Analog Devices Inc./Maxim Integrated MAX6385XS39D2-T

Overview

MAX6385XS39D2-T from Maxim Integrated is a push-pull active-high microprocessor supervisory circuit with factory-set 3.90V reset threshold, 20ms minimum reset timeout, and manual reset input (MR). It monitors VCC from +1.8V to +5.0V, consumes only 3μA at +1.8V, guarantees valid reset output down to VCC = 1V, and operates across –40°C to +125°C. It is used in portable battery-powered equipment requiring reliable power-on reset and brownout protection.

For engineers reviewing the MAX6385XS39D2-T datasheet, MAX6385XS39D2-T pinout, MAX6385XS39D2-T application, or MAX6385XS39D2-T equivalent, key selection criteria include its 3.90V ±2.5% threshold accuracy over temperature, 20ms VCC reset timeout, MR debounce capability, 4-pin SC70 package footprint, and compatibility with dual-voltage systems where core and I/O rails require coordinated reset sequencing.

Technical Context

The MAX6385XS39D2-T implements a precision bandgap-based voltage comparator for VCC monitoring, paired with a digital timeout counter that asserts the active-high RESET output for ≥20ms after VCC rises above 3.90V. Its internal 63kΩ MR pullup resistor enables direct connection of a momentary switch to GND without external components.

This device belongs to the MAX6384–MAX6390 family with 4-pin SC70 packaging, distinguishing it from 3-pin variants by inclusion of MR and dedicated RESET output-enabling manual reset initiation while maintaining compact board area. It does not support auxiliary RESET IN or dual-voltage monitoring.

Key Specifications

Pinout & Package

MAX6385XS39D2-T is housed in a RoHS-compliant 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 1.6mm × 1.6mm × 0.9mm with gull-wing leads. Thermal resistance θ_JA = 322.6°C/W on multilayer board.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS39D2-T, the MAX6385XS39D3-T extends reset hold time for complex boot sequences, while TLV803EB39DBZR trades higher timing margin and ultra-low power for active-low polarity and added external component requirement - neither offers pin compatibility or identical timing behavior.

Availability

MAX6385XS39D2-T is available at Aetrix Electronics and suitable for portable/battery-powered equipment, industrial PLC I/O modules, and automotive body control modules requiring stable component supply and long-lifecycle support.

Supply support for MAX6385XS39D2-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 industrial, automotive, communications, and computing markets.

The MAX6381–MAX6390 family delivers low-power, high-accuracy μP reset supervision for space- and power-constrained applications where reliability across extreme temperatures is critical.

FAQ

What is the exact reset threshold voltage of MAX6385XS39D2-T and how tightly is it specified?

The MAX6385XS39D2-T has a factory-set nominal reset threshold of 3.90V, with guaranteed accuracy of ±2.5% over the full operating temperature range of –40°C to +125°C. This means the actual threshold falls between 3.80V and 4.00V at +25°C, and between 3.79V and 4.00V across temperature extremes - sufficient for robust supervision of standard 3.3V power rails with margin against ripple and noise.

Does MAX6385XS39D2-T support manual reset, and what are the electrical requirements for the MR pin?

Yes, MAX6385XS39D2-T includes an active-low manual reset input (MR) with an internal 63kΩ pullup resistor to VCC. To assert reset, drive MR below 0.3×VCC (e.g., <1.0V at 3.3V VCC); the device guarantees recognition of pulses as short as 1μs. MR remains effective down to VCC = 1.0V, and internal glitch rejection filters out noise spikes shorter than 100ns.

What is the function and timing behavior of the RESET output on MAX6385XS39D2-T?

The RESET output of MAX6385XS39D2-T is an active-high push-pull driver. It goes high when VCC rises above 3.90V and remains high for a minimum of 20ms, ensuring the microprocessor completes power-up initialization. RESET is guaranteed valid down to VCC = 1.0V, and the output can sink 1.2mA at 2.5V - eliminating need for external pullup resistors in most 3.3V system designs.

Which package does MAX6385XS39D2-T use, and are there thermal limitations I should consider?

MAX6385XS39D2-T uses the 4-pin SC70 package (outline 21-0098), measuring 1.6mm × 1.6mm × 0.9mm. On a multilayer PCB, its junction-to-ambient thermal resistance (θ_JA) is 322.6°C/W. At maximum rated power dissipation of 245mW, this implies a ~80°C junction rise above ambient at full load - well within safe limits given its 3μA supply current and typical operation below 100μW.

Is MAX6385XS39D2-T qualified for automotive applications, and what is its temperature rating?

MAX6385XS39D2-T is rated for operation from –40°C to +125°C and is AEC-Q100 qualified when ordered with the /V suffix (e.g., MAX6385XS39D2/V+T). The standard MAX6385XS39D2-T is not automotive-qualified; for automotive use, specify the /V version to ensure stress-tested reliability, extended temperature validation, and PPAP documentation support.