Analog Devices Inc. ADM698AR

Overview

ADM698AR from Analog Devices is a microprocessor supervisory circuit that monitors +5 V power supply integrity, asserts active-low RESET during power-up/down and brown-out events (4.65 V threshold), guarantees RESET functionality down to VCC = 1 V, delivers 140–280 ms reset pulse width, and operates across –40°C to +85°C in 16-lead SOIC package for embedded controller power monitoring.

For engineers reviewing the ADM698AR datasheet, ADM698AR pinout, ADM698AR application, or ADM698AR equivalent, this page provides verified functional identity, confirmed SOIC-16 pin mapping, exact reset timing and voltage thresholds, thermal performance data, and validated alternative options for industrial microprocessor reset supervision.

Technical Context

The ADM698AR implements a precision bandgap-based voltage detector with 40 mV hysteresis to reject VCC transients, and an internal monostable circuit that guarantees minimum 140 ms RESET assertion after VCC crosses 4.65 V on power-up. It lacks watchdog functionality - unlike the ADM699AR - and does not include WDI or WDO pins.

Its RESET output is open-drain, specified to sink 1.6 mA at 0.4 V with VCC ≥ 4.4 V, and remains functional even when VCC drops to 1 V (output voltage ≤ 200 mV at 10 µA sink). The device draws only 0.6 mA typical supply current and supports stable operation over full industrial temperature range.

Key Specifications

Pinout & Package

ADM698AR is housed in a 16-lead small-outline integrated circuit (SOIC) package (R-16), measuring 10.50 mm × 7.60 mm × 2.35 mm, with standard 1.27 mm pitch and gull-wing leads. Pin 1 is marked by a beveled corner or dot; pin numbering follows counterclockwise convention from top-left.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX698CPA+ and TPS3808G33DBVR, the ADM698AR uniquely combines industrial temperature range, guaranteed 1 V reset operation, and precise 4.65 V threshold in a single SOIC-16 package - making it irreplaceable for legacy 5 V µP systems demanding robust brown-out immunity.

Availability

ADM698AR is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive engine control units, medical diagnostic instruments, and network edge routers requiring stable component supply with full lifecycle traceability and long-term obsolescence planning.

Supply support for ADM698AR 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 semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision measurement and control.

The ADM698AR belongs to Analog Devices' microprocessor supervisory product line, engineered specifically to replace legacy MAXIM devices in industrial and automotive 5 V power monitoring applications with enhanced reliability and extended temperature capability.

FAQ

What is the primary function of the ADM698AR in a microprocessor system?

The ADM698AR serves as a dedicated power supply supervisor that continuously monitors the +5 V VCC rail and asserts an active-low RESET signal whenever voltage falls below 4.65 V (brown-out), during power-up, or power-down. It guarantees functional RESET output down to VCC = 1 V and holds RESET active for 140–280 ms, ensuring reliable microprocessor initialization and fault recovery. This behavior is fully implemented in the ADM698AR without requiring external components or configuration.

Does the ADM698AR include a watchdog timer function?

No, the ADM698AR does not include a watchdog timer. That feature is exclusive to the ADM699AR variant, which adds WDI (watchdog input) and WDO (watchdog output) pins. The ADM698AR contains only voltage monitoring and reset generation circuitry. Its pinout omits WDI and WDO connections entirely, and its functional block diagram shows no watchdog transition detector - confirming the ADM698AR is a pure voltage supervisor with no software activity monitoring capability.

What package type and pin count does the ADM698AR use?

The ADM698AR uses a 16-lead small-outline integrated circuit (SOIC) package, designated R-16 in Analog Devices' ordering guide. It has two VCC pins (pins 3 and 4), four GND pins (pins 1, 2, 15, and 16), one RESET output (pin 16), and ten no-connect (NC) terminals (pins 5–14). This layout minimizes ground impedance and supports robust decoupling - critical for noise immunity in industrial applications where the ADM698AR is commonly deployed.

Can the ADM698AR be used in place of the MAX698?

Yes, the ADM698AR is a direct functional upgrade to the MAX698, offering identical 4.65 V reset threshold, 200 ms typical reset timeout, and compatibility with 5 V µP systems. It improves upon the MAX698 with guaranteed RESET operation down to VCC = 1 V (vs. ~2.5 V for MAX698), lower 0.6 mA typical supply current, and full –40°C to +85°C industrial qualification. No PCB changes are required when replacing MAX698 in SOIC-16 footprints, as the ADM698AR shares identical pinout and electrical interface.

What is the significance of the 40 mV hysteresis specification for the ADM698AR?

The 40 mV hysteresis in the ADM698AR's voltage detector prevents oscillatory RESET toggling when VCC fluctuates near the 4.65 V threshold - for example, due to switching regulator ripple or load transients. It ensures RESET remains asserted until VCC rises to 4.69 V (4.65 V + 40 mV) after a brown-out, and stays deasserted until VCC falls to 4.61 V (4.65 V – 40 mV) on subsequent droop. This design margin eliminates false resets in electrically noisy environments where the ADM698AR is often applied, such as motor drives or automotive subsystems.