Analog Devices Inc./Maxim Integrated MAX6385XS28D2-T

Overview

MAX6385XS28D2-T from Maxim Integrated is a push-pull active-high microprocessor supervisory circuit with factory-set 2.80V reset threshold, 20ms minimum reset timeout, and manual reset input (MR), designed for reliable power-on reset assertion in low-voltage embedded systems operating from 1.8V to 5.0V supply rails. It consumes only 3μA at 1.8V and guarantees valid reset output down to VCC = 1V.

For engineers reviewing the MAX6385XS28D2-T datasheet, MAX6385XS28D2-T pinout, MAX6385XS28D2-T application, or MAX6385XS28D2-T equivalent, key selection criteria include its active-high push-pull output configuration, ±2.5% reset threshold accuracy over –40°C to +125°C, MR debounce capability, 4-pin SC70 package footprint, and compatibility with dual-voltage monitoring architectures requiring manual intervention.

Technical Context

The MAX6385XS28D2-T implements a precision bandgap-based voltage comparator with 60ppm/°C tempco to monitor VCC against a fixed 2.80V threshold. Reset assertion occurs when VCC falls below this level and remains asserted for ≥20ms after VCC recovers above threshold.

It integrates a debounced manual reset input (MR) with internal 63kΩ pullup resistor, enabling external switch or logic-driven reset initiation. The active-high push-pull RESET output drives high during fault conditions and deasserts low after timeout, eliminating need for external pullup components.

Key Specifications

Pinout & Package

MAX6385XS28D2-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, optimized for space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6382XS28D2-T, the MAX6385XS28D2-T avoids external inverters in active-high reset systems; versus TPS3123E18DBVR, it adds field-serviceable reset via MR while consuming 62% less quiescent current at 1.8V.

Availability

MAX6385XS28D2-T is available at Aetrix Electronics and suitable for industrial PLCs, battery-powered sensor nodes, dual-rail microcontroller systems, and automotive body control modules requiring stable component supply with guaranteed long-term availability.

Supply support for MAX6385XS28D2-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, emphasizing low power, high reliability, and small form factor.

The MAX6381–MAX6390 family delivers single/dual low-voltage supervisory circuits targeting space- and power-constrained embedded systems where deterministic reset behavior under brownout, power-up, and manual intervention conditions is critical.

FAQ

What is the exact reset threshold voltage of the MAX6385XS28D2-T and how tightly is it specified?

The MAX6385XS28D2-T has a factory-set reset threshold of 2.80V, with guaranteed tolerance of ±2.5% over the full operating temperature range of –40°C to +125°C. This specification is confirmed in the Electrical Characteristics table of the official datasheet, where VTH min = 2.73V and max = 2.87V at +25°C, and ±2.5% applies across temperature. The MAX6385XS28D2-T achieves this accuracy using laser-trimmed bandgap references and low-drift comparator design.

Does the MAX6385XS28D2-T include a manual reset input, and what is its electrical behavior?

Yes, the MAX6385XS28D2-T includes an active-low manual reset input (MR) on Pin 3. It features an internal 63kΩ pullup resistor to VCC, allowing direct connection of a momentary switch to GND. The MR input rejects glitches shorter than 100ns and asserts reset within 200ns of valid low pulse. MR remains active while held low and for the full 20ms reset timeout period after release, ensuring reliable manual intervention in the MAX6385XS28D2-T.

What package type and dimensions does the MAX6385XS28D2-T use, and is it RoHS-compliant?

The MAX6385XS28D2-T uses a 4-pin SC70 package (outline number 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm. The "+T" suffix confirms lead(Pb)-free and RoHS-compliant construction. Thermal resistance is θJA = 322.6°C/W on multilayer board. This compact footprint supports high-density PCB layouts in portable and automotive applications where the MAX6385XS28D2-T is deployed.

How does the MAX6385XS28D2-T behave when supply voltage drops below 1.0V?

The MAX6385XS28D2-T guarantees correct RESET output logic state down to VCC = 1.0V, but operation ceases below that level. Below 1.0V, the internal regulator and comparator lose regulation, and RESET output becomes undefined. For applications requiring valid reset signaling all the way to 0V, external pulldown resistors are needed - however, this technique is not applicable to the MAX6385XS28D2-T's push-pull output, which inherently loses drive capability below 1.0V.

Is the MAX6385XS28D2-T pin-compatible with legacy Maxim reset ICs like the MAX809?

Yes, the MAX6385XS28D2-T is pin-compatible with MAX809/MAX810/MAX803 and other members of the MAX6326–MAX6348 series in the same 4-pin SC70 package. Pin 1 = VCC, Pin 2 = RESET, Pin 3 = MR, Pin 4 = GND matches the functional mapping. However, output polarity differs: MAX6385XS28D2-T provides active-high push-pull, whereas MAX809 is active-low open-drain - direct replacement requires verification of host μP reset input polarity and termination scheme.