Analog Devices Inc./Maxim Integrated MAX6385XS44D2-T

Overview

MAX6385XS44D2-T from Maxim Integrated is a push-pull active-high microprocessor supervisory circuit with factory-set 4.38V 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, and guarantees valid reset output down to VCC = 1V. Used in portable battery-powered equipment for reliable power-up sequencing and brownout protection.

For engineers reviewing the MAX6385XS44D2-T datasheet, MAX6385XS44D2-T pinout, MAX6385XS44D2-T application, or MAX6385XS44D2-T equivalent, key selection criteria include its active-high push-pull output logic, 4.38V ±2.5% threshold accuracy over –40°C to +125°C, MR debounce capability, and 4-pin SC70 package compatibility with space-constrained embedded systems.

Technical Context

The MAX6385XS44D2-T implements a precision bandgap-based voltage comparator with ±2.5% threshold accuracy across temperature, paired with a monolithic timer generating a fixed 20ms minimum reset timeout after VCC recovery. Its internal 63kΩ MR pullup resistor enables direct connection of a momentary switch to GND without external components.

Reset assertion occurs when VCC falls below 4.38V or MR is pulled low; the active-high RESET output remains high for ≥20ms after VCC exceeds 4.38V or MR is released. The device operates down to VCC = 1V, ensuring deterministic reset behavior during deep brownout conditions.

Key Specifications

Pinout & Package

MAX6385XS44D2-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 high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TRD2-T and TPS3808G33DBVR, MAX6385XS44D2-T uniquely combines 4.38V precision threshold, 20ms fast timeout, active-high push-pull output, and integrated MR - making it optimal for compact, battery-sensitive designs needing deterministic reset timing and field-service capability.

Availability

MAX6385XS44D2-T is available at Aetrix Electronics and suitable for portable medical sensors, automotive body control modules, industrial PLC I/O cards, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6385XS44D2-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, high-accuracy μP supervisory circuits targeting battery-powered and thermally harsh environments where reliable power-on reset and brownout protection are mission-critical.

FAQ

What is the exact reset threshold voltage of MAX6385XS44D2-T and how stable is it over temperature?

The MAX6385XS44D2-T has a factory-set nominal reset threshold of 4.38V, with guaranteed accuracy of ±2.5% over the full operating temperature range of –40°C to +125°C. This stability is achieved through laser-trimmed on-chip resistors and a precision bandgap reference, ensuring consistent brownout detection without external calibration. The MAX6385XS44D2-T maintains this specification across all production lots and environmental conditions.

Does MAX6385XS44D2-T require an external pullup resistor on the RESET pin?

No, MAX6385XS44D2-T does not require an external pullup resistor on the RESET pin because it features a push-pull active-high output architecture. The internal driver actively sources current when RESET is asserted (high) and sinks current when deasserted (low), eliminating reliance on external biasing. This simplifies design and improves noise immunity compared to open-drain alternatives. The MAX6385XS44D2-T output meets VOH ≥ 0.8×VCC and VOL ≤ 0.3V specifications across its full voltage and load range.

What is the function and electrical behavior of the MR pin on MAX6385XS44D2-T?

The MR (Manual Reset) pin on MAX6385XS44D2-T is an active-low input with an internal 63kΩ pullup resistor to VCC. Driving MR low for ≥1μs forces the RESET output high for the full 20ms timeout period, regardless of VCC level. When left unconnected, MR remains high due to the internal pullup, allowing normal VCC-monitoring operation. The MAX6385XS44D2-T MR input accepts TTL/CMOS logic levels and tolerates voltages up to VCC + 0.3V, supporting direct interface with microcontrollers or momentary switches.

Can MAX6385XS44D2-T operate reliably when VCC drops below 1.8V?

Yes, MAX6385XS44D2-T is fully specified to operate down to VCC = 1.0V, with guaranteed RESET output logic state validity throughout that range. At VCC = 1.0V, the device continues to assert RESET correctly when VCC falls below 4.38V and maintains the 20ms timeout after recovery. Its 3μA supply current at +1.8V and functional operation to 1.0V make MAX6385XS44D2-T suitable for deep-brownout scenarios in battery-backed systems where supply voltage may sag significantly before shutdown.

What package type and dimensions does MAX6385XS44D2-T use, and is it RoHS-compliant?

MAX6385XS44D2-T uses a 4-pin SC70 package (outline 21-0098) measuring 2.0mm × 2.1mm × 0.95mm, with lead (Pb)-free/RoHS-compliant terminations indicated by the "+T" suffix. The package features gull-wing leads compatible with standard reflow soldering profiles, including peak temperatures up to +260°C. Land pattern 90-0187 is recommended for optimal thermal and mechanical reliability. This compact footprint supports high-density layouts in space-constrained applications such as wearables and automotive ECUs.