Analog Devices Inc./Maxim Integrated MAX6726KALTD3+T

Overview

MAX6726KALTD3+T from Maxim Integrated is a triple-voltage microprocessor supervisory IC monitoring VCC1 (primary), VCC2 (secondary), and RSTIN (auxiliary) supply rails. It asserts an active-low push-pull reset output when any monitored voltage falls below its factory-trimmed threshold (VTH1 = 2.925 V, VTH2 = 1.388 V, VRSTIN = 626.5 mV), maintains reset for 210 ms (min), and operates from -40°C to +85°C in an 8-pin SOT23 package. It is used in multivoltage embedded systems requiring reliable power-on reset and brownout detection.

For engineers reviewing the MAX6726KALTD3+T datasheet, MAX6726KALTD3+T pinout, MAX6726KALTD3+T application, or MAX6726KALTD3+T equivalent, key selection criteria include its triple-supply monitoring capability, guaranteed reset validity down to VCC1/VCC2 = 0.8 V, push-pull RST and RST2 outputs, manual reset input with internal 50 kΩ pullup, and 210 ms minimum reset timeout period.

Technical Context

The MAX6726KALTD3+T implements dual independent voltage comparators for VCC1 and VCC2, plus a dedicated high-impedance RSTIN comparator referenced to a 626.5 mV internal bandgap. Its reset logic combines OR-ed fault conditions (VCC1/VCC2 undervoltage, RSTIN undervoltage, MR assertion) with a monostable timeout circuit ensuring minimum 210 ms reset pulse width after recovery.

It features a push-pull RST output referenced to VCC1 and a separate push-pull RST2 output referenced to VCC2 - enabling independent reset signaling for core and I/O domains. The device includes a manual reset input (MR) with 200 ns delay and 1 µs minimum pulse width requirement, and guarantees correct reset state down to VCC1 or VCC2 = 0.8 V.

Key Specifications

Pinout & Package

MAX6726KALTD3+T is housed in an 8-pin SOT23-8 package (2.0 mm × 2.1 mm × 1.25 mm profile), optimized for space-constrained PCB layouts while supporting thermal dissipation up to 714 mW at +70°C ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple-voltage supervisory applications.

Compared with MAX6725KAUTD3+T and TPS3808G33DBVR, the MAX6726KALTD3+T uniquely delivers push-pull RST/RST2 outputs and factory-trimmed 2.925 V/1.388 V thresholds in an 8-pin SOT23, making it optimal for space-constrained industrial systems requiring zero-external-component reset assertion and guaranteed 210 ms hold time.

Availability

MAX6726KALTD3+T is available at Aetrix Electronics and suitable for industrial PLC controllers, network router power management, battery-powered medical monitors, automated test equipment, and telecom base station control modules requiring stable component supply across extended temperature ranges.

Supply support for MAX6726KALTD3+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) is a semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The MAX6715–MAX6729 family was designed specifically for multivoltage embedded systems needing compact, low-power, triple-rail supervision with guaranteed reset validity down to 0.8 V - addressing reliability gaps in legacy dual-supply supervisors.

FAQ

What is the exact reset threshold voltage for VCC1 on the MAX6726KALTD3+T?

The MAX6726KALTD3+T has a factory-trimmed VCC1 reset threshold of 2.925 V (typical), with a guaranteed range of 2.850 V to 3.000 V over temperature. This value is encoded in the "AL" suffix per Maxim's Reset Voltage Threshold Suffix Guide and applies to the primary supply rail monitoring function of the MAX6726KALTD3+T.

Does the MAX6726KALTD3+T support monitoring a third voltage rail, and how is it configured?

Yes, the MAX6726KALTD3+T supports third-rail monitoring via the RSTIN pin, which has a fixed 626.5 mV internal reference. To monitor a third voltage (e.g., 5 V or 1.8 V), connect an external resistor divider between that rail and GND, with the midpoint fed to RSTIN. The MAX6726KALTD3+T asserts reset when the divided voltage falls below 626.5 mV.

What is the function of Pin 4 (RST2) on the MAX6726KALTD3+T, and how does it differ from Pin 1 (RST)?

Pin 4 (RST2) is an active-low push-pull reset output referenced to VCC2, while Pin 1 (RST) is referenced to VCC1. Both assert under identical fault conditions (VCC1/VCC2/RSTIN undervoltage, MR low), but RST2's voltage swing is bounded by VCC2, enabling independent reset signaling for secondary power domains - a key feature of the MAX6726KALTD3+T not found in dual-supply variants.

What is the minimum reset timeout period specified for the MAX6726KALTD3+T, and how is it set?

The MAX6726KALTD3+T has a minimum reset timeout period of 210 ms, set by the "D3" suffix in its part number per Maxim's Reset Timeout Period Suffix Guide. This timeout is guaranteed over the full -40°C to +85°C operating range and defines the minimum duration RST and RST2 remain asserted after all monitored supplies recover above their thresholds.

Is the manual reset input (MR) on the MAX6726KALTD3+T internally pulled up, and what is its electrical specification?

Yes, the MR pin on the MAX6726KALTD3+T includes an internal 50 kΩ pullup resistor to VCC1, allowing it to be left unconnected when unused. It accepts TTL/CMOS-compatible logic levels: VIH ≥ 0.7 × VCC1 and VIL ≤ 0.3 × VCC1, with a minimum pulse width of 1 µs required to trigger a valid reset - a confirmed specification for the MAX6726KALTD3+T.