Analog Devices Inc./Maxim Integrated MAX6307UK44D3

Overview

The MAX6307UK44D3 from Maxim Integrated is a 5-pin SOT23 programmable supervisory IC that monitors VCC (factory-set at 4.38V ±2.5%), an adjustable undervoltage input (RST IN), and an adjustable overvoltage input (OVRST IN) to assert an active-low push/pull RESET output. It features a 140ms minimum reset timeout, 8µA supply current, and guaranteed RESET validity down to VCC = 1V. It is used in multivoltage embedded systems requiring reliable power-on and brownout reset control.

For engineers reviewing the MAX6307UK44D3 datasheet, MAX6307UK44D3 pinout, MAX6307UK44D3 application, or MAX6307UK44D3 equivalent, key selection considerations include its dual external reset inputs (RST IN/OVRST IN), factory-trimmed 4.38V VCC threshold, 140ms timeout, SOT23-5 package compatibility, and immunity to fast VCC transients.

Technical Context

The MAX6307UK44D3 implements a triple-monitoring architecture: internal factory-trimmed resistor divider for VCC supervision at 4.38V, external resistor-divider–based comparator for RST IN (undervoltage), and another for OVRST IN (overvoltage). All three inputs feed into a shared reset generator with a fixed 140ms minimum timeout period (D3).

Its push/pull RESET output guarantees VOL ≤ 0.3V at ISINK = 1.2mA and VOH ≥ 0.8 × VCC at ISOURCE = 150µA, enabling direct drive of µP reset pins without external pull-up. The device operates across VCC = (VTH + 2.5%) to +5.5V - i.e., 4.49V to 5.5V - and remains functional over –40°C to +85°C.

Key Specifications

Pinout & Package

MAX6307UK44D3 is housed in a 5-pin SOT23 package (outline U5+1, land pattern 90-0174), optimized for space-constrained PCB layouts and compatible with standard pick-and-place assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple-input supervisory applications.

Compared with MAX6307UK44D3, MAX6307UK46D3 offers a higher factory-set VCC threshold but identical functionality, while TLV809E43DBZR provides lower-cost basic supervision at the expense of missing RST IN/OVRST IN flexibility and push/pull drive strength.

Availability

MAX6307UK44D3 is available at Aetrix Electronics and suitable for industrial PLC power sequencing, medical infusion pump supply monitoring, automotive body control modules, test equipment power integrity verification, and multivoltage embedded systems requiring stable component supply and long-term lifecycle support.

Supply support for MAX6307UK44D3 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 industrial, communications, computing, and consumer applications, with emphasis on high-reliability, low-power, and small-footprint solutions.

The MAX6305–MAX6313 family was developed specifically for multivoltage system supervision - enabling simultaneous monitoring of primary and auxiliary rails in space- and power-constrained embedded platforms using a single 5-pin IC.

FAQ

What is the exact factory-programmed VCC reset threshold for MAX6307UK44D3?

The MAX6307UK44D3 has a factory-trimmed VCC reset threshold of 4.38V, with ±2.5% tolerance over –40°C to +85°C. This value corresponds to the "44" suffix per Table 1 in the datasheet and is implemented via an internal precision resistor divider - no external components are needed to set this threshold.

Does MAX6307UK44D3 support manual reset functionality?

No, MAX6307UK44D3 does not include a manual reset (MR) input. Unlike MAX6306/MAX6309/MAX6312 variants, the MAX6307/MAX6310/MAX6313 family replaces MR with OVRST IN - providing overvoltage monitoring instead of user-initiated reset. External pushbutton reset requires separate circuitry.

What are the valid operating voltage limits for MAX6307UK44D3?

MAX6307UK44D3 requires VCC between 4.49V and 5.5V. This lower bound derives from its 4.38V threshold plus 2.5% (4.38V × 1.025 ≈ 4.49V). Operation below 4.49V is not guaranteed - unlike some members of the MAX6305–MAX6313 family, it does not function down to 1.0V on VCC.

How is the 140ms reset timeout period implemented in MAX6307UK44D3?

The 140ms minimum reset timeout in MAX6307UK44D3 is factory-programmed and temperature-compensated - no external capacitor or resistor is required. It is fixed per the "D3" suffix (D1 = 1ms, D2 = 20ms, D3 = 140ms, D4 = 1120ms) and remains stable across –40°C to +85°C with <±1% variation.

Can MAX6307UK44D3 monitor a 3.3V rail using its RST IN pin?

Yes, MAX6307UK44D3 can monitor a 3.3V rail via RST IN by configuring an external resistor divider so that the voltage at RST IN falls below 1.23V when the 3.3V rail drops below the desired threshold (e.g., 3.0V). The internal 1.23V reference and ±25nA input leakage enable accurate, low-power monitoring with megohm-level resistors.