Analog Devices Inc./Maxim Integrated MAX6837HXSD2+T

Overview

MAX6837HXSD2+T from Maxim Integrated is an ultra-low-voltage open-drain active-low microprocessor reset circuit in SC70-4 package, designed to monitor +1.313V supply (H-threshold) with ±2.5% accuracy over temperature and assert reset for 30ms after VCC recovery or MR release. It features debounced manual reset input (MR), 7.5µA typical supply current, and guaranteed reset validity down to VCC = 0.55V - used in portable battery-powered µP systems requiring reliable brownout protection.

For engineers reviewing the MAX6837HXSD2+T datasheet, MAX6837HXSD2+T pinout, MAX6837HXSD2+T application, or MAX6837HXSD2+T equivalent, key selection criteria include its H-suffix 1.313V threshold, D2-suffix 30ms timeout, SC70-4 footprint compatibility, MR debounce capability, and open-drain RESET output enabling bidirectional µP reset interfacing and level-shifting across multiple supply domains.

Technical Context

The MAX6837HXSD2+T implements a precision voltage comparator with internal 444mV reference, comparing VCC against factory-trimmed threshold (1.313V) to trigger reset assertion on undervoltage. Its reset timeout is generated by an internal RC oscillator calibrated to deliver 30ms (D2 option) with ±20% tolerance over -40°C to +85°C.

It integrates a 20kΩ internal pullup on MR, supports CMOS- and open-drain-compatible manual reset triggering, and uses BiCMOS process for low leakage (<25nA at RESET-IN). The open-drain RESET output requires external pullup and remains functional down to VCC = 0.55V while sinking ≥200µA at VOL ≤ 0.2V.

Key Specifications

Pinout & Package

MAX6837HXSD2+T is housed in a 4-pin SC70-4 package (2.0mm × 2.1mm, 0.65mm pitch), RoHS-compliant with lead-free termination (+T suffix).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with MAX6837HXSD2+T, the D3 variant offers longer reset hold time at identical footprint and threshold, while TPS3123E13DBVR trades MR functionality and package compatibility for lower ICC and tighter threshold tolerance - making it suitable only for non-interactive, ultra-low-power monitoring roles.

Availability

MAX6837HXSD2+T is available at Aetrix Electronics and suitable for portable medical devices, industrial sensor nodes, battery-powered wearables, and smart metering modules requiring stable component supply with guaranteed long-term continuity.

Supply support for MAX6837HXSD2+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 in industrial, medical, and communications systems.

The MAX6832–MAX6840 family delivers ultra-low-voltage reset supervision for battery-critical applications, emphasizing minimal ICC, small SC70 packaging, and factory-trimmed thresholds to simplify design-in for portable and energy-harvested systems.

FAQ

What is the exact reset threshold voltage of MAX6837HXSD2+T?

The MAX6837HXSD2+T has a factory-set reset threshold of 1.313V with ±2.5% accuracy over the full -40°C to +85°C operating temperature range. This value is defined by the 'H' suffix in the part number and is trimmed during production to match nominal 1.3V supply rails without external components. The threshold remains stable across VCC variations from 0.55V to 3.6V.

Does MAX6837HXSD2+T support manual reset functionality?

Yes, MAX6837HXSD2+T includes a debounced manual reset input (MR) pin with internal 20kΩ pullup to VCC. Pulling MR low for ≥2µs forces an immediate reset assertion, which remains active for the full 30ms timeout period after MR is released. No external debounce circuitry is required, simplifying system-level reset button implementation.

What package type and footprint does MAX6837HXSD2+T use?

MAX6837HXSD2+T is packaged in a 4-pin SC70-4 (also labeled SOT-323-4) outline measuring 2.0mm × 2.1mm with 0.65mm lead pitch. It is RoHS-compliant and lead-free, indicated by the '+T' suffix. The pinout is GND (pin 1), RESET (pin 2), MR (pin 3), and VCC (pin 4), matching standard SC70-4 land patterns published by Maxim.

Can MAX6837HXSD2+T drive a reset line referenced to a voltage higher than VCC?

Yes, MAX6837HXSD2+T features an open-drain active-low RESET output that can be pulled up to any voltage between 0V and 6.0V - including supplies higher than its own VCC (e.g., 3.3V or 5V). This enables level-shifting and shared reset busing across multiple voltage domains, a key advantage over push-pull reset supervisors.

What is the guaranteed minimum VCC level at which MAX6837HXSD2+T maintains valid reset output?

MAX6837HXSD2+T guarantees valid reset output down to VCC = 0.55V for active-low assertion. Below this, the internal output stage ceases sinking current. For applications requiring reset validity to 0V, a 100kΩ pulldown resistor on the RESET line is recommended - a design practice explicitly documented in Maxim's application notes for this device.