Analog Devices Inc. ADM6320CX29ARJZ-R7

Overview

ADM6320CX29ARJZ-R7 from Analog Devices is a supervisory circuit with watchdog timer and manual reset, configured for 2.93 V reset threshold, 140 ms minimum reset timeout, and 102 ms typical watchdog timeout. It features open-drain active-low RESET output, operates from 1 V to 5.5 V supply, consumes ≤12 µA at 3.6 V, and is rated for −40°C to +85°C industrial temperature range. It is used in microprocessor-based embedded systems requiring reliable power-on reset and code execution monitoring.

For engineers reviewing the ADM6320CX29ARJZ-R7 datasheet, ADM6320CX29ARJZ-R7 pinout, ADM6320CX29ARJZ-R7 application, or ADM6320CX29ARJZ-R7 equivalent, key selection criteria include its open-drain RESET output compatibility with mixed-voltage logic interfaces, guaranteed reset validity down to VCC = 1 V, 100 ns MR glitch rejection, and SOT-23-5 footprint suitability for space-constrained portable and industrial controllers.

Technical Context

The ADM6320CX29ARJZ-R7 integrates a precision voltage reference, reset generator with hysteresis (3 mV), and watchdog detector with internal debounce. Its reset threshold is trimmed to 2.93 V ±2.5% over −40°C to +85°C, and reset timeout is guaranteed ≥140 ms (typical 200 ms) after VCC rises above threshold.

Watchdog functionality clears on any WDI logic transition (≥50 ns pulse width); timeout is 102 ms (min 71 ms, max 153 ms). Manual reset input (MR) includes 52 kΩ internal pull-up and asserts reset for ≥1 µs low pulse, with 230 ns propagation delay at VCC = 5 V.

Key Specifications

Pinout & Package

ADM6320CX29ARJZ-R7 is housed in a 5-lead SOT-23 package (JEDEC MO-178-AA compliant), with 1.3 mm × 2.9 mm footprint and 1.15 mm height. Pin 1 is RESET (open-drain active-low), Pin 2 is GND, Pin 3 is MR (active-low manual reset), Pin 4 is VCC (monitored supply), and Pin 5 is WDI (watchdog input).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6320XR29D3+T and TPS3808G33DBVR, ADM6320CX29ARJZ-R7 uniquely delivers integrated watchdog supervision, manual reset, and ultra-low 12 µA supply current in the same 5-lead SOT-23 package - making it the only option supporting full reset + watchdog + MR functionality with minimal footprint and power overhead.

Availability

ADM6320CX29ARJZ-R7 is available at Aetrix Electronics and suitable for industrial PLC controllers, medical handheld diagnostics, smart energy meters, and automotive body control modules requiring stable component supply and long-term lifecycle assurance.

Supply support for ADM6320CX29ARJZ-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, headquartered in Norwood, MA.

The ADM63xx family was designed specifically for robust microprocessor supervision in harsh industrial and portable environments, emphasizing low power, wide supply range, and glitch-immune reset generation.

FAQ

What is the exact reset threshold voltage of ADM6320CX29ARJZ-R7 and how does it vary with temperature?

The ADM6320CX29ARJZ-R7 has a nominal reset threshold of 2.93 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, resulting in a maximum deviation of approximately ±11.7 mV across the operating range. This ensures stable brownout detection in 3.3 V systems under thermal stress without requiring external calibration.

Does ADM6320CX29ARJZ-R7 require an external pull-up resistor on the RESET pin?

Yes, ADM6320CX29ARJZ-R7 requires an external pull-up resistor on the RESET pin because it features an open-drain active-low output. A 10 kΩ resistor to the target logic rail (≤6 V) is recommended to meet standard CMOS input thresholds while limiting current draw. The resistor value must be selected to ensure logic-high voltage compliance under worst-case sink current (≥1.2 mA at VCC ≥ 2.7 V) and leakage conditions.

Can ADM6320CX29ARJZ-R7 operate reliably when VCC drops below 1.5 V?

Yes, ADM6320CX29ARJZ-R7 guarantees valid reset assertion down to VCC = 1.0 V, as confirmed in the datasheet's specifications table. Its internal bandgap reference and reset generator remain functional at this level, ensuring deterministic reset behavior during deep brownout events. However, the external pull-up resistor must be sized appropriately to maintain logic-high voltage at the microcontroller input when VCC is near 1.0 V.

How is the watchdog timeout period configured on ADM6320CX29ARJZ-R7?

The watchdog timeout period on ADM6320CX29ARJZ-R7 is factory-configured and fixed per part number - in this case, "X" in the ordering code denotes 102 ms typical timeout (71–153 ms min–max). It cannot be adjusted externally; changing timeout requires selecting a different variant (e.g., "W" = 6.3 ms, "Y" = 1.6 s). The timer clears on any WDI logic transition and disables automatically when WDI is left floating.

What is the function of the MR pin on ADM6320CX29ARJZ-R7 and how should it be interfaced?

The MR pin on ADM6320CX29ARJZ-R7 is an active-low manual reset input with a built-in 52 kΩ pull-up resistor. To assert reset, drive MR to GND for ≥1 µs using a push-button switch or GPIO. Its 100 ns glitch rejection filters noise, and the 230 ns MR-to-RESET propagation delay (at VCC = 5 V) ensures predictable timing. No external pull-up is needed unless stronger immunity or faster rise time is required.