Analog Devices Inc./Maxim Integrated MAX812LEUS+T

Overview

MAX812LEUS+T from Maxim Integrated is a low-power microprocessor supervisory circuit that monitors 5V power supplies and asserts an active-high reset signal when VCC falls below 4.63V, with guaranteed reset validity over -40°C to +85°C and 140ms minimum reset timeout-used in portable controllers and embedded systems requiring reliable brownout protection.

For engineers reviewing the MAX812LEUS+T datasheet, MAX812LEUS+T pinout, MAX812LEUS+T application, or MAX812LEUS+T equivalent, this page delivers verified electrical parameters, SOT143 package mapping, manual reset timing behavior, temperature-stable threshold accuracy, and real-world interfacing guidance for μP reset coordination.

Technical Context

The MAX812LEUS+T implements a precision voltage comparator with factory-trimmed 4.63V reset threshold (±0.04V over temperature), internal 140ms reset timeout timer, and glitch-immune manual reset input (MR) with 20kΩ internal pull-up. It operates from 1.2V to 5.5V supply and guarantees RESET output validity across full industrial temperature range.

Its active-high RESET output drives CMOS/TTL loads up to 150µA source current (0.8×VCC) and sinks 3.2mA while maintaining VOL ≤ 0.4V at VCC = VTH(MIN); MR-to-RESET propagation delay is 0.5µs, and VCC transient immunity rejects 40µs negative glitches down to 125mV below threshold.

Key Specifications

Pinout & Package

MAX812LEUS+T uses a 4-pin SOT143 surface-mount package (outline 21-0052, land pattern 90-0183), measuring 2.9mm × 1.6mm × 1.1mm, with gull-wing leads and RoHS-compliant lead-free finish (+T suffix).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage monitor applications.

Compared with TPS3808G15DBVR and ADM6713LAKSZ-REEL7, the MAX812LEUS+T provides optimal 5V-specific supervision with minimal quiescent current, precise threshold matching, and zero extra features-making it ideal for cost-sensitive, space-constrained industrial controllers where only voltage monitoring and reset are required.

Availability

MAX812LEUS+T is available at Aetrix Electronics and suitable for industrial controllers, portable medical devices, automotive body electronics, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX812LEUS+T 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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for industrial, automotive, and computing applications-with emphasis on reliability, integration, and low-power operation.

The MAX811/MAX812 family was engineered specifically for microprocessor power-supply supervision in space- and power-constrained embedded systems-delivering factory-trimmed thresholds, guaranteed timing, and robust noise immunity in minimal 4-pin SOT143 form factor.

FAQ

What is the exact reset threshold voltage for MAX812LEUS+T?

The MAX812LEUS+T has a nominal reset threshold of 4.63V, with guaranteed limits of 4.50V (min) to 4.75V (max) over the full -40°C to +85°C operating temperature range. This value is factory-trimmed and specified in the Electrical Characteristics table of the official datasheet; it ensures reset assertion before common 5V ±5% supplies fall below the 4.5V minimum required by most microcontrollers.

Does MAX812LEUS+T support manual reset functionality, and how is it implemented?

Yes, MAX812LEUS+T includes a dedicated manual reset input (MR) on Pin 3. It is an active-low input with a built-in 20kΩ pull-up resistor, allowing direct connection to a momentary switch to ground-no external components required. When asserted, MR holds RESET high for at least 140ms after release, and the device rejects noise spikes shorter than 100ns, making it suitable for noisy industrial environments.

What is the supply current consumption of MAX812LEUS+T, and under what conditions is it measured?

The MAX812LEUS+T draws 6µA typical supply current at VCC = 5.5V and TA = +25°C, with a maximum of 15µA over temperature. This ultra-low quiescent current enables direct battery connection in always-on monitoring applications-such as portable medical devices-without compromising operational lifetime, and is confirmed in the Electrical Characteristics table of the Maxim Integrated datasheet.

Can MAX812LEUS+T operate reliably at VCC voltages below 2V, and what happens to the RESET output?

Yes, MAX812LEUS+T operates down to VCC = 1.2V over temperature. Its RESET output remains valid (VOH ≥ 0.8×VCC, VOL ≤ 0.4V) across this range. Unlike the MAX811, the MAX812LEUS+T does not guarantee output state below 1V-but since most microcontrollers cease operation below 1.8V, this poses no functional limitation in standard 5V-system applications.

Is MAX812LEUS+T pin-compatible with other members of the MAX811/MAX812 family, such as MAX812MEUS+T?

Yes, all MAX811/MAX812 variants-including MAX812LEUS+T and MAX812MEUS+T-share identical 4-pin SOT143 pinout, footprint, and terminal functions. The only differences are reset threshold voltage (4.63V vs. 4.38V) and ordering suffix; electrical timing, MR behavior, supply current, and temperature specs are identical, enabling direct substitution in designs where threshold tolerance permits.