Analog Devices Inc. ADM812MART-REEL7

Overview

ADM812MART-REEL7 from Analog Devices is a microprocessor supervisory circuit in 4-lead SOT-143 (RA-4) package, providing active-high reset output with 4.38 V nominal reset threshold, 140–560 ms power-on reset timeout, 5 µA typical supply current, and operation across −40°C to +85°C for reliable system initialization in embedded controllers and safety-critical instrumentation.

For engineers reviewing the ADM812MART-REEL7 datasheet, ADM812MART-REEL7 pinout, ADM812MART-REEL7 application, or ADM812MART-REEL7 equivalent, this page delivers verified functional identity, precise voltage monitoring specs, manual reset timing behavior, thermal stability data, and real-world substitution guidance for industrial and automotive power-up sequencing design.

Technical Context

The ADM812MART-REEL7 implements a precision bandgap reference-based voltage monitor with ±2.5% threshold accuracy over temperature, guaranteeing reset assertion down to VCC = 1.2 V at −40°C to +85°C. Its internal timer ensures minimum 140 ms active-high RESET pulse after VCC exceeds 4.46 V (max threshold), with typical 240 ms duration.

It features debounced manual reset input (MR) accepting ≥10 µs pulses while rejecting <100 ns glitches, and supports direct interfacing to 3 V/5 V logic via RESET output that sources ≥150 µA at 0.8 × VCC when VCC > 1.8 V. The device maintains valid RESET state during brownout and power-down transitions.

Key Specifications

Pinout & Package

ADM812MART-REEL7 is housed in a JEDEC-compliant 4-lead SOT-143 (RA-4) surface-mount package, 2.90 mm × 1.30 mm × 1.07 mm, with gull-wing leads and 1.92 mm lead-to-lead pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX812MESA+ and TPS3808G33DBVR, ADM812MART-REEL7 uniquely combines 4.38 V precision monitoring, SOT-143 space efficiency, integrated debounced MR, and sub-15 µA operation - making it optimal for cost-sensitive, size-constrained 5 V microcontroller systems needing guaranteed reset timing and industrial temperature support.

Availability

ADM812MART-REEL7 is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, safety-critical medical instruments, portable test equipment, and embedded instrumentation requiring stable component supply with guaranteed RoHS compliance and full lifecycle traceability.

Supply support for ADM812MART-REEL7 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, serving industrial, automotive, communications, and healthcare markets since 1965.

The ADM811/ADM812 family was designed specifically for robust, low-power microprocessor supervision in harsh environments - delivering precision voltage monitoring, glitch immunity, and guaranteed reset timing without software intervention.

FAQ

What is the exact reset threshold voltage of ADM812MART-REEL7 and how does it vary with temperature?

The ADM812MART-REEL7 has a nominal reset threshold of 4.38 V at 25°C, with a guaranteed range of 4.30 V to 4.46 V. Over the full operating temperature range of −40°C to +85°C, the threshold shifts to 4.25 V (min) to 4.50 V (max), corresponding to ±2.5% tolerance. This variation is characterized by a 30 ppm/°C temperature coefficient, ensuring predictable behavior in thermal cycling applications. The ADM812MART-REEL7 datasheet specifies these values in Table 1 under "RESET VOLTAGE THRESHOLD" for the M-suffix variant.

Does ADM812MART-REEL7 support manual reset, and what are the electrical requirements for the MR pin?

Yes, ADM812MART-REEL7 includes a debounced manual reset (MR) input on Pin 3. It is active-low and requires a logic-low pulse ≥10 µs to trigger reset; pulses shorter than 100 ns are rejected. The MR pin recognizes a falling edge below 0.8 V (for L/M variants) or 0.25 × VCC (for R/S/T/Z variants) and a rising edge above 2.3 V (L/M) or 0.7 × VCC (R/S/T/Z). For ADM812MART-REEL7 (M-suffix), MR must fall below 0.8 V and rise above 2.3 V with VCC > VTH(MAX). Leaving MR floating is not recommended - a pull-up resistor is required.

What is the power-on reset timeout duration for ADM812MART-REEL7, and is it adjustable?

The ADM812MART-REEL7 provides a fixed power-on reset timeout of 140 ms minimum and 560 ms maximum, with a typical duration of 240 ms after VCC rises above the reset threshold. This timing is generated by an internal oscillator and is not user-adjustable. The specification is confirmed in Table 1 under "RESET ACTIVE TIMEOUT PERIOD" for ADM811/ADM812 M-suffix devices. No external components are needed to set or modify this delay - it is fully integrated and factory-trimmed.

How does ADM812MART-REEL7 behave during power-down, and what is its minimum operating VCC?

During power-down, ADM812MART-REEL7 maintains a valid active-high RESET output down to VCC = 1.2 V at −40°C to +85°C (1.0 V min at 0°C to 70°C), ensuring the microprocessor remains held in reset until supply collapse is complete. Below 0.8 V, RESET enters high-impedance state - a 100 kΩ pull-down resistor to GND is recommended to prevent floating logic levels. This behavior is documented in the "ENSURING A VALID RESET/RESET OUTPUT DOWN TO VCC = 0 V" section and Figure 11 of the ADM812MART-REEL7 datasheet.

Is ADM812MART-REEL7 RoHS compliant, and what is its packaging format?

Yes, ADM812MART-REEL7 is RoHS compliant, indicated by the "Z" suffix in its full ordering code (ADM812MARTZ-REEL7), and carries the M6D branding per the Analog Devices ordering guide. It is supplied in a 3,000-piece 8 mm tape-and-reel format (REEL7), packaged in JEDEC-standard 4-lead SOT-143 (RA-4) with gull-wing leads. The device meets EU Directive 2011/65/EU and is compatible with standard reflow soldering profiles.