Analog Devices Inc. ADM693AARWZ

Overview

ADM693AARWZ from Analog Devices is a microprocessor supervisory circuit integrating voltage monitoring, watchdog timer, battery backup switchover, chip enable gating, and power-fail detection in a single 16-pin SOIC-Wide (R-16W) package. It provides 4.4 V ±3% reset threshold, 200 ms or adjustable reset timeout, 100 ms/1.6 s selectable watchdog timeout, automatic VCC/VBATT switchover with ≤0.75 Ω on-resistance, and 1.25 V PFI comparator - deployed in industrial controllers and automotive ECUs for reliable power-up/down sequencing and brownout recovery.

For engineers reviewing the ADM693AARWZ datasheet, ADM693AARWZ pinout, ADM693AARWZ application, or ADM693AARWZ equivalent, this page delivers verified functional identity, validated pin roles, confirmed timing parameters, real-world use cases in battery-backed RAM systems, and two technically documented alternative parts with explicit differences in reset threshold and tolerance.

Technical Context

The ADM693AARWZ implements a dual-threshold voltage detector (4.4 V ±3%) with 15 mV hysteresis, enabling robust operation across 4.5–5.5 V VCC supply range. Its integrated PMOS/NMOS switchover architecture supports seamless transition between VCC and VBATT down to 1 V VCC, maintaining VOUT regulation with <0.05 V dropout at 25 mA and <0.3 V at 250 mA.

Watchdog functionality uses either internal oscillator (100 ms or 1.6 s timeout) or external clock/capacitor configuration, with WDI input accepting three-level logic (0.8 V low, 0.75×VCC high) and auto-disabling when floating. CEIN-to-CEOUT gating features 6–10 ns propagation delay and 40–150 Ω on-resistance, ensuring precise RAM write protection during brownouts.

Key Specifications

Pinout & Package

ADM693AARWZ is housed in a 16-pin Wide SOIC (R-16W) package, 10.3 mm × 7.5 mm, 1.27 mm pitch, with exposed pad not present. Pin functions are electrically validated per Analog Devices datasheet Rev. 0.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADM693AARWZ, ADM691AARWZ raises reset threshold by 0.25 V - reducing false resets on noisy rails but increasing risk of late assertion during marginal 5 V droop; ADM800MARWZ improves threshold tolerance from ±3% to ±2%, enhancing consistency across temperature and lot variation without changing layout or firmware.

Availability

ADM693AARWZ is available at Aetrix Electronics and suitable for industrial controllers, automotive ECUs, medical infusion pumps, and point-of-sale terminals requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for ADM693AARWZ 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 ADM69x family was designed specifically for microprocessor system supervision - integrating reset, watchdog, battery switchover, and power-fail detection into one IC to replace discrete solutions in space-constrained embedded designs.

FAQ

What is the exact reset voltage threshold and tolerance for ADM693AARWZ?

The ADM693AARWZ has a guaranteed reset voltage threshold of 4.4 V with ±3% tolerance (4.25 V to 4.50 V) across –40°C to +85°C. This is explicitly specified in the datasheet Rev. 0 "RESET AND WATCHDOG TIMER" table and distinguishes it from the 4.65 V threshold of ADM691A. The threshold remains stable with VCC as low as 1 V, ensuring reliable reset hold-down during deep brownouts.

Can ADM693AARWZ operate with a 3.3 V main supply?

No - ADM693AARWZ requires VCC between 4.5 V and 5.5 V per its Absolute Maximum Ratings and specifications table. It is not rated for 3.3 V operation. Attempting to power ADM693AARWZ from 3.3 V will result in undefined behavior, failure to assert RESET, or damage. For 3.3 V systems, consider Analog Devices' ADM6315 or similar 3.3 V supervisory ICs instead of ADM693AARWZ.

How does the battery switchover work on ADM693AARWZ, and what is the switchover hysteresis?

ADM693AARWZ automatically switches VOUT from VCC to VBATT when VCC falls below VBATT – 0.03 V (power-down) and back to VCC when VCC rises above VBATT + 0.03 V (power-up), providing 60 mV hysteresis to prevent chattering. In battery mode, VOUT tracks VBATT with ≤0.3 V dropout at 10 mA, and supply current drops to 0.04 µA - enabling multi-year backup with standard coin cells. This behavior is confirmed in the "BATTERY BACKUP SWITCHING" section of the datasheet.

Is ADM693AARWZ pin-compatible with MAX693A?

Yes - ADM693AARWZ is a direct functional and pin-compatible upgrade for MAX693A, as stated in the datasheet's General Description: "The family of products provides an upgrade for the MAX691A/93A/800M family." Pin mapping, electrical characteristics, and timing parameters match, allowing drop-in replacement without PCB changes. However, note that ADM693AARWZ offers improved temperature stability and lower quiescent current versus legacy MAX parts.

What are the valid configurations for adjusting the watchdog timeout period on ADM693AARWZ?

ADM693AARWZ supports three watchdog timeout configurations: (1) OSC SEL floating/high + OSC IN grounded → 100 ms short timeout; (2) OSC SEL floating/high + OSC IN floating → 1.6 s long timeout; (3) OSC SEL grounded + OSC IN driven by external clock or 47 pF capacitor → adjustable timeout (Twd = 1024/fCLK or Twd = 600×C/47 pF). All modes are validated in Table II and Figure 18 of the datasheet Rev. 0.