Analog Devices Inc./Maxim Integrated MAX6389LT17D3+T

Overview

MAX6389LT17D3+T from Maxim Integrated is a low-power microprocessor supervisory circuit with open-drain active-low reset output, 1.67V factory-set VCC reset threshold (±2.5% over -40°C to +125°C), 140ms minimum reset timeout, and auxiliary RESET IN input for dual-voltage monitoring. It operates from 1.0V to 5.5V supply and consumes only 3μA at 1.8V, targeting battery-powered embedded systems requiring reliable power-on reset and brownout protection.

For engineers reviewing the MAX6389LT17D3+T datasheet, MAX6389LT17D3+T pinout, MAX6389LT17D3+T application, or MAX6389LT17D3+T equivalent, this page delivers verified electrical specifications, SC70-4 package terminal mapping, dual-supply monitoring capability, reset timing accuracy, and validated alternative parts for industrial and automotive-grade designs.

Technical Context

The MAX6389LT17D3+T integrates a precision bandgap reference and comparator to monitor VCC against a fixed 1.67V threshold while simultaneously accepting an external voltage via RESET IN, compared to an internal 1.27V reference. Its open-drain RESET output requires an external pullup and remains valid down to VCC = 1.0V.

It features a dedicated auxiliary reset comparator with ±50nA input leakage and 4.5µs propagation delay from RESET IN fall to RESET assertion, enabling accurate secondary supply monitoring in dual-rail systems such as I/O/core voltage domains. The device uses BiCMOS process technology and is AEC-Q100 qualified in /V variants.

Key Specifications

Pinout & Package

MAX6389LT17D3+T is housed in a RoHS-compliant 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm, suitable for space-constrained portable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6389LT17D3+T, MAX6389XS17D3+T offers identical functionality in a functionally equivalent package, while TLV803EB26DBZR reduces cost and size at the expense of losing the critical RESET IN capability required for dual-rail validation.

Availability

MAX6389LT17D3+T is available at Aetrix Electronics and suitable for industrial PLCs, automotive body controllers, portable medical sensors, battery-powered smart meters, and dual-voltage embedded systems requiring stable component supply with long-term lifecycle assurance.

Supply support for MAX6389LT17D3+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 industrial, automotive, communications, and computing applications, emphasizing low power, high reliability, and AEC-Q100 qualification.

The MAX6381–MAX6390 family delivers ultra-low-power, factory-trimmed μP supervisors with flexible reset configurations and dual-supply monitoring - engineered specifically for safety-critical and battery-sensitive embedded systems.

FAQ

What is the exact reset threshold voltage of MAX6389LT17D3+T and how does it vary with temperature?

The MAX6389LT17D3+T has a nominal VCC reset threshold of 1.67V, with guaranteed tolerance of ±2.5% over the full operating temperature range of -40°C to +125°C. This means the actual threshold stays between 1.62V and 1.71V across temperature extremes. The tempco is specified at 60ppm/°C, contributing minimally to drift within the ±2.5% band. This stability eliminates need for external trimming in automotive and industrial applications.

Does MAX6389LT17D3+T support monitoring a second voltage, and how is it implemented?

Yes, MAX6389LT17D3+T supports dual-voltage monitoring via its dedicated RESET IN pin, which compares an external voltage to an internal 1.27V reference. To set a custom threshold (e.g., 2.5V), connect a resistor divider between the monitored rail and GND, with the midpoint fed to RESET IN. Using R2 = 100kΩ and R1 = 97.2kΩ yields ~2.5V threshold. Input leakage is ≤±50nA, ensuring minimal error from high-impedance dividers.

What is the function of the RESET output on MAX6389LT17D3+T, and what external components are required?

The RESET output of MAX6389LT17D3+T is an open-drain active-low signal requiring an external pullup resistor to the target logic rail (e.g., 3.3V or 5V). It sinks ≥1.2mA while asserted (VOL ≤ 0.3V at VCC ≥ 2.5V) and exhibits ≤1.0μA leakage when deasserted. No series resistor is needed; typical pullup values range from 4.7kΩ to 10kΩ depending on bus capacitance and rise-time requirements.

Can MAX6389LT17D3+T operate reliably at very low supply voltages, and down to what VCC level is RESET guaranteed?

Yes, MAX6389LT17D3+T is guaranteed to maintain correct RESET logic state down to VCC = 1.0V - meaning it asserts reset properly during deep brownout and holds valid levels until VCC recovers above 1.67V. Below 1.0V, operation is not specified. This feature ensures deterministic MCU reset behavior in ultra-low-power wake-up circuits and energy-harvesting systems where supply may dip near 1V.

Is MAX6389LT17D3+T qualified for automotive applications, and what package options support AEC-Q100?

The MAX6389LT17D3+T itself is not automotive-qualified; however, the identical-function MAX6389XS17D3/V+T variant carries AEC-Q100 qualification and uses the same 4-pin SC70 package. Both share identical electrical specs and pinout. For automotive designs requiring qualification, specify the /V suffix version - it undergoes extended temperature testing (-40°C to +125°C) and stress screening per AEC-Q100 Rev H.