Analog Devices Inc. ADM8320WCZ29ARJZR7

Overview

ADM8320WCZ29ARJZR7 from Analog Devices is a supervisory circuit with watchdog timer and manual reset, designed for microprocessor supply voltage monitoring in automotive and industrial systems. It features a 2.93 V reset threshold, 140 ms minimum reset timeout, 25.6 sec typical watchdog timeout, open-drain active-low RESET output, and operates across −40°C to +125°C.

For engineers reviewing the ADM8320WCZ29ARJZR7 datasheet, ADM8320WCZ29ARJZR7 pinout, ADM8320WCZ29ARJZR7 application, or ADM8320WCZ29ARJZR7 equivalent, this device supports robust power-on reset, brownout detection, code execution integrity monitoring via watchdog, and push-button-initiated system recovery in safety-critical embedded environments.

Technical Context

The ADM8320WCZ29ARJZR7 implements an on-chip voltage monitor with factory-trimmed 2.93 V threshold (±1.5% over temperature), a programmable watchdog timer cleared by logic transitions on WDI, and glitch-filtered manual reset input with 75 kΩ internal pull-up. Its open-drain RESET output requires an external pull-up resistor and remains valid down to VCC = 0.9 V.

It integrates undervoltage detection, fixed reset timeout delay after VCC rise, and watchdog timeout assertion if WDI remains static beyond 25.6 sec (typical). The device disables watchdog when WDI is floating and supports noise-immune MR pulse widths as short as 1 µs with 100 ns glitch rejection.

Key Specifications

Pinout & Package

ADM8320WCZ29ARJZR7 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 matte tin finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADM8320WCY29ARJZR7 and TPS3808G33DBVR, ADM8320WCZ29ARJZR7 uniquely delivers long-interval watchdog supervision (25.6 sec) alongside manual reset and automotive qualification-making it optimal for complex embedded systems requiring both safety-critical startup assurance and extended runtime fault detection.

Availability

ADM8320WCZ29ARJZR7 is available at Aetrix Electronics and suitable for automotive infotainment, engine control units, and ADAS camera modules requiring stable component supply, AEC-Q100 compliance, and long watchdog supervision intervals.

Supply support for ADM8320WCZ29ARJZR7 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 Wilmington, MA.

The ADM83xx family is engineered specifically for automotive and industrial microprocessor supervision, delivering precision voltage monitoring, configurable watchdog timing, and robust reset generation under extreme thermal and electrical stress.

FAQ

What is the exact reset threshold voltage of ADM8320WCZ29ARJZR7 and how does it vary with temperature?

The ADM8320WCZ29ARJZR7 has a nominal reset threshold of 2.93 V at 25°C, with guaranteed tolerance of ±1.5% over the full operating range of −40°C to +125°C. Its temperature coefficient is 20 ppm/°C, resulting in maximum deviation of approximately ±14.65 mV across the temperature range. This precision enables reliable brownout detection in 3.3 V systems with tight LDO dropout margins.

Does ADM8320WCZ29ARJZR7 support manual reset, and what are its electrical characteristics?

Yes, ADM8320WCZ29ARJZR7 includes an active-low manual reset (MR) input with a 75 kΩ internal pull-up resistor. It accepts logic-low pulses as short as 1 µs and rejects glitches up to 100 ns. The input thresholds are VIL ≤ 0.8 V and VIH ≥ 2.0 V at VCC = 5 V. This allows direct connection to push-button switches without external components while maintaining noise immunity in electrically noisy automotive environments.

What is the watchdog timeout behavior of ADM8320WCZ29ARJZR7, and how is it cleared?

The ADM8320WCZ29ARJZR7 provides a typical watchdog timeout of 25.6 sec (suffix Z), cleared by any logic transition (low-to-high or high-to-low) on the WDI pin. Pulses as narrow as 50 ns are recognized. If WDI remains static beyond the timeout, RESET is asserted. The timer also clears automatically upon any reset event (VCC undervoltage or MR activation), preventing spurious timeouts during power recovery sequences.

How does the open-drain RESET output of ADM8320WCZ29ARJZR7 function, and what pull-up value is recommended?

The ADM8320WCZ29ARJZR7 features an active-low open-drain RESET output requiring an external pull-up resistor to a voltage rail ≤ VCC. A 10 kΩ resistor is recommended for most applications, ensuring VOL ≤ 0.3 V at ISINK = 3.2 mA (VCC ≥ 4.5 V) while meeting microprocessor input logic-high requirements. This configuration supports wired-OR reset buses and level translation between different voltage domains.

Is ADM8320WCZ29ARJZR7 qualified for automotive use, and what does the 'W' suffix indicate?

Yes, ADM8320WCZ29ARJZR7 is qualified for automotive applications-the 'W' in the part number denotes AEC-Q100 Grade 1 qualification (−40°C to +125°C) with controlled manufacturing and enhanced reliability testing. It meets stringent automotive requirements for thermal cycling, humidity resistance, and long-term operational stability, making it suitable for under-hood and infotainment systems where functional safety and field longevity are critical.