Analog Devices Inc. ADM699ARZ

Overview

ADM699ARZ 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 detection, and 1.6 s typical watchdog timeout for embedded microprocessor systems requiring reliable system initialization and software fault recovery.

For engineers reviewing the ADM699ARZ datasheet, ADM699ARZ pinout, ADM699ARZ application, or ADM699ARZ equivalent, this page delivers verified functional identity, SOIC-16 package mapping, confirmed WDI/WDO/RESET pin roles, real-world timing behavior (140–280 ms reset active time, 1.0–2.25 s watchdog timeout), and validated alternatives for critical mP power monitoring designs.

Technical Context

The ADM699ARZ implements a precision bandgap-based voltage detector with 40 mV hysteresis and an internal monostable for 140–280 ms reset pulse generation. Its watchdog transition detector responds to rising/falling edges on WDI and resets the 1.6 s timeout period on each valid toggle.

This device operates over –40°C to +85°C, draws only 0.6–1.95 mA supply current, and guarantees functional RESET output down to VCC = 1 V - enabling stable processor hold during deep undervoltage conditions. The SOIC-16 package supports both active-low RESET* and active-high RESET outputs plus dedicated WDO status signaling.

Key Specifications

Pinout & Package

ADM699ARZ is supplied in a 16-lead SOIC (R-16) package with 1.27 mm pitch, 10.3 mm × 7.5 mm body, and thermal impedance θJA = 110°C/W. Pin functions are validated per Analog Devices ADM698/ADM699 Rev. 0 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX699CSA+ and TPS3808G33DBVR, the ADM699ARZ uniquely combines 5 V precision monitoring, guaranteed sub-1 V reset operation, and integrated watchdog with dual-reset outputs - making it irreplaceable in safety-critical 5 V microprocessor systems requiring both power and software fault coverage.

Availability

ADM699ARZ is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive engine control units, and medical infusion pumps requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADM699ARZ 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 ADM698/ADM699 family was engineered specifically for robust microprocessor power supervision in harsh environments - delivering guaranteed reset behavior, low quiescent current, and integrated watchdog timing without external components.

FAQ

What is the function of the WDI pin on the ADM699ARZ?

The WDI (Watchdog Input) pin on the ADM699ARZ monitors microprocessor activity via transitions - each rising or falling edge resets the 1.6 s watchdog timeout. If WDI remains static beyond that period, ADM699ARZ asserts RESET* and pulls WDO low. WDI accepts three logic states: low (≤0.8 V), high (≥3.5 V), or floating/midsupply (disables watchdog). This behavior is explicitly defined in the ADM699ARZ datasheet Section "PIN FUNCTION DESCRIPTION" and confirmed in the Typical Application Circuit.

Does the ADM699ARZ support 3.3 V systems?

No, the ADM699ARZ is specified for 3.0 V to 5.5 V operation but features a fixed 4.65 V reset threshold optimized for 5 V systems. Its WDI input thresholds (0.8 V low, 3.5 V high) and RESET output drive strength are calibrated for 5 V logic compatibility. Using ADM699ARZ in a 3.3 V system risks unreliable reset assertion and invalid watchdog triggering - Analog Devices does not characterize or guarantee performance below 4.5 V VCC for reset functionality.

What is the difference between RESET* and RESET pins on the ADM699ARZ?

On the ADM699ARZ SOIC-16 package, RESET* is the active-low reset output (logic low during reset), while RESET is the active-high complement (logic high during reset). Both are simultaneously asserted - RESET is the inverse of RESET*. This dual-output architecture eliminates external inverters when interfacing with microprocessors requiring either polarity, and is exclusive to the 16-lead SOIC variant per the ADM699ARZ datasheet Pin Configuration diagram and Function Description table.

Can the ADM699ARZ watchdog be disabled?

Yes, the ADM699ARZ watchdog can be disabled by leaving the WDI pin floating or driving it to approximately midsupply (~2.5 V). The datasheet confirms WDI is a three-level input: low, high, or mid-level. When held at midsupply or unconnected, the internal watchdog transition detector is inactive, WDO remains high, and only power-related reset events (power-up, brown-out) trigger RESET*. No external resistor or configuration register is required - disable behavior is inherent to the ADM699ARZ analog input design.

What is the thermal performance of the ADM699ARZ in SOIC-16 package?

The ADM699ARZ in SOIC-16 (R-16) package has a junction-to-ambient thermal resistance (θJA) of 110°C/W and a maximum power dissipation of 375 mW. At its maximum specified supply current of 1.95 mA and 5.5 V VCC, power dissipation remains under 11 mW - well within thermal limits even at +85°C ambient. This margin ensures stable operation without heatsinking in standard industrial PCB layouts, as verified in the Absolute Maximum Ratings and Thermal Impedance specifications of the ADM699ARZ datasheet.