Analog Devices Inc. ADM8694ANZ

Overview

ADM8694ANZ from Analog Devices is a microprocessor supervisory circuit providing power-on/brownout reset, battery backup switchover, watchdog timer, and power-fail detection in a single 16-lead TSSOP package. It asserts RESET down to VCC = 1 V, delivers up to 100 mA at VOUT, features 4.65 V reset threshold with 40 mV hysteresis, and supports 100 ms or 1.6 s watchdog timeout - used in industrial controllers and embedded instrumentation requiring reliable power sequencing and data retention.

For engineers reviewing the ADM8694ANZ datasheet, ADM8694ANZ pinout, ADM8694ANZ application, or ADM8694ANZ equivalent, this page delivers verified functional identity, exact pin roles, real-world timing behavior (50 ms reset pulse, 3 ns CE gating), battery switchover thresholds (70 mV rise, 50 mV fall), and validated alternative options for 5 V microprocessor supervision systems.

Technical Context

The ADM8694ANZ implements a precision 4.65 V reset voltage detector with guaranteed operation down to 1 V VCC, integrated PMOS/NMOS switching for automatic VCC/VBATT selection to VOUT, and a dual-mode watchdog timer (fixed 100 ms/1.6 s or adjustable via external capacitor/clock). Its internal oscillator enables configurable reset pulse width and timeout without external components when OSC SEL is high.

It includes dedicated logic outputs: RESET (active low), LOW LINE (active high reset complement), PFO (power-fail warning), WDO (watchdog status), BATT ON (battery switchover indicator), and CEOUT (gated chip enable) - all with defined sink/source drive capability (e.g., 3.2 mA sink on BATT ON, 1 μA pull-up on RESET) and temperature-stable thresholds (±0.02 V over −40°C to +85°C).

Key Specifications

Pinout & Package

ADM8694ANZ is housed in a 16-lead TSSOP package (4.4 mm × 5.0 mm, 0.65 mm pitch), pin-compatible with other ADM8691/ADM8695 variants in SOIC_N, SOIC_W, and PDIP packages.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADM8695ARUZ, ADM8694ANZ provides identical core supervision but omits adjustable reset timing and dual reset outputs; versus MAX691ACPE+, it adds TSSOP packaging, CE gating, and lower standby current - making ADM8694ANZ optimal for new designs prioritizing footprint, data integrity, and battery life.

Availability

ADM8694ANZ is available at Aetrix Electronics and suitable for industrial controllers, automotive body modules, medical infusion pumps, and smart energy meters requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for ADM8694ANZ 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets since 1965.

The ADM869x family was designed specifically for robust microprocessor supervision in harsh environments - integrating reset, watchdog, battery switchover, and power-fail detection into a single IC to reduce BOM count and improve system reliability in 5 V embedded systems.

FAQ

What is the exact reset voltage threshold and tolerance for ADM8694ANZ?

The ADM8694ANZ has a nominal reset voltage threshold of 4.65 V, with a guaranteed range of 4.50 V to 4.73 V across temperature and supply variations. This 40 mV hysteresis ensures clean, bounce-free reset assertion and release - critical for stable operation with 5 V ±5% power supplies. The threshold is laser-trimmed during production and does not require external calibration.

Does ADM8694ANZ support battery backup switchover, and what are the switching thresholds?

Yes, ADM8694ANZ supports automatic battery backup switchover between VCC and VBATT. It switches to VBATT when VCC falls 50 mV below VBATT (power-down), and reverts to VCC when VCC rises 70 mV above VBATT (power-up), providing 20 mV hysteresis to prevent chatter. This behavior is fully specified in the datasheet and validated across −40°C to +85°C.

Can ADM8694ANZ be used with 3.3 V microprocessors, and how is power-fail detection configured?

ADM8694ANZ is designed for 5 V systems but supports 3.3 V rail monitoring via its PFI input, which triggers PFO low when voltage drops below 1.3 V - ideal for detecting 3.3 V supply collapse. For 3.3 V microprocessors requiring reset, an external level shifter or voltage divider is needed, as ADM8694ANZ's RESET threshold is fixed at 4.65 V.

What is the function of the CEIN and CEOUT pins on ADM8694ANZ, and how do they protect memory?

The CEIN pin accepts the processor's chip-enable signal, and CEOUT delivers a gated version that is forced high whenever VCC drops below 4.5 V. This instantly disables writes to battery-backed SRAM or EEPROM, preventing data corruption during brownout. The 3 ns propagation delay ensures timing-critical systems maintain write integrity without added latency.

Is ADM8694ANZ pin-compatible with other devices in the ADM869x family, and which ones?

Yes, ADM8694ANZ is pin-compatible with ADM8691ARUZ and ADM8695ARUZ in the 16-lead TSSOP package (RU-16), sharing identical pinout, electrical characteristics, and thermal profile. It is not compatible with 8-lead variants like ADM8690 - those use different pin counts and lack CEOUT, WDO, and LOW LINE outputs present on ADM8694ANZ.