Analog Devices Inc./Maxim Integrated MAX6347XR44

Overview

MAX6347XR44 from Maxim Integrated is an active-high push-pull microprocessor supervisory circuit designed to monitor 4.38V power supplies and assert a reset signal during brownout, power-up, or power-down events. It delivers ultra-low 1µA max supply current, guarantees correct operation down to 1V VCC, provides ≥100ms reset timeout after VCC recovery, and features factory-trimmed 4.38V reset threshold with ±1.5% accuracy at +25°C - used in portable battery-powered controllers requiring reliable, low-power reset assertion.

For engineers reviewing the MAX6347XR44 datasheet, MAX6347XR44 pinout, MAX6347XR44 application, or MAX6347XR44 equivalent, this page details its precise reset threshold behavior, SC70-3 package compatibility, active-high push-pull output drive capability (VOH = 0.8·VCC, VOL = 0.4V), transient immunity up to 200µs at 100mV overdrive, and direct replacement context versus MAX809/MAX810 series.

Technical Context

The MAX6347XR44 implements a precision bandgap-based voltage comparator with hysteresis (9.5mV typical) to detect VCC falling below its 4.38V factory-trimmed threshold. Its internal reset timer ensures a minimum 100ms active-high reset pulse width after VCC rises above threshold, independent of supply ramp rate.

It operates across -40°C to +85°C with 40ppm/°C reset threshold tempco and maintains functional state down to 1V VCC. The push-pull output drives high (VOH ≥ 0.8·VCC at ISOURCE = 500µA) and low (VOL ≤ 0.4V at ISINK = 3.2mA), eliminating external pull-up components required by open-drain alternatives.

Key Specifications

Pinout & Package

MAX6347XR44 is housed in a 3-pin SC70-3 package (2.0mm × 2.1mm × 0.9mm), compatible with SOT23-3 footprint for layout flexibility. Pin 1 = VCC, Pin 2 = RESET (active-high push-pull), Pin 3 = GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TR44D3T and TPS3808G33DBVR, MAX6347XR44 uniquely combines 4.38V precision, active-high push-pull output, and 1µA max ICC in SC70-3 - enabling drop-in replacement in legacy Maxim designs while eliminating pull-up resistors and extending battery life.

Availability

MAX6347XR44 is available at Aetrix Electronics and suitable for industrial controllers, portable medical devices, and automotive body control modules requiring stable component supply, long-term lifecycle support, and lead-free compliance.

Supply support for MAX6347XR44 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 interface applications in industrial, automotive, and computing markets.

The MAX63xx family targets ultra-low-power microprocessor supervision, delivering factory-trimmed reset thresholds, sub-µA quiescent current, and SC70/SOT23 packaging for space- and energy-constrained systems.

FAQ

What is the exact reset threshold voltage of MAX6347XR44?

The MAX6347XR44 has a factory-trimmed reset threshold of 4.38V with ±1.5% tolerance at +25°C. This value is confirmed in Table 1 of the datasheet and applies specifically to the "R44" suffix variant. Over the full -40°C to +85°C range, the threshold drift is limited by a 40ppm/°C tempco, resulting in <±15mV total variation. The MAX6347XR44 uses this precise threshold to reliably monitor 4.38V power rails without external calibration.

Does MAX6347XR44 require an external pull-up resistor on its RESET pin?

No, MAX6347XR44 does not require an external pull-up resistor because it features an active-high push-pull output. Its RESET pin actively drives high (VOH ≥ 0.8·VCC at ISOURCE = 500µA) and low (VOL ≤ 0.4V at ISINK = 3.2mA), eliminating reliance on external components. This distinguishes MAX6347XR44 from open-drain variants like MAX6348XR44 and simplifies PCB layout. The push-pull architecture is explicitly documented in the Pin Description section for MAX6327/MAX6347.

What package type and dimensions does MAX6347XR44 use?

MAX6347XR44 is supplied in a 3-pin SC70-3 package measuring 2.0mm × 2.1mm × 0.9mm, with pin pitch of 0.65mm. This package is footprint-compatible with SOT23-3, allowing flexible layout reuse. The SC70-3 outline is defined in Maxim's package drawing 21-0075, and the device is available in tape-and-reel format only. Lead-free versions are ordered with the "+T" suffix instead of "-T", per the Ordering Information section.

How long is the reset pulse width asserted by MAX6347XR44 after VCC recovers?

MAX6347XR44 asserts its active-high RESET signal for a minimum of 100ms after VCC rises above the 4.38V threshold. This guaranteed timeout is independent of VCC ramp rate and satisfies JEDEC JESD72 power-on reset timing requirements. Typical duration is 185ms at +25°C, extending to 280ms at +85°C, as specified in the Electrical Characteristics table under "Reset Active Timeout Period". This ensures robust initialization of downstream microprocessors.

Is MAX6347XR44 suitable for battery-powered applications with multi-year runtime requirements?

Yes, MAX6347XR44 is optimized for battery-powered applications, drawing a maximum of 1µA supply current across temperature. This ultra-low ICC enables multi-year operation on coin cells such as CR2032 - for example, supporting >10 years of standby in portable medical devices. Its ability to function down to 1.0V VCC further extends usable battery life by maintaining reset integrity during deep discharge. These characteristics are validated in the Electrical Characteristics and Typical Operating Characteristics sections of the MAX6347XR44 datasheet.