Analog Devices Inc. ADM6318BX49ARJZ-R7

Overview

ADM6318BX49ARJZ-R7 from Analog Devices is a supervisory circuit with integrated watchdog timer and dual active-low/active-high push-pull reset outputs, designed for microprocessor supply voltage monitoring. It features a 4.9 V reset threshold (±2.5% over −40°C to +85°C), 20 ms minimum reset timeout, and 102 ms typical watchdog timeout. Used in embedded controllers where reliable power-on reset and code execution integrity are critical.

For engineers reviewing the ADM6318BX49ARJZ-R7 datasheet, ADM6318BX49ARJZ-R7 pinout, ADM6318BX49ARJZ-R7 application, or ADM6318BX49ARJZ-R7 equivalent, this device delivers verified brownout detection down to VCC = 1 V, glitch-immune reset assertion, and watchdog pulse validation at 50 ns minimum width - key selection criteria for industrial microcontroller systems requiring robust fault recovery.

Technical Context

The ADM6318BX49ARJZ-R7 implements a precision bandgap-based voltage reference for reset threshold detection with 40 ppm/°C temperature coefficient and 3 mV hysteresis. Its watchdog timer clears on any WDI logic transition and supports four timeout options; this part uses the 102 ms typical option (suffix X).

This variant lacks manual reset input (MR) but provides dual push-pull RESET outputs: one active-low and one active-high, both guaranteed functional down to VCC = 1 V. The device draws only 5–12 µA across its 1 V to 5.5 V operating range and operates over the full industrial temperature range (−40°C to +85°C).

Key Specifications

Pinout & Package

ADM6318BX49ARJZ-R7 is housed in a 5-lead SOT-23 (RJ-5) package, measuring 2.9 mm × 1.6 mm × 1.1 mm, with gull-wing leads and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADM6318BX49ARJZ-R7, MAX6326UT49D3+ offers lower cost but sacrifices dual-output flexibility and watchdog capability, while TPS3808G33DBVR provides higher accuracy at 3.3 V but cannot monitor 4.9 V rails or enforce runtime firmware integrity.

Availability

ADM6318BX49ARJZ-R7 is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic handhelds, automotive body control modules, and smart energy meters requiring stable component supply across extended production lifecycles.

Supply support for ADM6318BX49ARJZ-R7 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, Inc. 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 ADM6318 is part of Analog Devices' supervisory circuits product line, engineered specifically for microprocessor-based systems needing precise voltage monitoring, deterministic reset timing, and watchdog-enforced firmware reliability in harsh environments.

FAQ

What is the exact reset threshold voltage of ADM6318BX49ARJZ-R7 and how does it vary with temperature?

The ADM6318BX49ARJZ-R7 has a nominal reset threshold of 4.90 V at 25°C, with tolerance of ±2.5% over the full industrial temperature range (−40°C to +85°C). Its temperature coefficient is 40 ppm/°C, meaning the threshold drifts by approximately ±0.0049 V across the entire range - confirmed in Table 5 of the Rev. K datasheet. This ensures consistent brownout detection in thermally variable environments without calibration.

Does ADM6318BX49ARJZ-R7 include a manual reset input (MR) pin?

No, ADM6318BX49ARJZ-R7 does not feature a manual reset input. Per Table 1 and Pin Function Descriptions (page 6), the ADM6318 variant excludes MR functionality - Pin 3 is designated as the active-high RESET output, not MR. This distinguishes it from ADM6316 and ADM6319, which include MR. Designers requiring push-button reset must select an alternate part or add external logic.

What are the electrical characteristics of the dual reset outputs on ADM6318BX49ARJZ-R7?

ADM6318BX49ARJZ-R7 provides two independent push-pull outputs: Pin 1 (active-low RESET) sinks up to 1.2 mA at VCC ≥ 2.7 V with VOH ≤ 0.3 V, and Pin 3 (active-high RESET) sources up to 500 µA at VCC ≥ 2.7 V with VOL ≥ 0.8 × VCC. Both outputs remain valid down to VCC = 1 V, enabling robust reset signaling during deep brownout - verified in the "Push-Pull Output" section of Table 2.

How is the watchdog timeout configured on ADM6318BX49ARJZ-R7, and what is its typical value?

The watchdog timeout on ADM6318BX49ARJZ-R7 is factory-configured to 102 ms (typical), corresponding to suffix "X" per Table 7. It clears on any logic transition (≥50 ns wide) at the WDI pin (Pin 4) and asserts reset if no transition occurs within the timeout window. This value is fixed for this part number and cannot be adjusted externally - confirmed in the Ordering Guide and Table 9.

Is ADM6318BX49ARJZ-R7 compatible with 3.3 V microcontrollers despite its 4.9 V reset threshold?

Yes, ADM6318BX49ARJZ-R7 is fully compatible with 3.3 V microcontrollers. Its 4.9 V threshold monitors a separate 5 V supply rail (e.g., VCC_IO or auxiliary power), while its dual push-pull outputs operate from that same 5 V rail and interface directly with 3.3 V-tolerant MCU reset inputs. The device's VCC pin accepts 1 V to 5.5 V, and output logic levels meet standard CMOS thresholds - validated in the "Push-Pull Output" specifications (Table 2).