Analog Devices Inc./Maxim Integrated MAX6386LT26D3+T

Overview

MAX6386LT26D3+T from Maxim Integrated is a low-power microprocessor supervisory circuit with open-drain active-low reset output, factory-set 2.63V reset threshold (±2.5% over -40°C to +125°C), 140ms minimum VCC reset timeout, and debounced manual reset input (MR) with internal 63kΩ pullup. It monitors single supply voltage in battery-powered embedded systems requiring reliable power-on reset and brownout protection.

For engineers reviewing the MAX6386LT26D3+T datasheet, MAX6386LT26D3+T pinout, MAX6386LT26D3+T application, or MAX6386LT26D3+T equivalent, key selection criteria include its 2.63V threshold accuracy, 140ms reset timeout, MR input timing behavior, open-drain output compatibility with mixed-voltage systems, and operation down to VCC = 1.0V with guaranteed reset state validity.

Technical Context

The MAX6386LT26D3+T implements a precision bandgap-based reset comparator with ±2.5% threshold accuracy across -40°C to +125°C and 60ppm/°C tempco. Its internal timer generates a fixed 140ms minimum reset assertion period after VCC recovers above 2.63V.

It features a dedicated active-low manual reset input (MR) with 1µs minimum pulse width support, 100ns glitch rejection, and 200ns MR-to-reset delay. The open-drain RESET output requires an external pullup and sinks up to 3.2mA at VCC ≥ 4.5V while maintaining VOL ≤ 0.4V.

Key Specifications

Pinout & Package

MAX6386LT26D3+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. This compact footprint supports high-density PCB layouts in space-constrained portable and IoT applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326XR26D3+T and TPS3808G33DBVR, MAX6386LT26D3+T uniquely combines precise 2.63V supervision, 140ms timeout, open-drain flexibility, and integrated MR - making it optimal for battery-powered and multi-rail designs where reset coordination and user control are essential.

Availability

MAX6386LT26D3+T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, automotive body control units, and smart energy meters requiring stable component supply and long-term lifecycle support.

Supply support for MAX6386LT26D3+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 demanding industrial, automotive, and computing applications, with emphasis on low-power, high-reliability solutions.

The MAX6381–MAX6390 family delivers single/dual low-voltage microprocessor reset circuits optimized for battery-powered and harsh-environment systems where accuracy, ultra-low current, and robust transient immunity are critical.

FAQ

What is the exact reset threshold voltage of MAX6386LT26D3+T and how stable is it over temperature?

The MAX6386LT26D3+T has a factory-set nominal reset threshold of 2.63V, with guaranteed accuracy of ±2.5% over the full operating temperature range of -40°C to +125°C. Its temperature coefficient is 60ppm/°C, meaning threshold drift is limited to approximately ±15mV across the entire range - sufficient for reliable brownout detection in automotive and industrial applications without external calibration.

Does MAX6386LT26D3+T support manual reset, and what are the electrical requirements for the MR pin?

Yes, MAX6386LT26D3+T includes a dedicated MR (manual reset) input with an internal 63kΩ pullup resistor to VCC. To assert reset, drive MR low with a logic signal or momentary switch to GND. The input accepts TTL/CMOS levels, rejects glitches shorter than 100ns, and requires a minimum pulse width of 1µs. No external components are needed unless additional noise immunity is required - in which case a 0.1µF capacitor from MR to GND is recommended.

What is the function of the RESET pin on MAX6386LT26D3+T and what external components does it require?

The RESET pin on MAX6386LT26D3+T is an open-drain active-low output that must be pulled up externally to a compatible voltage rail (e.g., 3.3V or 5.0V) using a resistor typically between 10kΩ and 100kΩ. This configuration allows wired-OR connection with other reset sources and level translation across different logic families. The output sinks up to 3.2mA at VCC ≥ 4.5V while maintaining VOL ≤ 0.4V, ensuring robust drive capability for multiple downstream loads.

How does MAX6386LT26D3+T behave when VCC drops below 1.0V, and is reset assertion guaranteed down to 0V?

MAX6386LT26D3+T guarantees correct RESET output logic state down to VCC = 1.0V. Below 1.0V, the internal circuitry cannot maintain active drive, so the open-drain RESET pin floats high (due to external pullup). For applications requiring valid reset signaling all the way to 0V, a pullup resistor alone is insufficient - the device's open-drain architecture means no active pull-down is available at ultra-low VCC. Therefore, MAX6386LT26D3+T is not specified for 0V operation, unlike push-pull variants.

Is MAX6386LT26D3+T pin-compatible with legacy Maxim reset ICs like MAX809 or MAX6326?

No, MAX6386LT26D3+T is not pin-compatible with MAX809 (3-pin SOT23) or MAX6326 (3-pin SC70), as it uses a 4-pin SC70 package with dedicated MR and RESET pins. However, it is functionally and footprint-compatible with other 4-pin SC70 members of the MAX6384–MAX6390 family (e.g., MAX6384XS26D3+T), sharing identical pinout, thermal characteristics, and land pattern (90-0187), enabling drop-in replacement within that series.