Analog Devices Inc./Maxim Integrated MAX6443US26L

Overview

MAX6443US26L from Maxim Integrated is a single-supply, fixed-threshold microprocessor reset supervisor IC with extended manual reset setup period (6.72s), 2.625V VCC reset threshold, and active-low push-pull RESET output. It monitors VCC only, asserts reset when voltage drops below threshold, holds reset for 210ms typical timeout, and operates over –40°C to +85°C in SOT143 package - used in set-top boxes and DVD players for reliable power-on initialization.

For engineers reviewing the MAX6443US26L datasheet, MAX6443US26L pinout, MAX6443US26L application, or MAX6443US26L equivalent, this page delivers verified electrical specs, exact pin functions, real-world use cases, and validated alternative parts - all confirmed for the precise MAX6443US26L variant with 2.625V threshold and L-suffix 6.72s manual reset timing.

Technical Context

The MAX6443US26L implements a precision bandgap-based voltage monitor with 60ppm/°C tempco and 2×VTH hysteresis, coupled with a digital timer that enforces a fixed 6.72s low assertion on MR1 before generating a one-shot 140ms–280ms RESET pulse. Its internal 50kΩ MR1 pullup enables direct connection to front-panel switches without external components.

It features guaranteed RESET assertion down to VCC = 1.0V, 6µA typical supply current at 3.6V, and immunity to transients ≤20µs when VCC dips 100mV below threshold - making it suitable for brownout-prone consumer electronics where nuisance resets must be eliminated.

Key Specifications

Pinout & Package

Package: 4-pin SOT143 (U4+1), 1.3mm × 2.9mm footprint, lead(Pb)-free, surface-mount.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6443US26L, the MAX6443US26T+ offers faster user reset response but reduced noise immunity, while the TPS3808G12DBVR provides lower current and tighter threshold tolerance but requires added circuitry to replicate the 6.72s debounce - making MAX6443US26L optimal for cost-sensitive, front-panel-driven consumer designs.

Availability

MAX6443US26L is available at Aetrix Electronics and suitable for set-top boxes, DVD players, MP3 players, cable/DSL modems, and industrial equipment requiring stable component supply across extended temperature ranges and long-lifecycle production programs.

Supply support for MAX6443US26L 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, with emphasis on high-reliability, low-power solutions.

The MAX6443–MAX6452 family was engineered specifically for consumer and industrial systems needing robust, glitch-immune reset supervision with user-controllable long-press reset - addressing reliability gaps in front-panel-initiated recovery.

FAQ

What is the exact reset threshold voltage of the MAX6443US26L?

The MAX6443US26L has a factory-trimmed VCC reset threshold of 2.625V, with a maximum deviation of ±0.075V over temperature. This value is defined by the "26" suffix per Table 1 in the datasheet and is guaranteed across the full –40°C to +85°C operating range. The MAX6443US26L uses precision bandgap referencing to maintain stability, with 60ppm/°C tempco.

How does the manual reset function work on the MAX6443US26L?

The MAX6443US26L features a single extended manual reset input (MR1) that requires a minimum 6.72s low assertion (L-suffix) to trigger a one-shot RESET pulse. MR1 includes an internal 50kΩ pullup to VCC, enabling direct connection to a momentary switch. Shorter presses are ignored - preventing nuisance resets - and the internal timer debounces transitions without external components.

Is the RESET output of the MAX6443US26L push-pull or open-drain?

The MAX6443US26L has a push-pull RESET output, as indicated by the absence of "/V" or "/T" in the part number suffix and confirmed in the Ordering Information table. It actively drives low (≤0.3V at 1.2mA sink) and high (≥0.8×VCC), eliminating the need for an external pullup resistor - unlike the MAX6444US26L variant which offers open-drain logic.

What package type and footprint does the MAX6443US26L use?

The MAX6443US26L is supplied in a 4-pin SOT143 package (package code U4+1), measuring 1.3mm × 2.9mm with 0.95mm pitch. It is lead(Pb)-free, RoHS-compliant, and designed for standard reflow soldering. Land pattern #90-0183 applies, and the device is tape-and-reel packaged with a 2500-piece minimum order quantity.

Can the MAX6443US26L operate reliably below 1.8V supply voltage?

Yes - the MAX6443US26L is fully specified down to VCC = 1.0V, with guaranteed RESET assertion and valid logic levels at that voltage. Its supply current remains ultra-low (7µA max at 1.0V), and the push-pull output maintains VOL ≤0.3V when sinking 50µA. This makes the MAX6443US26L suitable for brownout scenarios where other supervisors fail to assert reset.