Analog Devices Inc./Maxim Integrated MAX6443US46L

Overview

MAX6443US46L from Maxim Integrated is a single-supply, fixed-threshold microprocessor reset supervisor IC with extended manual reset setup period (6.72s), 4.63V VCC reset threshold, active-low push-pull RESET output, and guaranteed operation down to VCC = 1.0V. It monitors VCC only, features 6µA supply current, and is used in consumer electronics power sequencing and brownout protection.

For engineers reviewing the MAX6443US46L datasheet, MAX6443US46L pinout, MAX6443US46L application, or MAX6443US46L equivalent, key selection criteria include its precise 4.63V reset threshold, long 6.72s manual reset hold time to prevent nuisance resets, SOT143-4 package compatibility, and push-pull output drive capability without external pullup.

Technical Context

The MAX6443US46L implements a precision bandgap-based voltage monitor for VCC with ±0.065V threshold accuracy over temperature and 60ppm/°C tempco. Its internal timing circuit enforces a fixed 6.72s minimum low-time on MR1 before asserting RESET, rejecting transients shorter than 100ns.

RESET asserts as a one-shot pulse for 140ms (min) upon VCC drop below 4.63V or after MR1 remains low ≥6.72s. The push-pull output guarantees VOL ≤0.3V at ISINK = 50µA and VOH ≥0.8×VCC at ISOURCE = 200µA, enabling direct interface to 1.8V–5.5V µP reset inputs.

Key Specifications

Pinout & Package

MAX6443US46L is housed in a 4-pin SOT143 package (3.0mm × 1.6mm, 0.95mm height) with gull-wing leads, rated for -40°C to +85°C operation and RoHS-compliant lead-free finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6443US46L, MAX6316US46D3+ lacks manual reset capability and requires external pullup, while TPS3808G33DBVR offers lower threshold and no MR1-making MAX6443US46L uniquely suited for 4.63V systems needing robust, bounce-immune front-panel reset control.

Availability

MAX6443US46L is available at Aetrix Electronics and suitable for set-top boxes, DVD players, and cable modems requiring stable component supply, long-term lifecycle support, and guaranteed -40°C to +85°C operation.

Supply support for MAX6443US46L 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, with emphasis on high reliability and low power.

The MAX6443–MAX6452 family was engineered specifically for consumer and industrial electronics requiring immunity to switch bounce and precise voltage monitoring during power-up/down/brownout events.

FAQ

What is the exact reset threshold voltage of the MAX6443US46L?

The MAX6443US46L has a factory-trimmed VCC reset threshold of 4.63V, with a typical tolerance of ±0.065V over the full -40°C to +85°C temperature range. This value is confirmed in the Electrical Characteristics table under "VCC Reset Threshold" with suffix "46", corresponding to 4.625V nominal and 4.63V typical. The device guarantees valid RESET assertion when VCC falls below this level and maintains RESET for ≥140ms after VCC recovers.

Does the MAX6443US46L support manual reset functionality?

Yes, the MAX6443US46L includes a single extended-setup manual reset input (MR1) that requires a minimum low-time of 6.72 seconds (suffix "L") to trigger the RESET output. This long setup period eliminates false resets from mechanical switch bounce or brief user presses. MR1 features an internal 50kΩ pullup to VCC, allowing direct connection to a normally-open pushbutton without external components.

What output type does the MAX6443US46L use for its RESET signal?

The MAX6443US46L uses an active-low push-pull RESET output, meaning it actively drives LOW (≤0.3V at 50µA sink) and actively drives HIGH (≥0.8×VCC at 200µA source) without requiring an external pullup resistor. This differs from open-drain variants like MAX6444 and simplifies interface to microprocessor reset inputs across 1.8V–5.5V logic families.

Can the MAX6443US46L operate reliably at low supply voltages?

Yes, the MAX6443US46L guarantees valid RESET logic states down to VCC = 1.0V, as specified in the Absolute Maximum Ratings and Electrical Characteristics. Its internal circuitry remains functional and RESET output retains defined logic levels (VOL ≤0.3V, VOH ≥0.8×VCC) even at this low voltage, enabling robust brownout detection in battery-powered or energy-harvesting systems.

What package does the MAX6443US46L use and what are its key mechanical properties?

The MAX6443US46L is packaged in a 4-pin SOT143 (also referenced as U4+1), measuring 3.0mm × 1.6mm with 0.95mm maximum height and gull-wing leads. It is lead(Pb)-free, RoHS-compliant, and rated for operation from -40°C to +85°C. The pinout is GND (pin 1), RESET (pin 2), MR1 (pin 3), and VCC (pin 4), matching JEDEC MO-178AC outline 21-0052.