Analog Devices Inc. ADM823ZYKSZ-R7

Overview

ADM823ZYKSZ-R7 from Analog Devices is a precision supervisory circuit with watchdog timer and manual reset, designed for microprocessor supply voltage monitoring in automotive-grade systems. It features a 2.32 V reset threshold (±0.07 V), 140 ms minimum reset timeout, 1.6 sec typical watchdog timeout, push-pull active-low RESET output, and operates across −40°C to +125°C. It is used in engine control units to ensure reliable boot-up and runtime fault recovery.

For engineers reviewing the ADM823ZYKSZ-R7 datasheet, ADM823ZYKSZ-R7 pinout, ADM823ZYKSZ-R7 application, or ADM823ZYKSZ-R7 equivalent, key selection criteria include reset threshold accuracy at low VCC, guaranteed reset validity down to 1 V, integrated MR debounce, SC70 package footprint constraints, and watchdog pulse timing compliance with ISO 26262 diagnostic requirements.

Technical Context

The ADM823ZYKSZ-R7 implements a precision bandgap-based reset comparator with 40 ppm/°C temperature coefficient and 5 mV hysteresis, ensuring stable trip point over automotive temperature extremes. Its watchdog detector clears on any WDI logic transition ≥50 ns and times out after 1.6 sec if unserviced - a fixed internal RC-based timeout not software-programmable.

It integrates an internal 52 kΩ MR pull-up resistor and on-chip debounce circuitry that rejects <100 ns glitches on the manual reset input. The push-pull RESET output guarantees logic-low state down to VCC = 1 V with 3.2 mA sink capability at VTH min, enabling direct interface with 1.8 V/3.3 V microcontrollers without external level-shifting.

Key Specifications

Pinout & Package

ADM823ZYKSZ-R7 is housed in a 5-lead SC70 (KS-5) package, 2.0 mm × 1.25 mm × 0.9 mm, JEDEC MO-203-AA compliant, optimized for space-constrained automotive PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS3808G125DBVR and MAX6326UT23D3+T, the ADM823ZYKSZ-R7 uniquely combines automotive temperature range, integrated manual reset with debounce, and a production-proven 1.6 sec watchdog - making it the only option among the three qualified for ASIL-B diagnostic coverage in powertrain systems.

Availability

ADM823ZYKSZ-R7 is available at Aetrix Electronics and suitable for engine control units, ADAS camera modules, and electric power steering controllers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADM823ZYKSZ-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 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 ADM823 family was engineered specifically for automotive microprocessor supervision - delivering precision reset thresholds, watchdog reliability, and AEC-Q100-compliant packaging in minimal SC70/SOT-23 footprints.

FAQ

What is the exact reset threshold voltage of ADM823ZYKSZ-R7 and its tolerance over temperature?

The ADM823ZYKSZ-R7 has a nominal reset threshold of 2.32 V at 25°C, with a guaranteed range of 2.25 V to 2.38 V across the full −40°C to +125°C operating temperature range. Its temperature coefficient is tightly controlled at 40 ppm/°C, and it includes 5 mV of hysteresis to prevent chatter near the trip point - critical for stable operation during thermal cycling in under-hood environments.

Does ADM823ZYKSZ-R7 support manual reset, and how is the MR pin configured?

Yes, ADM823ZYKSZ-R7 includes a dedicated manual reset (MR) input on Pin 3. It is active-low, internally pulled up to VCC with a 52 kΩ resistor, and requires a minimum pulse width of 1 µs to assert reset. The device integrates on-chip debounce that rejects transients shorter than 100 ns, eliminating the need for external RC filtering in most automotive implementations.

What is the watchdog timeout behavior of ADM823ZYKSZ-R7, and how is it cleared?

The ADM823ZYKSZ-R7 watchdog timer has a typical timeout of 1.6 sec (1.12–2.40 sec range), and it is cleared by any logic transition - rising or falling edge - on the WDI pin lasting ≥50 ns. The timer also resets automatically when VCC falls below threshold or MR is asserted. Leaving WDI floating disables the watchdog function entirely, allowing flexible use in systems where only power supervision is required.

Can ADM823ZYKSZ-R7 operate reliably at VCC below 2.0 V, and what happens to the RESET output?

Yes, ADM823ZYKSZ-R7 guarantees valid RESET output down to VCC = 1 V. At VCC = 1 V, the active-low RESET pin remains logic-low with 50 µA sink capability, ensuring deterministic reset assertion even during deep brownout. This behavior is explicitly characterized in the datasheet and enables safe shutdown sequencing in battery-depleted automotive scenarios.

What package type and dimensions does ADM823ZYKSZ-R7 use, and is it RoHS-compliant?

ADM823ZYKSZ-R7 uses the 5-lead SC70 (KS-5) package, measuring 2.0 mm × 1.25 mm × 0.9 mm, compliant with JEDEC MO-203-AA. It is RoHS-compliant (indicated by the "Z" suffix), lead-free, and halogen-free. The small footprint supports high-density layouts in space-constrained automotive modules such as radar sensors and zone controllers.