Analog Devices Inc. ADM823YYKS-R7

Overview

ADM823YYKS-R7 from Analog Devices is a precision supervisory circuit with integrated watchdog timer and manual reset input, designed for microprocessor supply voltage monitoring in automotive-grade systems. It features a 2.19 V reset threshold (±0.06 V over temperature), 140 ms minimum reset timeout, 1.6 s typical watchdog timeout, push-pull active-low RESET output, and operates down to VCC = 1 V with only 5 µA typical supply current. It is used in engine control units and battery management systems requiring reliable brownout detection and code execution integrity.

For engineers reviewing the ADM823YYKS-R7 datasheet, ADM823YYKS-R7 pinout, ADM823YYKS-R7 application, or ADM823YYKS-R7 equivalent, key selection criteria include its SC70-5 package footprint, guaranteed reset validity at low VCC, watchdog pulse timing constraints, and compatibility with 2.19 V rail supervision in harsh-temperature embedded systems.

Technical Context

The ADM823YYKS-R7 implements a precision bandgap-based voltage reference with 40 ppm/°C temperature coefficient and 5 mV hysteresis to ensure stable reset assertion during VCC transients. Its watchdog detector clears on any logic transition (≥50 ns) at WDI and times out after 1.12–2.40 s if unrefreshed.

It integrates an internal 52 kΩ MR pull-up resistor, supports manual reset pulse widths as short as 1 µs, and guarantees valid push-pull RESET output down to VCC = 1 V - enabling robust reset signaling even during deep brownout conditions before full power collapse.

Key Specifications

Pinout & Package

ADM823YYKS-R7 is housed in a 5-lead SC70 (KS-5) package measuring 2.00 mm × 1.25 mm × 0.90 mm, optimized for space-constrained automotive PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADM823YYKS-R7, MAX6326UT23D3+T omits manual reset capability and targets higher-voltage rails, while TPS3808G12QDBVRQ1 offers greater flexibility in threshold and timeout but increases BOM count and layout complexity - ADM823YYKS-R7 delivers optimal balance of fixed 2.19 V supervision, MR support, and minimal footprint for 2.2 V automotive subsystems.

Availability

ADM823YYKS-R7 is available at Aetrix Electronics and suitable for engine control units, battery management systems, and ADAS camera modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ADM823YYKS-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 and industrial microprocessor supervision - delivering precision reset thresholds, watchdog reliability, and extended temperature operation in minimal SC70/SOT-23 footprints.

FAQ

What is the exact reset threshold voltage of the ADM823YYKS-R7 and how does it vary with temperature?

The ADM823YYKS-R7 has a nominal reset threshold of 2.19 V at 25°C, with a guaranteed range of 2.13 V to 2.25 V across the full −40°C to +125°C operating temperature range. Its temperature coefficient is specified at 40 ppm/°C, meaning threshold drift is tightly controlled - for example, at +125°C, deviation from 25°C value is typically < ±4.2 mV. This stability ensures consistent brownout detection in under-hood automotive environments where ambient temperature swings exceed 160°C.

Does the ADM823YYKS-R7 support manual reset functionality, and what are the electrical requirements for the MR pin?

Yes, the ADM823YYKS-R7 includes a dedicated manual reset (MR) input on Pin 3. It is active-low with an internal 52 kΩ pull-up resistor to VCC, eliminating external bias components. A valid reset is asserted when MR is driven below 0.3 × VCC for ≥1 µs. The pin rejects fast glitches ≤100 ns and features on-chip debounce - enabling direct connection to a momentary push-button switch between MR and GND without additional RC filtering.

How does the watchdog timer in the ADM823YYKS-R7 operate, and what is the minimum pulse width it detects?

The ADM823YYKS-R7 watchdog timer clears on any logic transition (low-to-high or high-to-low) at the WDI pin (Pin 4) and times out after 1.12–2.40 s if unrefreshed. It detects pulses as narrow as 50 ns, allowing efficient firmware strobing with minimal CPU overhead. The timer also resets automatically during VCC undervoltage or MR assertion - ensuring coordinated recovery across power and software faults. Leaving WDI floating disables the watchdog function entirely.

Can the ADM823YYKS-R7 generate a valid reset signal when VCC drops below 1.5 V, and what is the lowest VCC at which RESET remains functional?

Yes - the ADM823YYKS-R7 guarantees valid push-pull RESET output down to VCC = 1 V, with output voltage specified at 0.3 V (sink) and 0.8 × VCC (source) under load. This means at VCC = 1.2 V, RESET can still drive a logic-low level ≤0.3 V and logic-high level ≥0.96 V into standard CMOS inputs. This capability ensures deterministic reset assertion well into brownout conditions, unlike many supervisors that cease operation above 1.8 V.

What package type and dimensions does the ADM823YYKS-R7 use, and is it compatible with standard SC70 reflow profiles?

The ADM823YYKS-R7 uses the 5-lead SC70 package (JEDEC MO-203-AA, Analog Devices KS-5), measuring 2.00 mm × 1.25 mm × 0.90 mm with 0.65 mm lead pitch. It is fully compatible with standard lead-free reflow profiles (J-STD-020), including peak temperatures up to 260°C for 30 seconds. The package's coplanarity ≤0.10 mm and thin profile support automated optical inspection and high-yield placement in dense automotive PCB assemblies.