Analog Devices Inc./Maxim Integrated MAX6337US16D2

Overview

MAX6337US16D2 from Maxim Integrated is an ultra-low-voltage, open-drain microprocessor supervisory circuit designed to monitor 1.6V power supplies in space-constrained embedded systems. It asserts an active-low RESET signal when VCC falls below 1.60V or upon manual reset, with guaranteed operation down to VCC = 1.0V, 3.3µA supply current, and a 100ms minimum reset timeout period - used in portable instrumentation and battery-powered controllers.

For engineers reviewing the MAX6337US16D2 datasheet, MAX6337US16D2 pinout, MAX6337US16D2 application, or MAX6337US16D2 equivalent, key selection considerations include its open-drain output for bidirectional µP reset interfaces, factory-trimmed 1.60V threshold with ±3% variation over -40°C to +125°C, and SOT143 package compatibility with MAX811/MAX812 and MAX6314/MAX6315.

Technical Context

The MAX6337US16D2 integrates a precision voltage comparator with factory-trimmed 1.60V reset threshold (±1.8% at +25°C, ±3% over full temperature range) and internal debounced manual-reset input with 20kΩ pull-up. Its open-drain RESET output supports wired-OR configurations and interfaces directly with bidirectional reset pins such as those on Motorola 68HC11 microcontrollers.

Reset assertion is immune to fast VCC transients - e.g., a 50mV overdrive rejects transients up to ~25µs - and features guaranteed valid RESET state down to VCC = 1.0V. The device uses no external components and operates across the full industrial temperature range (-40°C to +125°C) with 3.3µA typical ICC at 1.8V.

Key Specifications

Pinout & Package

The MAX6337US16D2 is housed in a 4-pin SOT143 package (3.0mm × 1.6mm × 0.9mm), surface-mount, lead-free compatible (suffix +T), with gull-wing leads and thermal pad not connected internally.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6336US16D2 and MAX811TEUS29D3, the MAX6337US16D2 uniquely supports open-drain interfacing and 1.6V threshold targeting sub-1.8V logic domains, making it the only option for bidirectional reset architectures at this voltage level.

Availability

MAX6337US16D2 is available at Aetrix Electronics and suitable for portable medical instrumentation, automotive body control modules, and industrial sensor nodes requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for MAX6337US16D2 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 management, sensing, and interface applications, with emphasis on reliability and integration for harsh environments.

The MAX6335/MAX6336/MAX6337 family delivers ultra-low-voltage supervisory circuits optimized for space- and power-constrained microprocessor systems requiring precise, factory-trimmed reset thresholds and minimal external components.

FAQ

What is the factory-trimmed reset threshold voltage for MAX6337US16D2?

The MAX6337US16D2 has a factory-trimmed reset threshold of 1.60V, with ±1.8% tolerance at +25°C and ±3% over the full operating temperature range (-40°C to +125°C). This value is laser-trimmed during production and documented in Table 1 of the datasheet; no external adjustment is required. The MAX6337US16D2 is specifically selected for 1.6V supply monitoring in low-voltage digital systems.

Does MAX6337US16D2 support operation below 1.8V, and what is its minimum valid VCC?

Yes, the MAX6337US16D2 is guaranteed to maintain correct reset state down to VCC = 1.0V, unlike the MAX6335/MAX6336 variants which guarantee operation to 0.7V. This makes the MAX6337US16D2 suitable for brownout detection in 1.6V systems where supply may dip near 1.0V before shutdown. Operation below 1.0V is not specified and may result in indeterminate RESET behavior.

What is the function of the MR pin on MAX6337US16D2, and does it require external components?

MR is a debounced manual-reset input that asserts RESET when pulled low. The MAX6337US16D2 includes a 20kΩ internal pull-up resistor, so MR can be left unconnected if unused or tied directly to VCC. A normally open momentary switch between MR and GND provides hardware reset capability without external RC networks. No external components are needed for basic MR functionality in the MAX6337US16D2.

Why does MAX6337US16D2 use an open-drain RESET output instead of push/pull?

The open-drain RESET output on MAX6337US16D2 enables wired-OR reset bus configurations and direct interfacing with microprocessors that have bidirectional reset pins (e.g., Motorola 68HC11). It requires an external pull-up resistor but allows multiple devices to share a common reset line. This architecture is essential in systems where either the supervisor or the µP must be able to assert reset - a capability not supported by push/pull outputs like those in MAX6336US16D2.

Is MAX6337US16D2 pin-compatible with other Maxim supervisory ICs?

Yes, the MAX6337US16D2 is pin-compatible with the MAX811/MAX812 and MAX6314/MAX6315 families in the 4-pin SOT143 package. Pin 1 is GND, Pin 2 is RESET, Pin 3 is MR, and Pin 4 is VCC across all these devices. However, output structure (open-drain vs. push/pull), reset threshold, and timeout differ - so electrical compatibility must be verified per application. The MAX6337US16D2 shares footprint and pinout but not functional equivalence with those parts.