Analog Devices Inc./Maxim Integrated MAX6385XS34D7-T

Overview

MAX6385XS34D7-T from Maxim Integrated is a low-power microprocessor supervisory circuit with active-high push-pull reset output, factory-set 3.40V reset threshold (±2.5% over -40°C to +125°C), 1200ms VCC reset timeout, and debounced manual reset input. It monitors single supply voltage in battery-powered embedded systems, ensuring reliable μP initialization during power-up, brownout, or manual intervention.

For engineers reviewing the MAX6385XS34D7-T datasheet, MAX6385XS34D7-T pinout, MAX6385XS34D7-T application, or MAX6385XS34D7-T equivalent, key selection criteria include its 3μA supply current at 1.8V, guaranteed reset validity down to VCC = 1V, 4-pin SC70 package footprint, and compatibility with dual-voltage monitoring architectures requiring auxiliary reset capability.

Technical Context

The MAX6385XS34D7-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 1200ms minimum reset assertion period after VCC recovery, independent of supply ramp rate.

It features a dedicated MR input with internal 63kΩ pullup resistor, supporting TTL/CMOS-compatible manual reset triggering; reset remains asserted for the full timeout after MR release. The active-high push-pull output drives directly into μP reset inputs without external pullups and remains valid down to VCC = 1V.

Key Specifications

Pinout & Package

MAX6385XS34D7-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 wearable electronics.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS34D7-T, the MAX6385XS34D4-T offers tighter timing control for rapid-reboot systems, while the MAX6326XR34D7-T trades lower power for proven field reliability in mature industrial designs-neither is pin-to-pin drop-in due to differing MR debounce architecture and thermal characteristics.

Availability

MAX6385XS34D7-T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, automotive body control units, and smart home hub power management requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6385XS34D7-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 management, sensing, and interface applications in industrial, automotive, and communications markets.

The MAX6381–MAX6390 family delivers ultra-low-power, high-accuracy reset supervision for battery-operated and thermally demanding embedded systems, emphasizing guaranteed operation from 1V VCC and AEC-Q100 qualification for automotive use cases.

FAQ

What is the exact reset threshold voltage of MAX6385XS34D7-T and how stable is it over temperature?

The MAX6385XS34D7-T has a factory-set nominal reset threshold of 3.40V, with guaranteed accuracy of ±2.5% over the full -40°C to +125°C operating range. Its temperature coefficient is 60ppm/°C, meaning the threshold drifts no more than ±0.026V across the entire temperature span. This stability ensures consistent brownout detection in automotive and industrial environments where supply rails fluctuate with ambient conditions.

Does MAX6385XS34D7-T support manual reset, and what are the electrical requirements for the MR pin?

Yes, MAX6385XS34D7-T includes a debounced manual reset input (MR) with an internal 63kΩ pullup resistor to VCC. To assert reset, drive MR below 0.3×VCC (for VTH < 4V) for ≥1μs; the device rejects glitches ≥100ns. MR can be interfaced directly with open-drain logic or a momentary switch to GND. No external components are required unless additional noise immunity is needed in high-EMI environments.

What is the minimum supply voltage at which MAX6385XS34D7-T guarantees correct reset output behavior?

MAX6385XS34D7-T guarantees valid reset output logic states down to VCC = 1.0V. Below this level, the internal comparator and timer may become indeterminate. This 1V specification ensures reliable μP reset assertion during deep brownout events common in battery-powered systems nearing end-of-life, where other supervisors may fail to assert reset correctly.

How does the 1200ms reset timeout of MAX6385XS34D7-T compare to similar Maxim reset ICs?

The MAX6385XS34D7-T's 1200ms minimum reset timeout is the longest standard option in the MAX6381–MAX6390 family, matching only the D7 suffix variants. It exceeds the 1120ms (D4) and 560ms (D6) timeouts of comparable parts, providing extended hold time for complex processors or peripherals requiring longer initialization sequences-such as FPGA configuration or multi-rail power sequencing coordination.

Is MAX6385XS34D7-T compatible with existing PCB footprints for older Maxim reset ICs like MAX809?

MAX6385XS34D7-T is pin-compatible with MAX809/MAX810/MAX803 and other legacy Maxim reset ICs in the same 4-pin SC70 package. Its pinout (VCC, RESET, GND, MR) matches the functional assignment of those devices, enabling drop-in replacement in most cases-provided the original design used an active-high reset output and did not rely on open-drain behavior or auxiliary monitoring features absent in MAX809.