Analog Devices Inc./Maxim Integrated MAX6348UR42

Overview

MAX6348UR42 from Maxim Integrated is an open-drain, active-low microprocessor supervisory circuit designed to monitor 4.2V power supplies in embedded systems. It asserts reset when VCC falls below 4.200V (±1.5% at +25°C), maintains reset for ≥100ms after VCC recovers, draws ≤1µA supply current, and operates from 1.2V to 5.5V over –40°C to +85°C - ideal for battery-powered µP reset management.

For engineers reviewing the MAX6348UR42 datasheet, MAX6348UR42 pinout, MAX6348UR42 application, or MAX6348UR42 equivalent, this page delivers verified electrical behavior, SOT23-3 package integration details, reset timing compliance, and direct alternatives for portable and industrial control designs requiring ultra-low-power, factory-trimmed voltage monitoring.

Technical Context

The MAX6348UR42 implements a precision bandgap-based reset comparator with 4.200V factory-trimmed threshold, ±2.5% tolerance over –40°C to +85°C, and 40ppm/°C tempco. Its open-drain RESET output supports bidirectional µP interfaces (e.g., Motorola 68HC11) via external pull-up and tolerates VCC transients up to 200µs at 100mV overdrive.

It guarantees correct reset state down to VCC = 1.2V, features 6.3mV hysteresis for noise immunity, and ignores fast negative-going VCC glitches - enabling reliable brownout detection without external components in space-constrained SOT23-3 layouts.

Key Specifications

Pinout & Package

MAX6348UR42 is housed in a 3-pin SOT23-3 package (JEDEC MO-178AA), footprint-compatible with industry-standard µP reset ICs and optimized for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6348UR42, MAX6328UR42 sacrifices industrial temperature coverage for lower cost, while TPS3808G33DBVR changes both threshold and output architecture - making MAX6348UR42 uniquely suited for 4.2V open-drain reset in extended-temperature portable and industrial edge devices.

Availability

MAX6348UR42 is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, smart meter communication units, and automotive body control modules requiring stable component supply across global production volumes.

Supply support for MAX6348UR42 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, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX63xx family delivers ultra-low-power, factory-trimmed supervisory circuits targeting battery-operated and space-constrained embedded systems needing reliable, no-component reset functionality.

FAQ

What is the exact reset threshold voltage of MAX6348UR42 and how tightly is it specified?

The MAX6348UR42 has a factory-trimmed reset threshold of 4.200V with ±1.5% tolerance at +25°C and ±2.5% over –40°C to +85°C. This specification is guaranteed per datasheet Electrical Characteristics table, and the "R42" suffix explicitly denotes the 4.200V variant within the MAX6348 family. The device uses laser-trimmed resistors to achieve this accuracy without external calibration.

Does MAX6348UR42 support operation at VCC below 2.0V, and what is its minimum functional supply voltage?

Yes, MAX6348UR42 remains fully functional down to VCC = 1.2V across the full –40°C to +85°C temperature range. At 1.2V, it continues to assert RESET correctly when VCC drops below 4.200V and maintains valid output leakage (<0.1µA) - enabling robust reset assertion even during severe brownout conditions where other supervisors fail.

How does the open-drain output of MAX6348UR42 differ from push-pull versions like MAX6347UR42, and why choose it?

The MAX6348UR42 features an open-drain RESET output requiring an external pull-up resistor, unlike the push-pull MAX6347UR42. This enables wired-OR reset busing, bidirectional µP interface (e.g., Motorola 68HC11), and flexible voltage-level translation - critical in multi-rail systems where RESET must be shared across different logic domains without contention.

Is MAX6348UR42 pin-compatible with legacy Maxim reset ICs such as MAX809 or MAX810?

Yes, MAX6348UR42 is pin-compatible with MAX809 and MAX810 in the SOT23-3 package: Pin 1 = GND, Pin 2 = RESET (open-drain), Pin 3 = VCC. This allows drop-in replacement in existing layouts, provided the reset threshold (4.200V) and open-drain behavior match system requirements - no PCB changes required.

What is the maximum transient duration that MAX6348UR42 can ignore without asserting reset, and under what condition?

At a reset threshold overdrive of 100mV (i.e., VCC = 4.100V), MAX6348UR42 ignores transients up to 200µs, as shown in Figure 4 of the datasheet. This immunity is measured in SC70 packages but applies equivalently to the SOT23-3 MAX6348UR42, ensuring robust operation in electrically noisy environments like motor drives or switching power supplies.