Analog Devices Inc./Maxim Integrated MAX6307UK46D3-T

Overview

The MAX6307UK46D3-T from Maxim Integrated is a 5-pin SOT23 programmable supervisory IC that monitors VCC (factory-set 4.6V threshold), an adjustable undervoltage input (RST IN), and an adjustable overvoltage input (OVRST IN) to assert reset during power faults. It features 140ms minimum reset timeout, 8µA supply current, and guaranteed RESET validity down to VCC = 1V. It is used in multivoltage embedded systems requiring reliable brownout and transient immunity.

For engineers reviewing the MAX6307UK46D3-T datasheet, MAX6307UK46D3-T pinout, MAX6307UK46D3-T application, or MAX6307UK46D3-T equivalent, key selection criteria include its dual adjustable reset inputs, factory-trimmed 4.6V VCC threshold with ±2.5% tolerance over temperature, 140ms timeout, open-drain active-low RESET output, and SOT23-5 package compatibility with space-constrained PCB layouts.

Technical Context

The MAX6307UK46D3-T implements a triple-monitor architecture: internal factory-trimmed resistor divider for VCC supervision at 4.6V nominal, external resistor-programmable RST IN for secondary undervoltage detection, and OVRST IN for overvoltage monitoring-each referenced to a 1.23V internal bandgap. Its reset generator uses a precision RC timer to enforce a guaranteed minimum 140ms timeout after all monitored voltages return to regulation.

It employs glitch-immune comparator design with built-in hysteresis (2.5mV on RST IN/OVRST IN, 2×VTH on VCC) and supports manual reset via MR pin with 63.5kΩ internal pull-up. The open-drain RESET output operates across VCC = 1.0V to 5.5V and sinks ≥3.2mA at VCC > 4.25V.

Key Specifications

Pinout & Package

Package: SOT23-5, surface-mount, RoHS-compliant lead-free option available (+T suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6307UK46D2-T and TPS3808G33DBVR, the MAX6307UK46D3-T uniquely provides 140ms timeout plus dual adjustable inputs for multirail over/undervoltage protection in a single SOT23-5 package-enabling compact, high-integrity supervision where timing and flexibility are critical.

Availability

MAX6307UK46D3-T is available at Aetrix Electronics and suitable for industrial PLCs, medical infusion pumps, automotive body control modules, telecom remote radio units, and multivoltage embedded systems requiring stable component supply across extended temperature and long production lifecycles.

Supply support for MAX6307UK46D3-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 demanding industrial, medical, and communications applications.

The MAX6305–MAX6313 family delivers highly integrated, low-power supervisory circuits optimized for multivoltage system monitoring with factory-programmable thresholds and flexible reset configurations.

FAQ

What is the exact factory-programmed VCC reset threshold for MAX6307UK46D3-T?

The MAX6307UK46D3-T has a factory-programmed VCC reset threshold of 4.6V nominal, with guaranteed tolerance of ±2.5% over the full operating temperature range (-40°C to +85°C). This value is laser-trimmed during production and documented in Table 1 of the MAX6305–MAX6313 datasheet. The "46" in the part number directly encodes the 4.6V threshold, and the device asserts reset when VCC falls below this level.

Does MAX6307UK46D3-T support overvoltage monitoring, and how is it implemented?

Yes, the MAX6307UK46D3-T supports overvoltage monitoring via its dedicated OVRST IN pin (Pin 3). This input compares an external voltage-set by a resistor divider-to an internal 1.23V reference. When the divided voltage exceeds 1.23V, the comparator triggers reset. Unlike the fixed VCC monitor, OVRST IN enables user-defined overvoltage thresholds for secondary rails or auxiliary supplies, making MAX6307UK46D3-T suitable for asymmetric multivoltage supervision.

What is the function of the MR pin on MAX6307UK46D3-T, and does it require external components?

On the MAX6307UK46D3-T, the MR (Manual Reset) pin (Pin 4) provides hardware-initiated reset capability. A logic-low pulse ≥1.5µs asserts RESET for the full timeout period (140ms min). No external components are required: the pin features a 63.5kΩ internal pull-up resistor, allowing direct connection to a momentary switch (to GND) or TTL/CMOS logic. In noisy environments, a 0.1µF capacitor from MR to GND adds immunity-no pull-down or series resistor is needed for basic operation.

Can MAX6307UK46D3-T operate reliably during deep brownout conditions?

Yes, the MAX6307UK46D3-T guarantees valid RESET assertion down to VCC = 1.0V, as confirmed in the Electrical Characteristics table. Its open-drain RESET output remains functional and sinks ≥500µA even at 1.0V, ensuring deterministic reset signaling during severe brownouts. However, below 1.0V, output drive capability degrades; for applications requiring reset validity to 0V, an external 100kΩ pull-down resistor on RESET is recommended per Maxim's Application Information section.

How does the 140ms reset timeout period of MAX6307UK46D3-T get enforced, and is it temperature-stable?

The 140ms minimum reset timeout in MAX6307UK46D3-T is generated by an internal precision RC oscillator and timer circuit, factory-programmed via the "D3" suffix. Typical variation is ±20% over temperature, with normalized timeout stability of ±1% from -40°C to +85°C (per Typical Operating Characteristics Figure 6). This ensures consistent hold time across environmental extremes without external capacitors-critical for meeting µP reset timing requirements in industrial and automotive applications.