Analog Devices Inc. ADM8693ARUZ

Overview

ADM8693ARUZ from Analog Devices is a 16-lead TSSOP microprocessor supervisory circuit providing precision reset generation, adjustable watchdog timer (100 ms / 1.6 s / adjustable), battery backup switchover (VCC/VBATT to VOUT), power-fail warning (1.3 V PFI threshold), and CE signal gating with 3 ns propagation delay - all operating down to VCC = 1 V. It serves as a single-chip power integrity manager in industrial controllers and embedded systems requiring reliable brownout recovery and RAM write protection.

For engineers reviewing the ADM8693ARUZ datasheet, ADM8693ARUZ pinout, ADM8693ARUZ application, or ADM8693ARUZ equivalent, key selection criteria include its 4.40 V reset threshold, dual-mode watchdog timeout configurability, active-low RESET with guaranteed operation at 1 V, BATT ON output for external PNP drive, and CEIN/CEOUT gating for CMOS RAM write lockout during supply faults.

Technical Context

The ADM8693ARUZ integrates a precision voltage monitor (4.40 V ±50 mV hysteresis), a three-level WDI input with internal 38% VCC bias and ~5 MΩ impedance, and dual oscillator control (internal or external capacitor/clock) enabling independent adjustment of reset pulse width (50 ms or adjustable) and watchdog timeout. Its battery switchover uses asymmetric thresholds (70 mV rise, 50 mV fall) with 20 mV hysteresis to prevent chatter during slow VCC decay.

It features separate logic outputs: active-low RESET, active-high LOW LINE, open-drain WDO, push-pull BATT ON, and gated CEOUT - all synchronized to VCC validity. The PFI comparator (1.30 V ±25 mV) drives PFO low on undervoltage, while CEIN-to-CEOUT gating enforces write disable when VCC drops below 4.40 V, ensuring data integrity in battery-backed RAM.

Key Specifications

Pinout & Package

ADM8693ARUZ is housed in a 16-lead TSSOP (RU-16) package with 0.65 mm pitch, optimized for high-density PCB layouts and industrial thermal performance (θJA = 158°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADM8691ARUZ, ADM8693ARUZ offers lower reset threshold (4.40 V vs. 4.65 V) for wider 5 V supply tolerance coverage, while MAX693ESA+ omits battery management and memory protection entirely - making ADM8693ARUZ the sole choice for systems requiring integrated RAM write lockout and dual-rail switchover.

Availability

ADM8693ARUZ is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, medical infusion pumps, and smart energy meters requiring stable component supply with guaranteed long-term lifecycle support.

Supply support for ADM8693ARUZ 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 microprocessor system integrity - integrating reset, watchdog, battery switchover, power-fail warning, and memory write protection into a single IC to eliminate discrete supervision complexity in space-constrained embedded designs.

FAQ

What is the guaranteed reset voltage threshold for ADM8693ARUZ?

The ADM8693ARUZ has a guaranteed reset voltage threshold of 4.25 V minimum to 4.48 V maximum, with a typical value of 4.40 V. This specification ensures reliable reset assertion across the full industrial temperature range (−40°C to +85°C) and matches 5 V ±10% power supplies. The 4.40 V threshold is factory-trimmed and tested per Analog Devices' Rev. B datasheet, Table 2.

Can ADM8693ARUZ operate with VCC as low as 1 V, and what does that mean for system reliability?

Yes, ADM8693ARUZ guarantees RESET output functionality down to VCC = 1 V, meaning it continues asserting reset to the microprocessor even during severe brownout or rapid power collapse. This prevents the MCU from executing random instructions or entering undefined states. The 1 V operation is validated per datasheet Figure 7 and ensures fail-safe shutdown in systems where backup capacitors sustain VCC just above 1 V for several milliseconds.

How does the battery switchover hysteresis work in ADM8693ARUZ, and why is it important?

ADM8693ARUZ uses asymmetric hysteresis: VOUT switches from VCC to VBATT when VCC falls to VBATT − 50 mV, and switches back when VCC rises to VBATT + 70 mV - yielding 20 mV total hysteresis. This prevents oscillatory switching during slow VCC decay near VBATT voltage, which could cause RAM corruption or logic glitches. The behavior is documented in the Battery Switchover Section (Page 10) and Figure 14 of the datasheet.

What are the exact pin functions of CEIN and CEOUT on ADM8693ARUZ, and how do they protect memory?

CEIN is the chip-enable input signal fed into the ADM8693ARUZ; CEOUT is its gated output. When VCC ≥ 4.40 V, CEOUT replicates CEIN with 3 ns delay. When VCC drops below threshold, CEOUT is forced high - disabling write access to battery-backed CMOS RAM. This hardware-enforced lockout prevents data corruption during power faults and is detailed in Figure 21 and the CE Gating section (Page 12) of the datasheet.

Is ADM8693ARUZ pin-compatible with other devices in the ADM869x family, and which ones share the same 16-lead TSSOP footprint?

Yes, ADM8693ARUZ is pin-compatible with ADM8691ARUZ and ADM8695ARUZ - all use the identical 16-lead TSSOP (RU-16) package and share identical pinout per Figure 4 and Table 4. Differences lie in reset threshold (4.40 V vs. 4.65 V vs. 4.65 V), reset timeout (50 ms vs. 50 ms vs. 200 ms), and watchdog configuration options - but PCB layout and interconnect remain unchanged across these variants.