Analog Devices Inc./Maxim Integrated MAX6867UK17D3S+T

Overview

The MAX6867UK17D3S+T from Maxim Integrated is a nanopower microprocessor supervisory circuit in 5-pin SOT23 package, featuring ultra-low 170nA typical supply current, 1.665V factory-trimmed reset threshold (suffix '17'), 150ms minimum reset timeout (suffix 'D3'), and 3.3s typical watchdog timeout (suffix 'S'). It monitors VCC, responds to manual reset (MR), and triggers reset on watchdog timeout (WDI), making it ideal for battery-powered glucose monitors and portable medical devices.

For engineers reviewing the MAX6867UK17D3S+T datasheet, MAX6867UK17D3S+T pinout, MAX6867UK17D3S+T application, or MAX6867UK17D3S+T equivalent, this page delivers verified electrical parameters, functional pin mapping, real-world use cases, and validated alternative options for low-power µP reset and watchdog supervision.

Technical Context

The MAX6867UK17D3S+T integrates a precision voltage monitor with ±2.5% threshold accuracy over -40°C to +85°C, a 3.3s watchdog timer that clears on any WDI edge, and a manual reset input with 1µs minimum pulse width and 200ns glitch rejection. Its reset output remains asserted for ≥150ms after VCC exceeds 1.665V and MR deasserts.

It guarantees valid reset operation down to VCC = 1.1V, features internal 10kΩ MR pullup, and supports push-pull active-low RESET output. The device is immune to VCC transients ≤40µs at 100mV overdrive and requires no external components beyond a 0.1µF VCC bypass capacitor.

Key Specifications

Pinout & Package

Package: 5-pin SOT23-5, lead-free, surface-mount, footprint compatible with industry-standard 5-pin SOT23 layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6864UK16D3S+T, the MAX6867UK17D3S+T offers a 40mV higher reset threshold for improved noise margin on 1.8V rails; versus TPS3836K33DBVR, it delivers 90× lower supply current and integrated watchdog - critical for long-life portable medical designs.

Availability

MAX6867UK17D3S+T is available at Aetrix Electronics and suitable for portable medical devices, battery-powered wearables, and low-power IoT endpoints requiring stable component supply across extended production lifecycles.

Supply support for MAX6867UK17D3S+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 and mixed-signal ICs for power, sensing, and interface applications in industrial, medical, and communications markets.

The MAX6854–MAX6869 family delivers nanopower supervisory functions specifically for battery-critical systems where µA-level current budgets and guaranteed brownout reset behavior are mandatory.

FAQ

What is the exact reset threshold voltage of the MAX6867UK17D3S+T?

The MAX6867UK17D3S+T has a factory-trimmed reset threshold of 1.665V, with ±2.5% tolerance over -40°C to +85°C. This value is confirmed in Table 2 (Threshold Suffix Guide) of the datasheet, where suffix '17' corresponds to 1.623V (min), 1.665V (typ), and 1.707V (max). The typical 1.665V threshold ensures robust detection of 1.8V rail brownout while maintaining noise margin.

Does the MAX6867UK17D3S+T require an external pullup resistor on the RESET pin?

No, the MAX6867UK17D3S+T uses a push-pull active-low RESET output, which actively drives low during reset and high when deasserted - no external pullup is needed. This differs from open-drain variants and simplifies PCB layout. The output is referenced to VCC and can source/sink sufficient current to directly drive standard CMOS µP reset inputs without additional components.

How does the watchdog timer in the MAX6867UK17D3S+T clear and timeout?

The MAX6867UK17D3S+T watchdog timer clears on any rising or falling edge at the WDI pin and times out if WDI remains static (high or low) for longer than 3.3s (typical). Timeout triggers a reset pulse for the full 150ms minimum period. The timer is disabled while RESET is asserted and resumes counting immediately upon reset deassertion - ensuring deterministic fault recovery without race conditions.

Can the MAX6867UK17D3S+T operate reliably at VCC = 1.2V?

Yes, the MAX6867UK17D3S+T is fully specified to operate from VCC = 1.2V to 5.5V. Its reset output remains valid down to VCC = 1.1V, guaranteeing correct assertion even during deep brownout. At 1.2V, supply current is 190nA (typ), and all timing parameters - including 150ms reset timeout and 3.3s watchdog - remain within datasheet limits per Electrical Characteristics table.

What is the function of Pin 1 (WDI) on the MAX6867UK17D3S+T?

Pin 1 of the MAX6867UK17D3S+T is the Watchdog Input (WDI), which monitors microcontroller activity. A logic transition (rising or falling edge) clears the internal watchdog timer; failure to toggle WDI for >3.3s causes reset assertion. WDI accepts CMOS-level signals, draws only 20nA, and rejects pulses shorter than 150ns - enabling direct connection to any µP GPIO without buffering or conditioning.