Analog Devices Inc./Maxim Integrated MAX792SCPE+

Overview

MAX792SCPE+ 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, guaranteed RESET validity down to VCC = 1V, and 200ms reset timeout - used in embedded controllers and industrial instrumentation requiring reliable brownout and software fault recovery.

For engineers reviewing the MAX792SCPE+ datasheet, MAX792SCPE+ pinout, MAX792SCPE+ application, or MAX792SCPE+ equivalent, this page delivers verified functional identity, exact pin roles, real-world timing behavior (e.g., 12µs MR-to-RESET delay), memory write-cycle completion support, and validated alternative options for µP supervisory replacement in safety-critical power monitoring designs.

Technical Context

The MAX792SCPE+ implements dual-comparator architecture: one for reset assertion at 4.62V ±3% (internal mode), another for low-line warning 120mV above reset threshold. Its watchdog uses an external capacitor on SWT pin to set timeout (1.6s nominal with SWT = VCC), and includes WDPO for advance fault signaling prior to WDO assertion.

It integrates a bidirectional CE transmission gate with ≤10ns propagation delay and automatic disable during reset to prevent RAM corruption; CE IN becomes high-impedance when reset is active, and CE OUT holds low for 15µs after reset assertion if CE IN was low - ensuring write-cycle completion before power collapse.

Key Specifications

Pinout & Package

MAX792SCPE+ is housed in a 16-pin plastic DIP (dual in-line package) with 0.3-inch body width and through-hole mounting. Pin spacing is 0.1 inch, lead finish is lead-free (indicated by '+' suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX692ACPE+ and TPS3823-46DBVR, the MAX792SCPE+ uniquely integrates low-line NMI, pulsed watchdog (WDPO), and chip-enable gating - making it irreplaceable in applications demanding coordinated power-fail response, firmware fault recovery, and nonvolatile memory integrity assurance.

Availability

MAX792SCPE+ is available at Aetrix Electronics and suitable for industrial PLCs, medical instrumentation, telecom line cards, and automotive body control modules requiring stable component supply with long-term lifecycle support.

Supply support for MAX792SCPE+ 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, medical, and communications systems.

The MAX792SCPE+ belongs to Maxim's microprocessor supervisory product line, engineered specifically for robust power-monitoring and fault-recovery in embedded systems where deterministic reset behavior, memory write protection, and early power-degradation warning are critical.

FAQ

What is the exact reset threshold voltage for MAX792SCPE+?

The MAX792SCPE+ has a nominal reset threshold voltage of 4.62V in internal threshold mode, with ±3% accuracy over temperature and supply variations. This value is factory-trimmed and specified in the Electrical Characteristics table under "MAX792L" variant designation. The 'S' suffix in MAX792SCPE+ confirms the 4.62V threshold option, distinct from other variants like MAX792TCPE+ (3.06V) or MAX792RCPE+ (2.61V).

Does MAX792SCPE+ support external reset threshold programming?

Yes, MAX792SCPE+ supports external reset threshold programming via the RESET IN/INT and LLIN/REFOUT pins. When RESET IN/INT is pulled above 600mV (e.g., using a resistor divider), the device enters external programming mode, disconnecting internal references and allowing user-defined reset and low-line thresholds. The MAX792SCPE+ datasheet provides equations and examples for calculating resistor values to achieve target thresholds such as 4.4V reset and 4.75V low-line.

How does the watchdog function operate in MAX792SCPE+?

The MAX792SCPE+ watchdog monitors the WDI pin for transitions. If no edge occurs within the timeout period (1.6s nominal with SWT = VCC), WDPO pulses low first, followed 70ns later by WDO going low. WDO remains low until the next WDI transition. The timeout can be adjusted by connecting a capacitor from SWT to GND - e.g., a 100nF cap yields ~2.7s timeout at 5V (k = 16.2). Watchdog is disabled when VCC falls below the reset threshold.

What is the purpose of the CE IN and CE OUT pins on MAX792SCPE+?

The CE IN and CE OUT pins implement a transmission gate that passes chip-enable signals only when reset is inactive. During reset assertion, CE IN becomes high-impedance and CE OUT is forced high (or held low for 15µs if CE IN was low), preventing spurious memory writes. This ensures CMOS RAM or EEPROM write-cycle completion before power collapse - a key reliability feature absent in basic reset ICs. Propagation delay is guaranteed ≤10ns.

Can MAX792SCPE+ generate a nonmaskable interrupt (NMI)?

Yes, MAX792SCPE+ generates a nonmaskable interrupt via the LOW LINE output, which asserts low 120mV above the reset threshold (e.g., at ~4.74V for the 4.62V variant). This early warning signal is intended for connection to a µP's NMI pin, enabling firmware to perform critical save operations before reset occurs. The 15mV hysteresis on the low-line comparator prevents chatter during slow voltage decay.