Analog Devices Inc./Maxim Integrated MAX807MCPE+

Overview

The MAX807MCPE+ from Maxim Integrated is a full-featured microprocessor supervisory circuit designed for power monitoring, battery switchover, and watchdog protection in 5V µP systems. It provides active-low and active-high RESET outputs, manual reset input (MR), two-stage power-fail warning (PFI/PFO), low-line comparator (LOW LINE), BATT OK status flag, and independent watchdog timer with 1.6s timeout - all with ±1.5% reset threshold accuracy (4.425V) and guaranteed RESET validity down to VCC = 1V. It supports portable/battery-powered equipment requiring stable 250mA VCC-mode or 20mA battery-backup output drive.

For engineers reviewing the MAX807MCPE+ datasheet, MAX807MCPE+ pinout, MAX807MCPE+ application, or MAX807MCPE+ equivalent, key selection considerations include its 4.425V reset threshold, 200ms reset timeout, 2ns CE gate propagation delay, ±1.5% accuracy over temperature, and dual-supply switchover capability between VCC and VBATT for CMOS RAM backup.

Technical Context

The MAX807MCPE+ integrates six independent comparators (RESET, LOW LINE, PFI, BATT OK, battery switchover, and watchdog timeout detection) with internal timing logic and BiCMOS transmission gates. Its reset comparator uses precision bandgap reference and hysteresis (30–70mV), while the low-line comparator is offset +52mV above reset threshold with ±1.5% accuracy and 13mV hysteresis.

It implements chip-enable gating via a series transmission gate (75Ω typical on-resistance) with 2ns propagation delay at 50pF load, and supports automatic battery switchover using dual N-channel MOSFET control with VCC-to-OUT and BATT-to-OUT on-resistances of 1.2Ω and 16Ω respectively. The watchdog timer resets on WDI edge transitions and asserts WDO if no toggle occurs within 1.6s (typ).

Key Specifications

Pinout & Package

MAX807MCPE+ is supplied in a 16-pin plastic DIP package (0.300" wide), with through-hole mounting and industry-standard pin spacing. Pin functions are electrically validated per Maxim's official datasheet revision 4 (11/05).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar µP supervisory applications.

Compared with MAX809SCPA+ and TPS3823MPDBVR, the MAX807MCPE+ uniquely combines ±1.5% 4.425V reset accuracy, dual RESET outputs, integrated CE gating, low-line warning, and automatic battery switchover - making it the only option among the three that fully supports robust 5V µP systems with RAM retention and orderly shutdown requirements.

Availability

MAX807MCPE+ is available at Aetrix Electronics and suitable for industrial control PLCs, portable medical devices, embedded data loggers, and point-of-sale terminals requiring stable component supply with long-term lifecycle assurance.

Supply support for MAX807MCPE+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, automotive, and computing applications.

The MAX807 belongs to Maxim's µP supervisory product line, engineered specifically for mission-critical 5V systems needing precision reset, battery-backed memory retention, and hardware-enforced watchdog safety - not general-purpose voltage monitoring.

FAQ

What is the exact reset threshold voltage of the MAX807MCPE+?

The MAX807MCPE+ has a nominal reset threshold of 4.425V with ±1.5% accuracy over temperature (-40°C to +85°C). This value is specified in the Electrical Characteristics table under VRST for the MAX807M variant and confirmed in the ordering information section of the datasheet. The threshold remains stable across VCC supply variations and ensures reliable reset assertion before 5V system logic margins are violated.

Does the MAX807MCPE+ support automatic switchover between main supply and backup battery?

Yes, the MAX807MCPE+ supports automatic battery switchover: when VCC falls below the battery voltage and the reset threshold, the OUT pin disconnects from VCC and connects to BATT. The switchover threshold is VBATT − 0.2V (min), and the BATT-to-OUT on-resistance is 16Ω max, enabling up to 20mA at <100mV dropout. This function is explicitly detailed in the Pin Description and Detailed Description sections of the MAX807 datasheet.

Can the MAX807MCPE+ generate a non-maskable interrupt (NMI) before system reset occurs?

Yes, the MAX807MCPE+ provides two dedicated NMI-capable outputs: LOW LINE asserts low when VCC drops to 52mV above the 4.425V reset threshold, and PFO asserts low when PFI falls below 2.265V. Both are CMOS outputs with 3.2mA sink capability and sub-30µs propagation delay, enabling µP firmware to initiate an orderly shutdown routine with guaranteed timing margin before RESET activation.

What is the watchdog timeout period of the MAX807MCPE+ and how is it triggered?

The MAX807MCPE+ watchdog timeout period is 1.6 seconds (typical), measured from the last WDI edge transition. It is triggered when WDI remains static (high or low) beyond this interval, causing WDO to assert low. The timer clears immediately upon RESET assertion or any WDI edge while RESET is deasserted. This behavior is documented in the Watchdog Input and Watchdog Output sections of the datasheet, including timing diagrams and functional descriptions.

Is the MAX807MCPE+ pinout compatible with other MAX807 variants like MAX807L or MAX807N?

Yes, the MAX807MCPE+ shares identical pinout, package (16-pin DIP), and functional block diagram with MAX807L and MAX807N. The only difference is the reset threshold voltage: 4.675V (L), 4.425V (M), and 4.575V (N). All electrical characteristics, timing parameters, and pin functions - including CE gating, LOW LINE, BATT OK, and watchdog behavior - are fully consistent across the MAX807L/M/N family as stated in the datasheet title and ordering information.