Analog Devices Inc./Maxim Integrated MAX6386XS29D1-T

Overview

MAX6386XS29D1-T from Maxim Integrated is a low-power microprocessor supervisory circuit with open-drain active-low reset output, factory-set 2.93V reset threshold (±2.5% over -40°C to +125°C), 1ms minimum reset timeout, and debounced manual reset input (MR) featuring internal 63kΩ pullup. It monitors VCC from +1.8V to +5.0V and guarantees valid reset state down to VCC = 1V, used in battery-powered controllers and portable instrumentation.

For engineers reviewing the MAX6386XS29D1-T datasheet, MAX6386XS29D1-T pinout, MAX6386XS29D1-T application, or MAX6386XS29D1-T equivalent, key selection criteria include its 2.93V threshold accuracy, 1ms reset delay, MR debounce capability, open-drain output requiring external pullup, and 4-pin SC70 package compatibility with space-constrained embedded systems.

Technical Context

The MAX6386XS29D1-T implements a precision bandgap-based voltage comparator for VCC monitoring and an independent manual reset path with glitch rejection (100ns) and 1µs minimum pulse width support. Its reset assertion logic combines VCC falling below 2.93V and MR low, with reset deassertion delayed by a fixed 1ms timeout after either condition clears.

It uses BiCMOS process technology to achieve ultra-low quiescent current (3µA at +1.8V), operates across -40°C to +125°C, and features negative-going VCC transient immunity up to 35µs for 100mV overdrive - critical for noisy power rails in portable equipment.

Key Specifications

Pinout & Package

MAX6386XS29D1-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, suitable 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 MAX6386XS29D1-T, MAX6326XR29D1+T offers simpler interface but no manual reset, while TLV809K29DBZR trades MR and short timeout for smaller size and wider voltage range - making MAX6386XS29D1-T optimal for compact, feature-complete reset supervision in battery-critical systems.

Availability

MAX6386XS29D1-T is available at Aetrix Electronics and suitable for portable medical sensors, battery-powered data loggers, industrial handheld controllers, and automotive body control modules requiring stable component supply and long-term lifecycle support.

Supply support for MAX6386XS29D1-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 power, sensing, and connectivity applications with emphasis on reliability and low-power operation.

The MAX6381–MAX6390 family delivers single-supply microprocessor supervisory circuits optimized for low-voltage, low-power embedded systems - specifically targeting portable, automotive, and industrial applications demanding guaranteed reset behavior across extreme temperatures.

FAQ

What is the exact reset threshold voltage of the MAX6386XS29D1-T and how stable is it over temperature?

The MAX6386XS29D1-T has a factory-set nominal reset threshold of 2.93V, 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 bandgap references and BiCMOS process design, ensuring consistent brownout detection without external calibration. The MAX6386XS29D1-T maintains this specification across all production units.

Does the MAX6386XS29D1-T require an external pullup resistor on the RESET pin, and why?

Yes, the MAX6386XS29D1-T requires an external pullup resistor on the RESET pin because it features an open-drain active-low output. Without a pullup, the RESET line remains floating when deasserted, risking undefined logic states. A typical value is 10kΩ to the host system's logic voltage (e.g., 3.3V or 5V). This configuration enables wired-OR reset buses and level-shifting - a key design feature of the MAX6386XS29D1-T.

Can the MAX6386XS29D1-T operate reliably when VCC drops below 1.8V, and what is the minimum functional voltage?

Yes, the MAX6386XS29D1-T guarantees correct reset output behavior down to VCC = 1.0V, as specified in its absolute maximum ratings and electrical characteristics. While typical operation starts at +1.8V, the device continues asserting or deasserting RESET with valid logic levels even at 1.0V - critical for detecting deep brownout conditions before complete power loss. This capability is intrinsic to the MAX6386XS29D1-T's architecture.

What is the function and electrical behavior of the MR pin on the MAX6386XS29D1-T?

The MR (Manual Reset) pin on the MAX6386XS29D1-T is an active-low input with an internal 63kΩ pullup resistor to VCC. Driving MR low forces a reset regardless of VCC level, and reset remains asserted for the full 1ms timeout after MR is released. The pin accepts TTL/CMOS logic levels and rejects glitches <100ns. This integrated pullup eliminates external components, distinguishing the MAX6386XS29D1-T from basic reset monitors.

Is the MAX6386XS29D1-T pin-compatible with other devices in the MAX6381–MAX6390 family, and which packages share the same footprint?

The MAX6386XS29D1-T uses a 4-pin SC70 package (outline 21-0098), which is pin-compatible with all other MAX6384–MAX6390 variants in the XS-prefix 4-pin SC70 configuration - including MAX6384XS29D1-T and MAX6385XS29D1-T. Pin 1 = VCC, Pin 2 = RESET, Pin 3 = MR, Pin 4 = GND. This allows direct substitution within the same package variant without PCB changes, provided reset output type (open-drain) and MR functionality align with system requirements.