Analog Devices Inc./Maxim Integrated MAX6826RUT

Overview

MAX6826RUT from Maxim Integrated is a dual ultra-low-voltage microprocessor supervisory circuit in SOT23-6 package, monitoring primary supply (VCC) and user-adjustable secondary input (RESET IN) with push-pull active-low RESET output. It asserts reset if VCC falls below 2.93V or RESET IN drops below 0.63V, maintains reset for ≥140ms after recovery, and supports manual reset and 1.6s watchdog timeout - used in portable battery-powered systems requiring reliable brownout protection.

For engineers reviewing the MAX6826RUT datasheet, MAX6826RUT pinout, MAX6826RUT application, or MAX6826RUT equivalent, key selection considerations include its 2.93V VCC threshold, 0.63V adjustable RESET IN monitor, push-pull active-low RESET, guaranteed operation down to VCC = +1.0V, and immunity to short negative VCC transients.

Technical Context

The MAX6826RUT integrates two independent voltage monitors: one factory-trimmed for VCC (2.93V nominal), another high-impedance comparator for external resistor-divider–based RESET IN (0.63V threshold). Its internal 140ms minimum reset timeout delay generator ensures stable deassertion timing after supply recovery.

It features a dedicated manual reset input (MR) with internal 50kΩ pullup and 200ns MR-to-reset propagation delay, plus a watchdog input (WDI) that triggers reset if un-toggled beyond 1.6s - all operating across –40°C to +125°C with supply current as low as 7µA at +3.6V.

Key Specifications

Pinout & Package

MAX6826RUT is housed in a 6-pin SOT23-6 package (2.9mm × 1.6mm × 1.1mm), surface-mount, lead-free compatible, with thermal pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6826RUT, MAX6827RUT offers identical monitoring accuracy and timing but inverted RESET polarity, while TLV809K33DBZR sacrifices dual-monitoring, watchdog, and manual reset to achieve lower cost and smaller footprint - making MAX6826RUT the sole choice for full-featured dual-supply supervision in space-constrained portable systems.

Availability

MAX6826RUT is available at Aetrix Electronics and suitable for portable/battery-powered equipment, embedded controllers, and intelligent instruments requiring stable component supply across automotive-grade temperature range (–40°C to +125°C) and long-term production continuity.

Supply support for MAX6826RUT 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 and mixed-signal ICs for power, sensing, and interface applications, with emphasis on high-reliability industrial and automotive markets.

The MAX6826–MAX6831 family was engineered specifically for multivoltage microprocessor systems needing simultaneous primary/secondary supply monitoring, manual reset, and watchdog supervision in minimal SOT23-6 footprint.

FAQ

What is the exact VCC reset threshold voltage for MAX6826RUT?

The MAX6826RUT has a factory-trimmed VCC reset threshold of 2.93V, specified with ±3% tolerance over the full temperature range (–40°C to +125°C). This value is confirmed in the Electrical Characteristics table under "MAX68__S" suffix, matching the "RUT" ordering code. The threshold remains stable due to on-chip trimming and 60ppm/°C temperature coefficient.

Does MAX6826RUT support monitoring a secondary voltage below 1.0V?

Yes - the MAX6826RUT includes a dedicated RESET IN pin with a fixed 0.63V (typical) internal threshold, enabling monitoring of secondary voltages as low as 0.63V using an external resistor divider. For example, a 1.2V rail can be scaled to 0.63V via R1/R2 network per Figure 5 in the datasheet, preserving accuracy without additional ICs.

What type of RESET output does MAX6826RUT provide, and how is it interfaced?

MAX6826RUT provides a push-pull active-low RESET output. It actively drives low during reset and high-impedance (not driven) when inactive - no external pullup is needed. This simplifies interface with standard µP reset inputs expecting active-low assertion, unlike open-drain variants (e.g., MAX6828RUT) which require external pullup resistors.

Can the watchdog function of MAX6826RUT be disabled, and how?

Yes - the watchdog function of MAX6826RUT is disabled by leaving the WDI pin unconnected or connecting it to a three-stated buffer output. Internally, an open WDI is serviced every ~1.4s by a low-high-low pulse, preventing timeout. No configuration register or external component is required to disable this feature.

Is MAX6826RUT guaranteed to operate correctly at VCC = +1.0V?

Yes - MAX6826RUT is explicitly guaranteed to assert a valid RESET output down to VCC = +1.0V, as stated in the General Description and Absolute Maximum Ratings. This ensures fail-safe reset behavior during deep brownout conditions where other supervisors may lose functionality or produce indeterminate outputs.