Analog Devices Inc./Maxim Integrated MAX6386LT44D3+

Overview

MAX6386LT44D3+ from Maxim Integrated is a low-power microprocessor supervisory circuit with open-drain active-low reset output, factory-set 4.38V reset threshold (±2.5% over −40°C to +125°C), and 140ms minimum VCC reset timeout. It features a debounced manual reset input (MR) with internal 63kΩ pullup, operates down to VCC = 1.0V, and consumes only 3μA at 1.8V - used in battery-powered embedded controllers and portable instrumentation for reliable power-on reset and brownout protection.

For engineers reviewing the MAX6386LT44D3+ datasheet, MAX6386LT44D3+ pinout, MAX6386LT44D3+ application, or MAX6386LT44D3+ equivalent, key selection considerations include its 4-pin SC70 package, open-drain reset output requiring external pullup, MR-driven reset assertion, and compatibility with dual-voltage monitoring systems where auxiliary reset inputs are not required.

Technical Context

The MAX6386LT44D3+ integrates a precision voltage comparator referenced to an internal bandgap, comparing VCC against a fixed 4.38V threshold with ±2.5% accuracy across −40°C to +125°C. Its internal timer initiates a guaranteed-minimum 140ms reset timeout after VCC rises above threshold or after MR release.

It implements a dedicated MR input with 1µs minimum pulse width support, 100ns glitch rejection, and 200ns MR-to-reset delay - all while maintaining valid reset state down to VCC = 1.0V. The open-drain RESET output supports sink currents up to 3.2mA at VCC ≥ 4.5V with VOL ≤ 0.4V.

Key Specifications

Pinout & Package

MAX6386LT44D3+ 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 microprocessor reset applications.

Compared with MAX6386LT44D3+, the /V+ variant adds automotive qualification without altering timing or interface behavior, while TPS3808G33DBVR trades MR capability and adjustable threshold for lower cost in fixed 3.3V applications - neither is pin-compatible, requiring PCB layout changes.

Availability

MAX6386LT44D3+ is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, automotive body control units, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6386LT44D3+ 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, sensing, and connectivity applications in industrial, automotive, and computing markets.

The MAX6381–MAX6390 family delivers ultra-low-power, high-accuracy reset supervision for battery-operated and thermally demanding embedded systems - emphasizing factory-trimmed thresholds, minimal quiescent current, and robust noise immunity.

FAQ

What is the exact reset threshold voltage of MAX6386LT44D3+ and how tightly is it specified?

The MAX6386LT44D3+ has a nominal reset threshold of 4.38V, with a guaranteed range of 4.27V to 4.48V at +25°C and ±2.5% tolerance over −40°C to +125°C. This corresponds to the "44" suffix per Maxim's Reset Threshold table, making MAX6386LT44D3+ suitable for supervising 4.5V rails with margin against dropout. The threshold is factory-trimmed using laser calibration, eliminating external resistor networks.

Does MAX6386LT44D3+ support manual reset, and what are the electrical requirements for the MR pin?

Yes, MAX6386LT44D3+ 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) or below 0.8V (for VTH > 4V); a standard momentary switch to GND suffices. The device rejects glitches as short as 100ns and requires only 1µs minimum low pulse width - no external debounce components are needed.

What package type and footprint does MAX6386LT44D3+ use, and is it RoHS-compliant?

MAX6386LT44D3+ uses a 4-pin SC70 package (outline 21-0098, land pattern 90-0187), measuring 2.0mm × 2.1mm × 0.95mm. The "+" suffix confirms it is lead(Pb)-free and RoHS-compliant. This compact footprint supports high-density PCB layouts in portable equipment, and reflow soldering is rated to +260°C per JEDEC J-STD-020.

Can MAX6386LT44D3+ operate reliably during deep brownout conditions?

Yes, MAX6386LT44D3+ guarantees valid reset output state down to VCC = 1.0V, ensuring deterministic behavior even during severe undervoltage events. Its internal comparators and timer remain functional below typical logic thresholds, and the open-drain RESET output maintains defined logic levels (VOL ≤ 0.4V at ISINK = 3.2mA) as long as VCC ≥ 1.0V - critical for fail-safe shutdown in battery-depleted systems.

How does the 140ms reset timeout (D3 suffix) of MAX6386LT44D3+ compare to other timing options in the family?

The D3 suffix denotes a minimum 140ms reset timeout - longer than D1 (1ms) and D2 (20ms) but shorter than D5 (280ms), D6 (560ms), and D4/D7 (1120ms/1200ms). This value balances μP initialization time against system responsiveness: sufficient for most ARM Cortex-M boot sequences, yet avoids excessive delay in fault-recovery cycles. Actual timeout varies ±100% due to process/temp drift, per datasheet tRP specification.