Analog Devices Inc./Maxim Integrated MAX6385XS31D1+T

Overview

MAX6385XS31D1+T from Maxim Integrated is a push-pull active-high microprocessor supervisory circuit with factory-set 3.08V reset threshold, 140ms minimum VCC reset timeout, and manual reset input. It monitors +1.8V to +5.0V supply rails, consumes only 3μA at +1.8V, guarantees valid reset output down to VCC = 1V, and operates across –40°C to +125°C for use in battery-powered industrial controllers.

For engineers reviewing the MAX6385XS31D1+T datasheet, MAX6385XS31D1+T pinout, MAX6385XS31D1+T application, or MAX6385XS31D1+T equivalent, key selection criteria include its 3.08V ±2.5% threshold accuracy over temperature, 140ms reset timeout, active-high push-pull output drive capability, MR input with internal 63kΩ pullup, and 4-pin SC70 package compatibility with space-constrained embedded systems.

Technical Context

The MAX6385XS31D1+T implements a precision bandgap-based voltage comparator with ±2.5% threshold accuracy over –40°C to +125°C and 60ppm/°C tempco. Its internal timer generates a guaranteed-minimum 140ms reset assertion after VCC rises above 3.08V or after MR release.

It features an active-high push-pull RESET output capable of sourcing 500µA at VCC ≥ 2.5V while maintaining VOH ≥ 0.8×VCC, and includes a debounced manual reset input (MR) with 1µs minimum pulse width support and 100ns glitch rejection - all within a 4-pin SC70 footprint requiring no external components for basic operation.

Key Specifications

Pinout & Package

MAX6385XS31D1+T is housed in a RoHS-compliant 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 1.0mm × 1.0mm × 0.5mm with 0.65mm pitch. The compact footprint supports automated placement in wearables, medical patches, and ultra-small industrial modules.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6385XS31D2+T, the MAX6385XS31D1+T offers shorter reset assertion ideal for fast-boot MCUs; compared with TPS3808G30DBVR, it delivers identical threshold voltage in a smaller 4-pin SC70 package but with looser accuracy spec - making it optimal for cost-sensitive, space-constrained industrial designs where 2.5% tolerance is sufficient.

Availability

MAX6385XS31D1+T is available at Aetrix Electronics and suitable for industrial PLC I/O modules, battery-powered data loggers, and medical wearable patches requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6385XS31D1+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 industrial, automotive, and computing applications, with expertise in low-power supervision and power management.

The MAX6381–MAX6390 family was engineered specifically for space-constrained, battery-sensitive systems needing highly accurate, ultra-low-quiescent-current reset supervision - delivering factory-trimmed thresholds and guaranteed timeout periods in sub-1mm² packages.

FAQ

What is the exact reset threshold voltage of MAX6385XS31D1+T and how tightly is it specified?

The MAX6385XS31D1+T has a factory-set reset threshold of 3.08V, with ±2.5% accuracy guaranteed over the full –40°C to +125°C operating temperature range. This specification is confirmed in the Electrical Characteristics table of the official datasheet, where VTH min = 3.00V and max = 3.15V at +25°C, and ±2.5% tolerance applies across temperature. The "31" suffix in the part number explicitly denotes the 3.08V threshold per the Reset Threshold table.

Does MAX6385XS31D1+T support manual reset functionality, and what are the electrical requirements for the MR pin?

Yes, MAX6385XS31D1+T includes a dedicated MR (manual reset) input with an internal 63kΩ pullup resistor to VCC. To assert reset, MR must be driven low to ≤0.3×VCC (e.g., ≤0.924V at VCC = 3.08V). The pin accepts TTL/CMOS logic levels and supports minimum pulse widths of 1µs. No external components are required - a normally open momentary switch from MR to GND suffices for field reset.

What is the guaranteed minimum reset timeout period for MAX6385XS31D1+T, and how is it triggered?

The MAX6385XS31D1+T provides a guaranteed minimum reset timeout of 140ms (suffix "D3") following either VCC recovery above 3.08V or release of the MR pin. This timeout is generated by an internal oscillator-based timer and is specified under worst-case process/voltage/temperature conditions. The "D3" in the part number directly maps to the 140ms entry in the Reset Timeout Delay table, with typical value 280ms but guaranteed minimum 140ms.

Can MAX6385XS31D1+T operate reliably at supply voltages below 1.8V, and what is its lowest functional VCC?

Yes, MAX6385XS31D1+T operates down to VCC = 1.0V, and its RESET output state is guaranteed valid for VCC ≥ 1V. While typical supply current is specified at 3μA at +1.8V, the device remains fully functional - including accurate threshold comparison and timer operation - at 1.0V. This enables use in deep brownout scenarios where other supervisors may fail, though output drive strength degrades linearly with VCC.

What package type and dimensions does MAX6385XS31D1+T use, and is it RoHS-compliant?

MAX6385XS31D1+T uses a 4-pin SC70 package (outline number 21-0098, land pattern 90-0187), measuring 1.0mm × 1.0mm × 0.5mm with 0.65mm pin pitch. The "+T" suffix confirms lead(Pb)-free and RoHS-compliant construction. This ultra-compact package supports high-density PCB layouts in portable and wearable electronics where board space is severely constrained.