Analog Devices Inc. ADM8697ARW-REEL

Overview

ADM8697ARW-REEL from Analog Devices is a microprocessor supervisory circuit with integrated chip-enable gating, reset generation, watchdog timer, and low-line monitoring. It features 50 ms reset timeout, 1.6 s/100 ms selectable watchdog periods, 1.3 V LLIN threshold, CEIN-to-CEOUT propagation delay of 2–7 ns, and operates from 3.0 V to 5.5 V VCC. It is used in embedded controllers for RAM write protection during brownout.

For engineers reviewing the ADM8697ARW-REEL datasheet, ADM8697ARW-REEL pinout, ADM8697ARW-REEL application, or ADM8697ARW-REEL equivalent, key selection criteria include CE gating speed, battery-independent reset assertion down to 1 V VCC, adjustable watchdog timing via OSC SEL/OSC IN, and guaranteed operation over –40°C to +85°C industrial temperature range.

Technical Context

The ADM8697ARW-REEL implements dual-mode oscillator control (internal 10.24 kHz or external clock/capacitor) to configure both reset pulse width and watchdog timeout independently. Its CE gating logic forces CEOUT high when LLIN falls below 1.3 V, blocking memory writes regardless of CEIN state.

It integrates a precision 1.3 V bandgap reference for LLIN, PFI, and internal comparators, with 12 mV hysteresis on LLIN for noise immunity. The device enters battery-backup mode only when VCC drops below VBATT − 0.2 V, but CEIN/CEOUT remain functional and actively gated even during backup.

Key Specifications

Pinout & Package

ADM8697ARW-REEL is housed in a 16-pin SOIC (R-16) package with 1.27 mm pitch, JEDEC MS-012AC compliant, and rated for θ_JA = 110°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX697CPE+ and TPS3823DBVR, the ADM8697ARW-REEL uniquely delivers nanosecond-precision CE gating synchronized to supply monitoring-enabling hardware-enforced RAM write blocking that neither alternative supports.

Availability

ADM8697ARW-REEL is available at Aetrix Electronics and suitable for industrial controllers, automotive body electronics, medical devices, point-of-sale terminals, and critical µP power monitoring requiring stable component supply across extended temperature and long lifecycle programs.

Supply support for ADM8697ARW-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 instrumentation, industrial, and automotive markets.

The ADM8697ARW-REEL belongs to Analog Devices' microprocessor supervisory IC product line, designed specifically to ensure data integrity and deterministic restart in systems with battery-backed memory and safety-critical power sequencing requirements.

FAQ

What is the minimum VCC voltage at which ADM8697ARW-REEL guarantees RESET assertion?

The ADM8697ARW-REEL guarantees RESET assertion down to 1 V VCC, as confirmed in the Absolute Maximum Ratings and General Description sections. This ensures the microprocessor remains held in reset during severe brownout conditions where other supervisors may release prematurely. The RESET output remains functional and valid even at this low voltage, with specified sink current capability of 10 µA at VCC = 1 V.

How does ADM8697ARW-REEL implement chip-enable gating, and what is its propagation delay?

The ADM8697ARW-REEL implements chip-enable gating by routing CEIN through an internal logic gate whose enable is controlled by the LLIN comparator output. When LLIN falls below 1.3 V, CEOUT is forced high regardless of CEIN state. The CE propagation delay is 2–7 ns at VCC = 5.0 V and 4 ns at VCC = 3.0 V, enabling real-time write blocking without violating memory timing budgets. This behavior is documented in the Pin Function Description and Typical Applications sections.

Can ADM8697ARW-REEL operate with a 3.3 V supply, and what are the key thresholds at that voltage?

Yes, ADM8697ARW-REEL operates across 3.0 V to 5.5 V VCC, including 3.3 V nominal systems. At 3.3 V, the LLIN and PFI thresholds remain centered at 1.3 V (±50 mV), CEIN logic thresholds are VIL = 0.8 V and VIH = 1.2 V, and CEOUT output high voltage is ≥2.7 V at 1 µA source current. All timing parameters-including 50 ms reset delay and 100 ms/1.6 s watchdog periods-remain fully specified and validated per the datasheet Electrical Characteristics table.

What is the function of the TEST pin on ADM8697ARW-REEL, and how should it be connected?

The TEST pin (Pin 1) on ADM8697ARW-REEL is a dedicated manufacturing test node with no user-accessible function. Per the Pin Function Description, it must be connected to GND in all application circuits. Leaving it floating or connecting it to any other potential may compromise device reliability or cause undefined behavior, as it is not electrically isolated from internal test structures during normal operation.

Does ADM8697ARW-REEL support external timing components, and how is watchdog timeout adjusted?

Yes, ADM8697ARW-REEL supports external timing via OSC IN and OSC SEL. With OSC SEL low, OSC IN accepts either an external clock (0–500 kHz) or a capacitor (e.g., 47 pF to ground) to set both reset delay and watchdog timeout. For example, a 47 pF capacitor yields ~1.6 s watchdog timeout; scaling C changes timing linearly per F_OSC = 184,000/C(pF). This configuration is detailed in Table I and Figure 4b of the datasheet.