Analog Devices Inc. ADM692AARN-REEL

Overview

ADM692AARN-REEL from Analog Devices is a precision microprocessor supervisory circuit in SO-8 package, providing 4.40 V reset threshold, 200 ms reset timeout, 1.6 s watchdog timer, and automatic battery switchover for CMOS RAM backup. It asserts active-low RESET down to 1 V VCC and monitors power fail via 1.25 V internal reference at PFI/PFO.

For engineers reviewing the ADM692AARN-REEL datasheet, ADM692AARN-REEL pinout, ADM692AARN-REEL application, or ADM692AARN-REEL equivalent, this device supports critical power sequencing, brownout recovery, watchdog supervision, and nonvolatile memory retention in industrial embedded systems requiring guaranteed reset assertion below 1 V.

Technical Context

The ADM692AARN-REEL integrates four core functions on a single die: a precision voltage monitor with 4.40 V ±0.15 V threshold, a monostable watchdog timer triggered by WDI transitions (1.6 s timeout), a battery switchover switch with <20 mV hysteresis and <1 Ω on-resistance, and a 1.25 V reference-based power fail comparator feeding PFO.

Its reset generator guarantees RESET low during power-up, brownout, and power-down - remaining functional even as VCC decays to 1 V - while the watchdog circuit disables automatically if WDI floats, enabling flexible software control without external components.

Key Specifications

Pinout & Package

ADM692AARN-REEL is housed in an 8-lead SOIC (SO-8) package per JEDEC MS-012, with 1.27 mm pitch, 5.0 mm × 6.2 mm body, and gull-wing leads. Pin 1 marked by notch or dot.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX692AESA+, ADM692AARN-REEL delivers lower quiescent current and guaranteed sub-1 V reset functionality; versus TPS3823-44DBVR, it integrates battery switchover and watchdog - reducing BOM count by two discrete ICs and simplifying layout.

Availability

ADM692AARN-REEL is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, and telecom infrastructure requiring stable component supply, long-lifecycle support, and guaranteed reset performance across –40°C to +85°C.

Supply support for ADM692AARN-REEL 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 ADM69x/ADM80x family was designed specifically for robust microprocessor supervision in harsh environments - integrating reset, watchdog, battery switchover, and power-fail detection into one SO-8 IC.

FAQ

What is the guaranteed minimum operating VCC for ADM692AARN-REEL reset assertion?

The ADM692AARN-REEL guarantees RESET assertion down to 1 V VCC, ensuring microprocessor hold during deep brownout conditions. This is confirmed in the Absolute Maximum Ratings and General Description sections of the datasheet, where RESET remains functional and asserted low even as VCC decays to 1 V - a key differentiator from many competing supervisors that require ≥2.5 V.

Does ADM692AARN-REEL support active-high reset output?

No, ADM692AARN-REEL provides only active-low RESET output. The active-high variant is the ADM805M series (e.g., ADM805MARN); ADM692AARN-REEL's RESET pin is push-pull active-low with 0.4 V max sink voltage at 3.2 mA, and no complementary RESET output is present on this part.

Can ADM692AARN-REEL monitor a 3.3 V supply using the PFI input?

Yes - the PFI input accepts any voltage referenced to GND and compares it against the internal 1.25 V reference. To monitor a 3.3 V rail, use a resistor divider (e.g., R1 = 16.5 kΩ, R2 = 10 kΩ) to scale 3.3 V down to 1.25 V at PFI. The datasheet specifies ±2% PFI accuracy for ADM692A, enabling precise trip-point setting.

What happens to VOUT when VBATT is disconnected and VCC is valid?

When VBATT is left unconnected (or tied to GND) and VCC is within specification (4.5–5.5 V), VOUT is internally connected to VCC through a low-R_DS(on) PMOS switch (<1 Ω). Output voltage remains VCC – 0.01 V typical at 5 mA load, per the Electrical Characteristics table - making VOUT suitable for powering CMOS RAM or other 5 V peripherals directly.

Is ADM692AARN-REEL pin-compatible with MAX692A?

Yes - ADM692AARN-REEL is a direct pin-compatible upgrade for MAX692A in SO-8 package, sharing identical pinout, reset threshold (4.40 V), timeout (200 ms), and functional block diagram. However, ADM692AARN-REEL offers lower quiescent current (100 µA vs. 120 µA) and guaranteed 1 V reset operation, which MAX692A does not specify.