Analog Devices Inc./Maxim Integrated MAX6828TUT

Overview

MAX6828TUT from Maxim Integrated is an ultra-low-voltage dual microprocessor supervisory circuit in SOT23-6 package, monitoring primary supply (VCC) and user-adjustable secondary input (RESET IN) with open-drain active-low RESET output. It asserts reset if VCC falls below factory-set threshold (e.g., 2.93V for 'S' suffix), RESET IN drops below 0.63V, MR is pulled low, or watchdog times out after 1.6s. Designed for battery-powered embedded systems requiring reliable power-up/brownout protection.

For engineers reviewing the MAX6828TUT datasheet, MAX6828TUT pinout, MAX6828TUT application, or MAX6828TUT equivalent, this page delivers verified electrical parameters, exact pin functions, real-world timing behavior (140ms min reset timeout, 1.6s watchdog), and validated alternative options - all confirmed against Maxim's official documentation and ordering data.

Technical Context

The MAX6828TUT implements a dual-threshold supervision architecture: one factory-trimmed VCC monitor (2.93V ±3% for 'S' suffix) and one high-impedance RESET IN comparator (0.63V typ threshold) enabling user-defined secondary voltage monitoring down to +0.6V via resistor divider. Its open-drain RESET output supports bidirectional µP reset I/O interfaces like Motorola 68HC11.

It integrates a 1.6s watchdog timer cleared by WDI edges or reset assertion, manual reset with internal 50kΩ pullup, and guaranteed reset validity down to VCC = +1.0V. Immunity to short negative VCC transients (<20µs at 100mV overdrive) ensures robust operation in noisy power environments.

Key Specifications

Pinout & Package

MAX6828TUT is housed in a 6-pin SOT23-6 package (JEDEC MO-178AA), footprint-compatible with industry-standard 3mm × 1.7mm SOT-23 layouts and reflow-solderable per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6828TUT, MAX6827TUT provides identical supervision accuracy and timing but differs in reset polarity and drive type-making it unsuitable for bidirectional µP interfaces-while TPS3808G18DBVR omits critical features including RESET IN adjustability, watchdog, and manual reset, limiting it to basic single-rail use cases.

Availability

MAX6828TUT is available at Aetrix Electronics and suitable for portable/battery-powered equipment, embedded controllers, and intelligent instruments requiring stable component supply across extended temperature ranges (-40°C to +125°C).

Supply support for MAX6828TUT 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 demanding industrial, automotive, and medical applications.

The MAX6826–MAX6831 family was engineered specifically for multivoltage embedded systems needing dual-rail supervision, manual reset, and watchdog functionality in minimal 6-pin SOT23 footprint.

FAQ

What is the factory-set VCC reset threshold voltage for MAX6828TUT?

The MAX6828TUT features a factory-trimmed VCC reset threshold of 2.93V (±3%) for the 'S' suffix variant, optimized for reliable supervision of standard 3.3V power rails across -40°C to +125°C. This value is specified in the Electrical Characteristics table under VTH for MAX68__S devices and is guaranteed over full temperature range without external calibration.

Does MAX6828TUT support monitoring a secondary voltage lower than 0.9V?

Yes, MAX6828TUT supports monitoring secondary voltages as low as +0.6V using its RESET IN pin, which has a fixed 0.63V (typ) internal threshold. By connecting an external resistor divider between the target voltage and GND-with the divider midpoint fed to RESET IN-the device can accurately supervise voltages well below the 0.9V minimum of factory-trimmed VCC2 monitors.

Can MAX6828TUT's watchdog timer be disabled, and how?

Yes, the watchdog timer in MAX6828TUT is disabled by leaving the WDI pin unconnected or driving it with a three-stated buffer. When floating, internal circuitry pulses WDI every ~1.4s to prevent timeout; no external components or configuration registers are required to disable this function. This behavior is documented in the Watchdog Input section of the datasheet.

What is the minimum VCC voltage at which MAX6828TUT guarantees valid reset assertion?

MAX6828TUT guarantees correct reset assertion and release down to VCC = +1.0V, as explicitly stated in the General Description and Absolute Maximum Ratings sections. This ensures deterministic behavior during deep brownout conditions where many competing supervisors cease functioning, making it suitable for ultra-low-voltage battery backup scenarios.

Is MAX6828TUT pin-compatible with other devices in the MAX6826–MAX6831 family?

Yes, all MAX6826–MAX6831 variants-including MAX6828TUT-are pin-compatible in the 6-pin SOT23-6 package, sharing identical pinout (VCC, RESET IN, WDI, MR, GND, RESET). However, functional differences exist: MAX6828TUT uses open-drain RESET, while MAX6826/MAX6827 use push-pull outputs with opposite polarity, requiring schematic review before substitution.