Analog Devices Inc./Maxim Integrated MAX693ACPE+

Overview

MAX693ACPE+ from Maxim Integrated is a microprocessor supervisory circuit providing power-on reset, watchdog timer, battery switchover, and chip-enable gating for 5V systems. It features a 4.4V typical reset threshold, 200ms reset timeout, 30μA operating current, and guaranteed RESET assertion down to VCC = 1V - used in embedded controllers and intelligent instruments requiring reliable brownout protection.

For engineers reviewing the MAX693ACPE+ datasheet, MAX693ACPE+ pinout, MAX693ACPE+ application, or MAX693ACPE+ equivalent, key selection criteria include reset threshold accuracy (±150mV), battery-backup mode operation with VBATT ≥ 2.0V, CE IN-to-CE OUT propagation delay ≤10ns, and compatibility with MaxCap®/supercapacitor backup solutions.

Technical Context

The MAX693ACPE+ integrates a precision voltage monitor, dual reset outputs (active-low RESET and active-high RESET), a programmable watchdog timer with selectable timeout periods (100ms or 1.6s), and bidirectional chip-enable signal gating. Its internal oscillator or external capacitor/clock input sets timing parameters, while the battery switchover comparator activates when VCC falls below VBATT − 0.3V.

It implements a PMOS-based VCC-to-VOUT switch (R_ON ≤1.4Ω) and separate VBATT-to-VOUT path (R_ON ≤30Ω), supports write-protection of CMOS RAM/EEPROM via CE gating, and delivers valid reset signaling even during deep brownout (VCC = 1V) using an open-drain RESET output with external pulldown.

Key Specifications

Pinout & Package

MAX693ACPE+ is housed in a 16-pin plastic DIP (dual in-line package) with 0.3-inch body width and through-hole mounting. Pin 1 is VBATT; pin 16 is RESET (active-high, open-drain).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX693ACPE+, MAX691ACPE+ offers higher reset threshold but no guaranteed PFI accuracy, while MAX800MCPE+ adds industrial temperature rating and certified ±2% PFI tolerance - making it preferable for harsh-environment designs demanding traceable power-fail detection.

Availability

MAX693ACPE+ is available at Aetrix Electronics and suitable for industrial controllers, intelligent instrumentation, and critical μP power monitoring applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant through-hole packaging.

Supply support for MAX693ACPE+ 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, computing, and communications markets.

The MAX691A/MAX693A family delivers integrated power supervision, watchdog, and backup control for 5V microprocessor systems - targeting reliability-critical embedded applications where deterministic reset behavior and battery switchover integrity are mandatory.

FAQ

What is the reset threshold voltage for MAX693ACPE+?

The MAX693ACPE+ has a typical reset threshold voltage of 4.40V, with a specified range of 4.25V to 4.50V over temperature and supply variations. This threshold is factory-trimmed and applies to both power-up and power-down conditions. The MAX693ACPE+ uses this voltage to assert RESET and RESET outputs whenever VCC falls below the threshold, ensuring consistent behavior across its operating temperature range of 0°C to +70°C.

Does MAX693ACPE+ support battery backup with supercapacitors?

Yes, MAX693ACPE+ is explicitly designed for MaxCap® and supercapacitor compatibility. Its VBATT input supports low-leakage backup sources, and the internal switchover comparator activates when VCC drops below VBATT − 0.3V. In battery-backup mode, VOUT is sourced from VBATT with ≤30Ω on-resistance, and supply current drops to ≤1μA - enabling multi-hour retention with typical 0.47F supercapacitors charged to 2.8V.

How does the watchdog timer function in MAX693ACPE+?

The MAX693ACPE+ watchdog monitors the WDI pin: if WDI remains static (high or low) longer than the programmed timeout (100ms or 1.6s), WDO goes low and RESET/RESET are asserted for 200ms. A transition or ≥100ns pulse at WDI resets the timer. Leaving WDI unconnected disables the watchdog via internal 1.6V biasing. The timeout is set via OSC SEL and OSC IN configuration per Table 1 in the datasheet.

Can MAX693ACPE+ operate with VCC below 1V?

No - MAX693ACPE+ requires VCC ≥ 1V for functional operation. However, its RESET output remains valid (i.e., correctly asserted low) down to VCC = 1V, and with an external 10kΩ pulldown resistor, RESET validity extends to VCC = 0V. Below 1V, internal gate drive weakens, increasing RESET saturation voltage; the device itself ceases normal operation, entering undefined state below absolute minimum VCC of −0.3V.

What package type is used for MAX693ACPE+?

MAX693ACPE+ is supplied in a 16-pin plastic DIP (dual in-line package) with 0.3-inch body width and through-hole leads. The "+" suffix denotes lead-free (RoHS-compliant) finish. This package supports manual soldering and socket-based prototyping, and is rated for 0°C to +70°C operation. Thermal dissipation is 842mW at +70°C, derating 10.53mW/°C above that temperature.