Analog Devices Inc./Maxim Integrated MAX6823LUK+T

Overview

MAX6823LUK+T from Maxim Integrated is a low-voltage microprocessor supervisory IC in 5-pin SOT23 package, featuring push-pull active-low RESET output, 4.63V reset threshold, 140ms minimum reset timeout, 1.6s watchdog timeout, and manual reset input. It monitors VCC for brownout detection and asserts reset during power-up, power-down, or code faults in embedded controllers and portable equipment.

For engineers reviewing the MAX6823LUK+T datasheet, MAX6823LUK+T pinout, MAX6823LUK+T application, or MAX6823LUK+T equivalent, this device supports critical µP monitoring in battery-powered systems where guaranteed reset validity down to VCC = +1.0V, immunity to short negative VCC transients, and no external components are essential selection criteria.

Technical Context

The MAX6823LUK+T integrates voltage monitoring, watchdog timer, and manual reset functions in a single BiCMOS IC. Its reset generator triggers on VCC falling below 4.63V (±3% over –40°C to +125°C), holds RESET asserted for ≥140ms after VCC recovers, and guarantees correct output state down to VCC = +1.0V.

A dedicated WDI input accepts 50ns minimum pulses to clear the 1.6s watchdog timer; MR input features internal 50kΩ pullup and 200ns MR-to-reset delay. The push-pull active-low RESET output sinks up to 3.2mA at VCC ≥ 4.25V with VOL ≤ 0.4V.

Key Specifications

Pinout & Package

MAX6823LUK+T is housed in a RoHS-compliant 5-pin SOT23-5 package (outline 21-0057, land pattern 91-0174), measuring 2.9mm × 1.6mm × 1.1mm, suitable for space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6823LUK+T, MAX6822LUK+T offers open-drain flexibility at the cost of added component count, while MAX6326UR29D3+T reduces functionality and package size but eliminates critical fault-detection capabilities required for robust embedded operation.

Availability

MAX6823LUK+T is available at Aetrix Electronics and suitable for set-top boxes, embedded controllers, and portable/battery-powered equipment requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX6823LUK+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 designs precision analog and mixed-signal semiconductor solutions for industrial, computing, communications, and consumer markets.

The MAX682x family delivers integrated µP supervision-combining voltage monitoring, watchdog, and manual reset-to replace discrete solutions in space- and power-constrained embedded systems.

FAQ

What is the reset threshold voltage of MAX6823LUK+T?

The MAX6823LUK+T has a factory-programmed reset threshold of 4.63V, with ±3% tolerance over the full –40°C to +125°C temperature range. This value is fixed by the "L" suffix and ensures reliable detection of brownout conditions in +5V systems. The threshold is referenced to the VCC pin and remains valid down to VCC = +1.0V, making MAX6823LUK+T suitable for applications with marginal supply stability.

Does MAX6823LUK+T include a watchdog timer and manual reset input?

Yes, MAX6823LUK+T integrates both a 1.6s watchdog timer (with 50ns minimum WDI pulse detection) and an active-low manual reset input (MR) with internal 50kΩ pullup. The MR input asserts reset when pulled low and holds it for the full 140ms timeout after release. These features are confirmed in the Selector Guide and Pin Description sections of the MAX6821–MAX6825 datasheet, distinguishing MAX6823LUK+T from variants like MAX6824/MAX6825 that omit one or both functions.

What package type and footprint does MAX6823LUK+T use?

MAX6823LUK+T is supplied in a 5-pin SOT23-5 package (package code U5-1, outline 21-0057, land pattern 91-0174), measuring 2.9mm × 1.6mm × 1.1mm. This RoHS-compliant, surface-mount package is identical across the MAX6821–MAX6825 series and supports reflow soldering per JEDEC J-STD-020. The pinout is standardized: Pin 1 = RESET, Pin 2 = GND, Pin 3 = WDI, Pin 4 = MR, Pin 5 = VCC.

How does the RESET output of MAX6823LUK+T behave during power-up?

During power-up, MAX6823LUK+T asserts its push-pull active-low RESET output until VCC rises above 4.63V and remains asserted for a minimum of 140ms thereafter. This ensures the connected microprocessor completes internal initialization before release. The RESET output transitions cleanly between logic states with VOL ≤ 0.4V (at 3.2mA sink) and VOH ≥ 0.8×VCC (at 800µA source), eliminating need for external level-shifting or pullup components.

Can MAX6823LUK+T operate with supply voltages below 2.5V?

Yes, MAX6823LUK+T operates with VCC as low as +1.2V over the full –40°C to +125°C range, and its RESET output remains valid down to VCC = +1.0V. However, the 4.63V reset threshold means it is intended for monitoring higher-voltage rails (e.g., +5V or +3.3V systems). For sub-2.5V applications, other suffixes like "W" (1.67V) or "V" (1.58V) would be appropriate-but MAX6823LUK+T itself is optimized for +5V domain supervision.