Analog Devices Inc. ADM693ARZ

Overview

ADM693ARZ from Analog Devices is a 16-pin SOIC microprocessor supervisory circuit providing precision reset generation (4.4 V threshold), adjustable watchdog timeout (100 ms / 1.6 s / user-configurable), battery backup switchover (2.0–4.0 V VBATT range), CE signal gating (5 ns propagation), and power-fail warning (1.3 V PFI comparator). It ensures reliable system startup, brownout recovery, and RAM data integrity in industrial controllers.

For engineers reviewing the ADM693ARZ datasheet, ADM693ARZ pinout, ADM693ARZ application, or ADM693ARZ equivalent, this page delivers verified specifications, validated pin functions, real-world use cases for battery-backed systems, and confirmed alternative parts with documented functional differences.

Technical Context

The ADM693ARZ integrates a precision voltage detector (4.4 V ±0.15 V), dual-mode watchdog timer (internal oscillator or external clock/capacitor), and bidirectional battery switchover circuit with 70 mV turn-on and 50 mV turn-off thresholds. Its CE gating logic forces CEOUT high during VCC undervoltage, preventing spurious writes to CMOS RAM.

It features three dedicated status outputs-BATT ON (active-high battery selection indicator), LOW LINE (active-low VCC monitor), and WDO (watchdog timeout flag)-plus separate RESET (active-low) and RESET (active-high) outputs. All digital outputs drive ≥1.6 mA sink at VCC ≥ 4.25 V.

Key Specifications

Pinout & Package

ADM693ARZ is housed in a 16-lead SOIC (R-16) package with 1.27 mm pitch, JEDEC MS-012AC compliant, and rated for –40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX693AESA+ and TPS3823MPW, ADM693ARZ uniquely combines adjustable timing, dual reset polarity, CE gating, and integrated battery switchover in a single 16-pin SOIC-enabling compact, robust, and field-upgradable supervisory designs where RAM data integrity and flexible watchdog behavior are mandatory.

Availability

ADM693ARZ is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive telematics modules, and medical infusion pumps requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for ADM693ARZ 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 ADM690–ADM695 family was designed specifically for microprocessor system reliability-integrating reset, watchdog, battery switchover, CE gating, and power-fail detection into single-chip solutions for mission-critical embedded applications.

FAQ

What is the guaranteed reset voltage threshold range for ADM693ARZ?

The ADM693ARZ has a guaranteed reset voltage threshold range of 4.25 V to 4.48 V at +25°C, with typical value 4.4 V. This specification ensures compatibility with 5 V ±10% power supplies and remains stable across the full –40°C to +85°C operating temperature range per datasheet Figure 13. The 40 mV hysteresis prevents oscillation during slow VCC transitions. ADM693ARZ uses this precise threshold to assert RESET reliably before µP operation becomes unstable.

How does ADM693ARZ handle battery switchover during power-down?

During power-down, ADM693ARZ switches VOUT from VCC to VBATT when VCC falls 50 mV below VBATT, with 20 mV hysteresis to prevent chattering. In battery backup mode, VOUT delivers VBATT – 0.02 V at 250 µA load, and supply current drops to ≤1 µA. The BATT ON output goes high to indicate VBATT is active, and CEOUT is forced high to block memory writes. ADM693ARZ maintains these states until VCC recovers above VBATT + 70 mV.

Can ADM693ARZ generate an adjustable reset pulse width?

Yes, ADM693ARZ supports adjustable reset pulse width via OSC SEL and OSC IN pins. With OSC SEL floating or high, connecting OSC IN low selects 50 ms (typical); with OSC SEL low, an external capacitor on OSC IN sets pulse width as 260 ms × C/47 pF. This configurability allows alignment with µP-specific reset timing requirements. ADM693ARZ implements this using its internal oscillator or external RC network-no additional components needed beyond the capacitor.

What is the purpose of the CEIN and CEOUT pins on ADM693ARZ?

The CEIN and CEOUT pins implement hardware-enforced memory write protection: CEOUT is a gated replica of CEIN with 5 ns propagation delay during normal operation, but is forced high whenever VCC falls below the 4.4 V reset threshold. This instantly disables chip enable to battery-backed CMOS RAM, preventing corrupted writes during brownout. ADM693ARZ uses this feature to guarantee data integrity without software intervention or external logic.

Does ADM693ARZ provide both active-low and active-high reset outputs?

Yes, ADM693ARZ provides two independent reset outputs: RESET (active-low) and RESET (active-high), both asserted simultaneously when VCC drops below threshold or watchdog times out. The active-high output eliminates need for external inverters in systems requiring high-true reset signals. ADM693ARZ drives both outputs with guaranteed voltage levels-RESET ≤ 0.4 V at 1.6 mA sink, RESET ≥ 3.5 V at 1 µA source-ensuring direct interface to modern µPs.