Analog Devices Inc./Maxim Integrated MAX6448UK29L+T

Overview

MAX6448UK29L+T from Maxim Integrated is a single-supply, fixed-threshold microprocessor supervisor IC with one extended-setup manual reset input (MR1) and one immediate-assertion manual reset input (MR2), 2.925V VCC reset threshold, 6.72s MR1 setup period, 140ms min reset timeout, and open-drain active-low RESET output in 5-pin SOT23 package. It prevents nuisance resets in consumer electronics power sequencing and front-panel control circuits.

For engineers reviewing the MAX6448UK29L+T datasheet, MAX6448UK29L+T pinout, MAX6448UK29L+T application, or MAX6448UK29L+T equivalent, key selection concerns include manual reset timing architecture (extended vs. immediate), guaranteed reset validity down to VCC = 1.0V, immunity to <100ns glitches on MR2, and compatibility with 3.3V/5V logic-level pullups for open-drain RESET.

Technical Context

The MAX6448UK29L+T implements dual-mode manual reset logic: MR1 requires a sustained low pulse of 6.72s (L-suffix) to trigger a one-shot 140ms–280ms RESET assertion, while MR2 responds immediately to a rising edge with no setup delay and includes 210ms internal debouncing on deassertion. Its VCC monitor uses a precision bandgap reference with 60ppm/°C tempco and 2×VTH hysteresis.

This device operates across -40°C to +85°C, draws only 6µA typical supply current at 3.6V, guarantees valid RESET output down to VCC = 1.0V, and supports both push-pull and open-drain configurations - MAX6448UK29L+T uses open-drain with internal 50kΩ MR1 pullup and 1µA max RESET leakage when deasserted.

Key Specifications

Pinout & Package

MAX6448UK29L+T is housed in a RoHS-compliant 5-pin SOT23 package (package code U5+1, outline 21-0057), footprint-compatible with standard SOT23-5 land patterns (90-0174). Pin 1 is GND, pin 2 is VCC, pin 3 is MR1, pin 4 is RESET, and pin 5 is MR2.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6448UK29L+T, MAX6447UK29L+T offers identical supervision timing but eliminates the need for an external pullup resistor at the cost of reduced interface flexibility, while MAX6444US29L+T reduces pin count and package size but sacrifices MR2 functionality essential for dual-mode reset architectures.

Availability

MAX6448UK29L+T is available at Aetrix Electronics and suitable for set-top boxes, consumer audio devices, cable/DSL modems, industrial communication gateways, and medical monitoring equipment requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MAX6448UK29L+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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX6443–MAX6452 family was designed specifically to solve nuisance reset issues in front-panel-controlled electronics by combining precision voltage monitoring with configurable manual reset timing - MAX6448UK29L+T implements the dual-input variant optimized for smart-card and service-recovery use cases.

FAQ

What is the exact reset threshold voltage for MAX6448UK29L+T?

The MAX6448UK29L+T has a factory-trimmed VCC reset threshold of 2.925V, with guaranteed tolerance of ±1.5% over the full -40°C to +85°C temperature range. This value corresponds to the "29" suffix in the part number per Table 1 of the datasheet and is optimized for reliable supervision of nominal 3.3V power rails.

How does the MR2 input on MAX6448UK29L+T differ from MR1?

The MR2 input on MAX6448UK29L+T is edge-triggered and responds immediately to a rising edge with no setup time, while MR1 requires a sustained low pulse of 6.72s (L-suffix). MR2 also features 210ms internal debouncing on the falling edge to prevent false releases during card removal, making it ideal for smart-card detect applications - unlike MR1, which is intended for deliberate user-initiated resets.

Can MAX6448UK29L+T operate with VCC below 1.0V?

No - MAX6448UK29L+T guarantees valid RESET output behavior only down to VCC = 1.0V. Below this voltage, current-sinking capability degrades rapidly and RESET may float. For applications requiring reset assertion down to 0V, a pulldown resistor (e.g., 100kΩ) must be added to the RESET node - but this is only valid for push-pull variants, not the open-drain MAX6448UK29L+T.

What package type and pin count does MAX6448UK29L+T use?

MAX6448UK29L+T uses a 5-pin SOT23 package (package code U5+1, outline 21-0057), with pin 1 = GND, pin 2 = VCC, pin 3 = MR1, pin 4 = RESET, and pin 5 = MR2. It is RoHS-compliant, tape-and-reel packaged, and compatible with standard SOT23-5 footprints (land pattern 90-0174).

Is MAX6448UK29L+T suitable for automotive applications?

MAX6448UK29L+T is rated for -40°C to +85°C operation and meets industrial reliability standards, but it is not AEC-Q100 qualified. For automotive cabin applications, Maxim offers AEC-Q100 qualified variants like MAX6444US16K/V+T - MAX6448UK29L+T should be used only in non-safety-critical, non-under-hood industrial or consumer systems.