Analog Devices Inc./Maxim Integrated MAX792LCPE+

Overview

MAX792LCPE+ from Maxim Integrated is a microprocessor supervisory circuit providing reset generation, manual reset input, two-stage power-fail warning, watchdog timer with pulsed fault output, and chip-enable gating for nonvolatile memory protection. It features 4.62V internal reset threshold, 200ms reset timeout, and guaranteed RESET validity down to VCC = 1V. Used in embedded controllers and critical µP power monitoring systems where brownout immunity and write-cycle completion are essential.

For engineers reviewing the MAX792LCPE+ datasheet, MAX792LCPE+ pinout, MAX792LCPE+ application, or MAX792LCPE+ equivalent, key selection criteria include internal 4.62V reset threshold accuracy, 1.6s nominal watchdog timeout (SWT-connected), 10ns CE propagation delay, and compatibility with 5V/3V supply rails in industrial temperature range (0°C to +70°C).

Technical Context

The MAX792LCPE+ integrates independent reset, low-line, overvoltage, and watchdog comparators with internal 1.30V reference and programmable thresholds via external resistor dividers. Its dual reset outputs (RESET and RESET) support both active-high and active-low µP interfaces, while the CE IN/CE OUT transmission gate enforces memory write-cycle completion during power transitions.

Watchdog operation is triggered by WDI state stagnation beyond the timeout period set by SWT capacitor or internal 1.6s default; WDPO provides advance pulse warning before WDO assertion. The device operates in two modes: internal threshold mode (RESET IN/INT ≤60mV) and external programming mode (RESET IN/INT ≥600mV), enabling flexible voltage monitoring across regulated/unregulated rails.

Key Specifications

Pinout & Package

MAX792LCPE+ is housed in a 16-pin plastic DIP (Dual In-line Package) with 0.3-inch body width and standard through-hole footprint. Pin 1 is marked with dot or notch orientation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX823SESA+ and TPS3823MPW, the MAX792LCPE+ uniquely combines 4.62V precision reset, dual reset outputs, LOW LINE NMI, watchdog with pulse warning, and chip-enable gating in a single DIP package - making it irreplaceable for systems requiring coordinated power-fail response and memory write integrity.

Availability

MAX792LCPE+ is available at Aetrix Electronics and suitable for industrial controllers, medical diagnostic instruments, embedded data loggers, and communications baseband processors requiring stable component supply with long-term manufacturability and traceable sourcing.

Supply support for MAX792LCPE+ 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) designs precision analog and mixed-signal ICs for power management, sensing, and interface applications in industrial, automotive, and communications markets.

The MAX792/MAX820 product line delivers integrated microprocessor supervisory functions - including reset, watchdog, low-line warning, and memory write protection - specifically for systems lacking battery backup where deterministic power-fail response is critical.

FAQ

What is the exact reset threshold voltage of the MAX792LCPE+?

The MAX792LCPE+ has a nominal internal reset threshold voltage of 4.62V, with ±3% tolerance over temperature and supply variations. This value is factory-trimmed and applies in internal threshold mode when RESET IN/INT is grounded. The threshold remains stable across the 0°C to +70°C operating range, with normalized drift less than ±1.5% over temperature per the typical operating characteristics graph.

Does the MAX792LCPE+ support watchdog functionality with adjustable timeout periods?

Yes, the MAX792LCPE+ supports adjustable watchdog timeout via the SWT pin. With SWT tied to VCC, the nominal timeout is 1.6 seconds. Connecting an external capacitor from SWT to GND sets alternative timeouts: for VCC = 5V, timeout = 16.2 × C (nF) ms; for VCC = 3V, timeout = 27 × C (nF) ms. Capacitor values must exceed 4.7nF, and SWT must never be left floating or grounded.

How does the chip-enable gating function protect memory in the MAX792LCPE+?

The MAX792LCPE+ uses a transmission gate between CE IN and CE OUT that disables during reset assertion. If CE IN is low when reset activates, CE OUT stays low for 15µs to complete the current memory write cycle. This prevents partial writes and data corruption during power-down sequences - a critical feature for CMOS RAM, EEPROM, and FRAM interfacing without software intervention.

Can the MAX792LCPE+ monitor both overvoltage and undervoltage conditions simultaneously?

Yes, the MAX792LCPE+ independently monitors overvoltage and undervoltage. The OVI/OVO comparator detects overvoltage (OVI > 1.30V → OVO low), while the internal reset and low-line comparators detect undervoltage (VCC < 4.62V → RESET low; VCC < 4.74V → LOW LINE low). These functions operate concurrently and do not interfere - OVO is uncommitted and has no effect on reset or watchdog behavior.

What is the purpose of the RESET IN/INT pin on the MAX792LCPE+?

The RESET IN/INT pin on the MAX792LCPE+ selects operating mode: grounding it (≤60mV) enables internal threshold mode with factory-set 4.62V reset and 4.74V low-line thresholds; pulling it ≥600mV enables external programming mode, disconnecting internal dividers and routing LLIN/REFOUT and RESET IN/INT to external resistor networks for custom threshold setting - supporting flexible rail monitoring in complex power architectures.