Analog Devices Inc. ADM8699ARW

Overview

ADM8699ARW from Analog Devices is a microprocessor supervisory circuit with integrated watchdog timer, precision 4.65 V voltage monitor, and guaranteed RESET assertion down to VCC = 1 V. It provides power-up/down reset, brown-out protection, and 1.6 s typical watchdog timeout for embedded microprocessor systems requiring high-reliability power monitoring.

For engineers reviewing the ADM8699ARW datasheet, ADM8699ARW pinout, ADM8699ARW application, or ADM8699ARW equivalent, key selection criteria include its 16-lead SOIC package with dual RESET outputs (active-low RESET and active-high RESET), WDO status flag, WDI three-level watchdog input, and industrial temperature range (–40°C to +85°C).

Technical Context

The ADM8699ARW implements a precision bandgap-based voltage detector with 40 mV hysteresis and a monostable power-on reset timer delivering ≥140 ms active-low RESET pulse. Its watchdog transition detector monitors WDI toggling and triggers RESET if no edge occurs within 1.0–2.25 s.

Unlike the ADM8698, the ADM8699ARW includes dedicated WDI and WDO pins in its 16-lead SOIC footprint, enabling real-time watchdog status feedback and software execution verification without external logic. The active-high RESET output supports µPs requiring non-inverted reset signaling.

Key Specifications

Pinout & Package

ADM8699ARW is housed in a 16-lead SOIC package (R-16), measuring 10.50 mm × 7.60 mm × 2.65 mm, with standard 1.27 mm pitch and gull-wing leads. Pin 1 marked with dot; pin 1–8 on top row, pin 9–16 on bottom row (left-to-right, top-to-bottom).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX699CSA+ and TPS3823DBVR, the ADM8699ARW uniquely delivers integrated watchdog status (WDO), dual-polarity RESET outputs, and guaranteed sub-1.5 V operation - making it optimal for safety-critical, diagnostics-aware µP systems where both power integrity and software liveness must be independently verified.

Availability

ADM8699ARW is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, and medical infusion pumps requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for ADM8699ARW 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 ADM8698/ADM8699 family was designed specifically for robust microprocessor supervision in harsh environments - emphasizing guaranteed low-voltage reset, watchdog reliability, and minimal external component count for mission-critical embedded systems.

FAQ

What is the function of the WDO pin on the ADM8699ARW?

The WDO (Watchdog Output) pin on the ADM8699ARW is an active-low status indicator that goes low whenever the WDI input fails to toggle within the watchdog timeout period (1.0–2.25 s). It returns high on the next WDI transition or when VCC falls below the reset threshold. This pin enables external monitoring of watchdog activity without polling, supporting diagnostic logging and fail-safe escalation in systems using the ADM8699ARW.

Can the ADM8699ARW operate with a 3.3 V supply?

No - the ADM8699ARW is specified for VCC = 3.0 V to 5.5 V, but its reset threshold is fixed at 4.65 V. Using it with a 3.3 V supply will cause continuous RESET assertion because VCC remains below threshold. It is intended exclusively for 5 V systems. For 3.3 V supervision, consider alternatives like the ADM809 or TPS3809, not the ADM8699ARW.

How does the ADM8699ARW handle watchdog disable?

The ADM8699ARW watchdog is disabled when the WDI pin is left floating or biased to midsupply (~2.5 V), leveraging its three-level input architecture. No external resistor or configuration register is needed. This behavior is explicitly documented in the datasheet and applies to the ADM8699ARW without modification - allowing simple hardware-based enable/disable control.

What is the significance of the dual RESET outputs on the ADM8699ARW?

The ADM8699ARW provides both active-low RESET and active-high RESET outputs in its 16-lead SOIC package. This eliminates the need for external inverters when interfacing with µPs requiring opposite reset polarities - for example, legacy 8051 derivatives (active-low) and newer ARM Cortex-M devices (often active-high). Both outputs are synchronized and guaranteed functional down to VCC = 1 V, enhancing design flexibility and reducing BOM count.

Is the ADM8699ARW pin-compatible with the ADM8698ARW?

No - while both use the 16-lead SOIC (R-16) package, the ADM8699ARW and ADM8698ARW have different pin assignments. The ADM8699ARW allocates Pin 14 to WDI and Pin 16 to WDO, whereas the ADM8698ARW uses those pins as NC. Substituting them requires PCB layout changes; they are functionally related but not pin-compatible replacements.