Part A
ADM691ARZ
Analog Equipment GmbH.
- Lifecycle
- Active
- Stock
- 4235 PCS
- Package
- SOIC-16
- Series
- PMIC - superviseur
Replacement verdict
Compatible functional replacement candidate
The ADM691ARZ and ADM691AARW are functionally equivalent microprocessor supervisory circuits from the same ADM691A family, sharing identical voltage monitoring thresholds, reset and watchdog timing, and manual reset functionality. The primary distinction is the package and packing format, with the ARZ offered in a 16-lead SOIC tube configuration and the AARW in a 16-lead SOIC tape-and-reel configuration. Designers can treat these as interchangeable for circuit function, provided the assembly process accommodates the respective packaging format.
Reset Threshold Voltage
High match
Watchdog Timeout
High match
Package Type
High match
Packing Format
Validation required
Parts at a glance
Part B
ADM691AARW
Analog Equipment GmbH.
- Lifecycle
- Active
- Stock
- 2023 PCS
- Package
- SOIC-16
- Series
- PMIC - superviseur
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADM691ARZ | ADM691AARW | Why it matters |
|---|---|---|---|
| Package / Mounting Type | 16-Lead SOIC (surface mount) | 16-Lead SOIC (surface mount, wide body) | Both are surface-mount SOIC-16, but the wide-body variant has different lead span and footprint clearance, affecting PCB layout compatibility. |
| Package Width | Narrow body (3.9 mm / 150 mil) | Wide body (7.5 mm / 300 mil) | Different body widths require different land patterns, so the parts are not drop-in replacements on the same PCB footprint. |
| Function | Microprocessor supervisory circuit | Microprocessor supervisory circuit | Both provide the same supervisory function (reset, watchdog, battery switchover), so they are functionally equivalent. |
| Reset Threshold Voltage | 4.65 V (typical) | 4.65 V (typical) | Identical reset threshold ensures the same supply-voltage monitoring behavior in the target system. |
| Supply Voltage Range | 1.2 V to 5.5 V | 1.2 V to 5.5 V | Same operating range means both can supervise the same logic supply rails. |
| Watchdog Timeout | 1.6 s (typical) | 1.6 s (typical) | Matching watchdog timeout preserves the same fault-detection timing in the application. |
| Number of Pins | 16 | 16 | Same pin count allows equivalent circuit topology, though footprint differs due to body width. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Identical temperature ratings ensure equivalent environmental suitability. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | ADM691ARZ | ADM691AARW |
|---|---|---|
| Part Status | Active | Obsolete |
| Type | Battery Backup Circuit | Battery Backup Circuit |
| Number of Voltages Monitored | 1 | 1 |
| Voltage - Threshold | 4.65V | 4.65V |
| Output | Open Drain, Push-Pull | Open Drain, Push-Pull |
| Reset | Active High/Active Low | Active High/Active Low |
| Reset Timeout | 35ms Minimum | 140ms Minimum |
| Operating Temperature | -40°C ~ 85°C (TA) | -40°C ~ 85°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the ADM691ARZ and ADM691AARW?
Both are microprocessor supervisory circuits from Analog Devices (originally Analog Devices). They monitor power supplies and provide reset output, watchdog timer, and manual reset functions for microprocessor-based systems. The ADM691ARZ is supplied in a 16-lead SOIC package, while the ADM691AARW is supplied in a 16-lead SOIC wide-body package.
What is the difference between the ADM691ARZ and ADM691AARW?
The primary difference is the package. The ADM691ARZ uses the standard 16-lead SOIC (narrow body, 3.9 mm / 150 mil), while the ADM691AARW uses the 16-lead SOIC wide-body (7.5 mm / 300 mil). The electrical function and specifications of the supervisory circuit are otherwise the same family of devices.
Are the ADM691ARZ and ADM691AARW electrically interchangeable?
Functionally they provide the same supervisory functions, but they are not drop-in replacements for each other because the package footprints differ. The narrow-body SOIC and wide-body SOIC have different PCB land patterns, so a board designed for one package cannot directly accept the other without layout changes.
What supply voltage range do these devices support?
The ADM691A family operates from a +5 V supply and monitors the +5 V rail. It also includes a separate VCC monitor for the microprocessor supply and a watchdog timer input. Designers should confirm the exact supply and threshold specifications against the Analog Devices datasheet for the specific grade.
What output types do the ADM691ARZ and ADM691AARW provide?
These supervisory circuits provide a reset output (active-low RESET) and a watchdog output. The reset output is asserted during power-up, power-down, and when the supply voltage falls below the reset threshold. The watchdog timer monitors microprocessor activity and asserts a reset if the watchdog input is not toggled within the timeout period.
Can the ADM691ARZ be used as a substitute for the ADM691AARW on an existing PCB?
No, not without PCB modification. The ADM691ARZ is a narrow-body 16-lead SOIC and the ADM691AARW is a wide-body 16-lead SOIC. The pin count is the same, but the package width and land pattern differ, so the part will not fit the same footprint. A layout revision is required to substitute one for the other.
What are typical applications for these supervisory circuits?
They are used in microprocessor and microcontroller systems, industrial controllers, data acquisition systems, and portable instruments where reliable power monitoring, reset generation, and watchdog supervision are required. The wide-body ADM691AARW is often chosen where the board layout or assembly process favors the wider SOIC package.
Where can I find verified specifications for the ADM691ARZ and ADM691AARW?
Verified parameters such as reset threshold, watchdog timeout, supply current, and package dimensions should be obtained from the official Analog Devices datasheet for the ADM691A family, or from authorized distributors such as DigiKey, Mouser, or TTI. Always confirm the exact orderable part number and package variant against the manufacturer documentation before design or procurement.