Analog Devices Inc./Maxim Integrated MAX6385XS45D7-T

Overview

The MAX6385XS45D7-T from Maxim Integrated is a factory-trimmed, active-high push-pull μP supervisory circuit with 4.50V reset threshold, 1200ms VCC reset timeout, and 150ms manual reset timeout. It monitors single-supply voltage (1.0V–5.5V), consumes only 3μA at 1.8V, and guarantees valid reset output down to VCC = 1V. Used in battery-powered microcontroller systems requiring reliable power-on reset and operator-initiated recovery.

For engineers reviewing the MAX6385XS45D7-T datasheet, MAX6385XS45D7-T pinout, MAX6385XS45D7-T application, or MAX6385XS45D7-T equivalent, key selection criteria include its 4.50V ±2.5% threshold accuracy over –40°C to +125°C, debounced manual reset input with internal 63kΩ pullup, 4-pin SC70 package, and compatibility with dual-voltage monitoring systems via external resistor-divider configurations.

Technical Context

This device implements a precision bandgap-based voltage comparator for VCC monitoring and a digital timeout counter synchronized to power-state transitions. Its reset assertion logic responds to both VCC falling below 4.50V and MR pin low assertion, with independent timeout periods (1200ms for VCC, 150ms for MR) governed by on-chip RC timing.

The 4-pin SC70 package integrates dedicated VCC, GND, RESET, and MR terminals - no auxiliary RESET IN or NC pins - confirming its role as a single-supply, manual-reset-capable supervisor without secondary voltage monitoring capability. Reset output remains valid across full operating voltage (1.0V–5.5V) and temperature range (–40°C to +125°C).

Key Specifications

Pinout & Package

MAX6385XS45D7-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 portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS45D7-T, MAX6385XS45D4-T offers reduced VCC timeout (1120ms vs. 1200ms) and MR timeout (140ms vs. 150ms), while TPS3808G33DBVR trades manual reset capability and adjustable threshold for lower quiescent current and tighter 3.3V tolerance - making each suitable for distinct system-level timing and control requirements.

Availability

MAX6385XS45D7-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 and AEC-Q100-aligned reliability.

Supply support for MAX6385XS45D7-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, mixed-signal, and power management ICs for demanding industrial, automotive, and computing applications.

The MAX6381–MAX6390 family delivers ultra-low-power, factory-trimmed reset supervisors targeting battery-operated and thermally rugged systems where guaranteed reset validity down to 1V and minimal footprint are critical design constraints.

FAQ

What is the exact reset threshold voltage of the MAX6385XS45D7-T and how accurate is it over temperature?

The MAX6385XS45D7-T has a factory-set nominal reset threshold of 4.50V, with guaranteed accuracy of ±2.5% over the full operating temperature range of –40°C to +125°C. This specification is confirmed in the Electrical Characteristics table under "VCC Reset Threshold" and applies to all units without user trimming or external calibration. The MAX6385XS45D7-T maintains this precision due to integrated bandgap reference and laser-trimmed resistive divider.

Does the MAX6385XS45D7-T support dual-voltage monitoring like some other members of the MAX6381–MAX6390 family?

No, the MAX6385XS45D7-T does not support dual-voltage monitoring. It is configured exclusively for single-supply VCC supervision and includes a manual reset (MR) input. Unlike MAX6387/MAX6388/MAX6389 variants, it lacks the RESET IN pin required for auxiliary voltage monitoring via external resistor divider. Its 4-pin SC70 pinout (VCC, RESET, GND, MR) confirms this single-rail architecture.

What are the absolute maximum ratings for VCC and MR inputs on the MAX6385XS45D7-T?

The MAX6385XS45D7-T specifies an absolute maximum VCC-to-GND rating of –0.3V to +6.0V and an MR input rating of –0.3V to (VCC + 0.3V). These limits are defined in the Absolute Maximum Ratings table and apply regardless of operating mode. Exceeding them risks permanent damage. For reliable operation, VCC should remain within 1.0V–5.5V, and MR must be driven within its specified VIH/VIL thresholds relative to the applied VCC.

Can the MAX6385XS45D7-T's manual reset input be left unconnected, and what happens if it is?

Yes, the MR input of the MAX6385XS45D7-T can be left unconnected because it features an internal 63kΩ pullup resistor to VCC. When floating, MR remains at logic high, disabling manual reset assertion. If externally driven, MR must be pulled below 0.3×VCC (for VTH < 4V) to assert reset. Leaving MR unconnected is safe and common in designs where hardware reset is unnecessary - the MAX6385XS45D7-T will still perform automatic VCC monitoring and reset generation.

Is the MAX6385XS45D7-T pin-compatible with legacy Maxim reset ICs such as the MAX809 or MAX6326?

Yes, the MAX6385XS45D7-T is pin-compatible with MAX809, MAX810, MAX803, MAX6326, MAX6327, MAX6328, MAX6346, MAX6347, MAX6348, and MAX6711/MAX6712/MAX6713 - as explicitly stated in the Features section of the datasheet. This compatibility applies specifically to the 4-pin SC70 variant (MAX6385XSxxDx-T), enabling drop-in replacement in existing layouts without PCB revision, provided the reset threshold and timeout requirements align.