Analog Devices Inc./Maxim Integrated MAX6306UK31D1+

Overview

MAX6306UK31D1+ from Maxim Integrated is a 5-pin SOT23 programmable microprocessor supervisory circuit that monitors VCC supply voltage and asserts an active-low push/pull reset output when VCC falls below its factory-set 3.08V threshold (±2.5% over temperature), with a 1ms minimum reset timeout period. It features manual-reset input, guaranteed RESET validity down to VCC = 1V, and immunity to fast transients - used in portable computers and multivoltage embedded systems for reliable power-on and brownout reset generation.

For engineers reviewing the MAX6306UK31D1+ datasheet, MAX6306UK31D1+ pinout, MAX6306UK31D1+ application, or MAX6306UK31D1+ equivalent, key selection considerations include its 3.08V VCC reset threshold, 1ms factory-programmed timeout, SOT23-5 package compatibility, manual-reset capability, and guaranteed operation across 0°C to +70°C industrial temperature range.

Technical Context

The MAX6306UK31D1+ uses an internal factory-trimmed resistor divider to monitor VCC and compare it against a precision 1.23V reference, delivering a nominal 3.08V reset threshold with ±2.5% tolerance over -40°C to +85°C. Its reset generator includes a monostable timer that holds RESET asserted for ≥1ms after all monitored supplies recover.

This device integrates a manual-reset input (MR) with internal 63.5kΩ pull-up, TTL/CMOS-compatible logic thresholds, and glitch rejection of ≤0.1µs. The push/pull RESET output sinks up to 3.2mA at VCC > 4.25V and remains valid down to VCC = 1V - enabling robust reset signaling during partial power collapse.

Key Specifications

Pinout & Package

MAX6306UK31D1+ is housed in a RoHS-compliant, lead-free 5-pin SOT23 package (outline U5+1), optimized for space-constrained PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6306UK31D1+, the D2+ variant extends reset duration for timing-critical peripherals, while TPS3808G33DBVR trades flexibility (no MR/RST IN) for lower quiescent current - making MAX6306UK31D1+ optimal for cost-sensitive, feature-complete 3.3V supervisory needs.

Availability

MAX6306UK31D1+ is available at Aetrix Electronics and suitable for portable computers, industrial controllers, and battery-powered instrumentation requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6306UK31D1+ 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 - serving industrial, computing, and communications markets.

The MAX6305–MAX6313 family delivers programmable, multi-input supervisory circuits targeting cost-sensitive embedded systems needing factory-configured reset thresholds, manual reset, and transient-immune operation in minimal SOT23-5 footprint.

FAQ

What is the exact factory-set reset threshold voltage for MAX6306UK31D1+?

The MAX6306UK31D1+ has a factory-trimmed VCC reset threshold of 3.08V, with ±2.5% tolerance over the full operating temperature range (-40°C to +85°C). This value corresponds to the "31" suffix per Maxim's Table 1, and is implemented via an internal precision resistor divider - no external components required for threshold setting.

Does MAX6306UK31D1+ support manual reset functionality, and how is it implemented?

Yes, MAX6306UK31D1+ includes a dedicated MR (manual-reset) input on pin 4. Pulling MR low forces an immediate reset; RESET remains asserted for the full 1ms timeout after MR returns high. An internal 63.5kΩ pull-up resistor allows direct connection of a momentary switch to ground - eliminating external biasing components.

What is the guaranteed operating voltage range for MAX6306UK31D1+ reset output validity?

The MAX6306UK31D1+ guarantees valid RESET output behavior down to VCC = 1V. Below this level, push/pull drive strength degrades significantly. For applications requiring reset assertion all the way to 0V, a 100kΩ pull-down resistor from RESET to GND is recommended - as documented in Maxim's Application Information section.

How does MAX6306UK31D1+ handle short-duration supply transients?

MAX6306UK31D1+ is designed to ignore fast VCC transients ≤0.1µs in duration, preventing false resets from switching noise or ESD events. Its internal comparator architecture and propagation delay characteristics ensure immunity to glitches that fall within the "no-reset" region defined in the Typical Operating Characteristics graphs (TOC7).

Is MAX6306UK31D1+ pin-compatible with other devices in the MAX6305–MAX6313 family?

Yes, MAX6306UK31D1+ shares the identical SOT23-5 pinout (pin 1 = RESET, pin 2 = GND, pin 3 = RST IN, pin 4 = MR, pin 5 = VCC) with all members of the MAX6305–MAX6313 family. However, functional differences exist - e.g., MAX6305 lacks MR and RST IN, while MAX6307 adds OVRST IN - so electrical compatibility must be verified per application requirements.