Analog Devices Inc./Maxim Integrated MAX6323CUT46+

Overview

MAX6323CUT46+ from Maxim Integrated is a microprocessor supervisory circuit with windowed (min/max) watchdog, push-pull RESET output, and precision +4.63V reset threshold (±2.5% accuracy). It monitors VCC supply integrity, detects out-of-window WDI pulse timing faults, and asserts RESET down to VCC = +1.2V - used in automotive engine control units for fail-safe boot sequencing and brownout recovery.

For engineers reviewing the MAX6323CUT46+ datasheet, MAX6323CUT46+ pinout, MAX6323CUT46+ application, or MAX6323CUT46+ equivalent, key selection criteria include its factory-trimmed 300ms slow watchdog timeout (C-suffix), 15ms fast timeout, 23µA typical supply current, and guaranteed operation across –40°C to +125°C.

Technical Context

The MAX6323CUT46+ implements a dual-threshold watchdog architecture that triggers WDPO on either fast faults (WDI falling edges <15ms apart) or slow faults (no WDI edge >300ms), with glitch immunity of 100ns on MR and WDI inputs. Its internal reset comparator guarantees valid RESET assertion even as VCC decays to +1.2V, and the push-pull output drives CMOS loads directly without external pullup.

It uses laser-trimmed thresholds: nominal reset voltage is +4.63V (UT46 suffix), and watchdog timing is fixed at C-window (tWD1 = 10–15ms fast, tWD2 = 300–450ms slow). The device operates from 1.2V to 5.5V, draws only 23µA typical ICC, and features debounced MR input with 1µs minimum pulse width.

Key Specifications

Pinout & Package

MAX6323CUT46+ is housed in a 6-pin SOT23 package (package code U6-1, outline 21-0058), with 1.6mm × 2.9mm footprint and 0.95mm height - compatible with standard high-volume automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6324CUT46+, the MAX6323CUT46+ offers direct-drive push-pull RESET - eliminating pullup resistors and reducing layout complexity. Versus TPS3808G33DBVR, it delivers higher-voltage supervision (+4.63V), tighter threshold accuracy (±2.5% vs ±3%), and critical windowed watchdog functionality essential for ASIL-B/C automotive and medical systems.

Availability

MAX6323CUT46+ is available at Aetrix Electronics and suitable for automotive engine control, industrial programmable logic controllers, and medical infusion pump designs requiring stable component supply across extended temperature and long product lifecycles.

Supply support for MAX6323CUT46+ 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 demanding industrial, automotive, and medical applications.

The MAX6323/MAX6324 family delivers high-accuracy, windowed watchdog supervision for safety-critical µP systems - engineered specifically for automotive ECU, industrial control, and medical device manufacturers needing guaranteed reset behavior and fault-tolerant timing supervision.

FAQ

What is the exact reset threshold voltage of MAX6323CUT46+ and how tightly is it specified?

The MAX6323CUT46+ has a nominal reset threshold of +4.63V, with guaranteed limits of +4.50V (minimum) and +4.75V (maximum) across –40°C to +125°C. This ±2.5% accuracy is achieved via laser trimming and ensures robust power-on reset for +5V systems without external calibration. The MAX6323CUT46+ datasheet specifies this value in the Electrical Characteristics table under "Reset Threshold Voltage" for UT46 suffix.

Does MAX6323CUT46+ support windowed (min/max) watchdog functionality, and what are its timeout values?

Yes, MAX6323CUT46+ implements true windowed watchdog supervision: fast timeout is 10–15ms (detects premature WDI pulses), and slow timeout is 300–450ms (detects missed pulses). These values correspond to the "C" suffix in the part number and are factory-trimmed - confirmed in the Watchdog Timeout table of the MAX6323CUT46+ datasheet.

Can MAX6323CUT46+ assert a valid RESET output when VCC drops below 2.0V?

Yes, MAX6323CUT46+ guarantees valid RESET assertion down to VCC = +1.2V - meaning it continues to sink current and hold RESET low even as supply voltage collapses. This is critical for safe shutdown in automotive and medical applications. Below +1.2V, the RESET output becomes high-impedance, but the MAX6323CUT46+ specification explicitly covers operation across the full 1.2V–5.5V range.

What is the function of the WDPO pin on MAX6323CUT46+, and how is it used in system design?

The WDPO (Watchdog Pulse Output) pin on MAX6323CUT46+ is an open-drain output that pulses low for 1ms upon detection of either a fast or slow watchdog fault. It operates independently of RESET and is only active when RESET is high. In system design, WDPO can drive an NMI input for non-maskable interrupt handling or be looped back to MR to trigger a full 100ms RESET assertion - both configurations are documented in the MAX6323CUT46+ application circuits.

Is MAX6323CUT46+ qualified for automotive applications, and what packaging does it use?

MAX6323CUT46+ is not AEC-Q100 qualified - only specific variants like MAX6324HUT44/V+T carry that qualification. However, it operates across –40°C to +125°C and uses a lead-free 6-pin SOT23 package (U6-1 outline), making it suitable for under-hood industrial and commercial automotive subsystems where full AEC-Q100 is not mandated. The "+" suffix confirms RoHS-compliant, lead-free construction.