MAX6701(A)/MAX6702(A)/MAX6703(A))* 1.6s Watchdog Timeout Period (MAX6701(A)—MAX6707(A))* Independent Watchdog Output (MAX6701(A)/MAX6702(A)/MAX6703(A)/MAX6705(A)/MAX6706(A)/MAX6707(A))* Manual Reset Input* Four Reset Output Stage Options

* Active Low Push-Pull (MAX6701(A), MAX6705(A))* Active Low Open Drain (MAX6703(A), MAX6707(A))* Active High Push-Pull (MAX6702(A), MAX6706(A))* Dual Active Low/High Push-Pull (MAX6704, MAX6708)

* Guaranteed Reset Valid to VCC = 1V* Immune to Short Falling VCC Transients* Low Cost, Few External Components