Analog Devices Inc./Maxim Integrated MAX6320PUK46BY+T

Overview

MAX6320PUK46BY+T from Maxim Integrated is a 5-pin SOT23 microprocessor supervisory circuit with active-low open-drain reset output, 4.63V factory-trimmed reset threshold, 140ms minimum reset timeout, and 1.6s typical watchdog timeout. It monitors VCC supply integrity and provides manual reset and watchdog functionality for embedded control systems requiring robust power-on/brownout protection.

For engineers reviewing the MAX6320PUK46BY+T datasheet, MAX6320PUK46BY+T pinout, MAX6320PUK46BY+T application, or MAX6320PUK46BY+T equivalent, key selection criteria include its open-drain RESET output compatible with multi-supply systems, guaranteed reset validity down to VCC = 1V, immunity to short negative VCC transients (<4µs at 100mV under threshold), and AEC-Q100 qualification for automotive-adjacent industrial use.

Technical Context

The MAX6320PUK46BY+T implements a precision voltage monitor with factory-laser-trimmed resistive divider setting VRST = 4.63V (±2.5% over -40°C to +125°C), integrated watchdog timer cleared by WDI edge transitions, and manual reset input with internal 52kΩ pullup. Reset assertion occurs on VCC drop below VRST, MR low pulse, or WDI timeout - all triggering a fixed 140ms active-low reset hold time.

Its open-drain RESET output requires an external pullup resistor (e.g., 10kΩ) to any supply ≤6V, enabling level-shifting across voltage domains. The WDI input accepts 50ns minimum pulses and draws ≤160µA average current when actively toggled, with internal servicing if left unconnected.

Key Specifications

Pinout & Package

SOT23-5 package (U5+2A outline, land pattern 90-0174), 5-pin surface-mount device with gull-wing leads, RoHS-compliant lead-free finish (+T suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6320PUK46BY+T, the CY-T variant lacks automotive qualification and RoHS compliance, while TPS3808G33DBVR offers lower ICC but omits watchdog and manual reset - making MAX6320PUK46BY+T uniquely suitable for AEC-Q100-aligned designs requiring full supervisory functionality in 4.63V systems.

Availability

MAX6320PUK46BY+T is available at Aetrix Electronics and suitable for industrial PLC controllers, automotive body control modules, portable medical monitors, and smart energy meters requiring stable component supply with long-term lifecycle support.

Supply support for MAX6320PUK46BY+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) designs precision analog, mixed-signal, and power management ICs for demanding industrial, automotive, and communications applications.

The MAX6316–MAX6322 family delivers highly integrated µP supervisory circuits with factory-trimmed thresholds, configurable reset/watchdog timing, and multiple output types - engineered specifically for robust power sequencing and fault recovery in safety-critical embedded systems.

FAQ

What is the exact reset threshold voltage of MAX6320PUK46BY+T and how tightly is it specified?

The MAX6320PUK46BY+T has a factory-trimmed nominal reset threshold of 4.63V, with tolerance of ±1.5% at +25°C and ±2.5% over the full operating temperature range (–40°C to +125°C). This specification is laser-trimmed during production and documented in Table 1 of the MAX6316–MAX6322 datasheet, ensuring precise brownout detection without external components.

Does MAX6320PUK46BY+T support manual reset functionality, and how is the MR pin configured?

Yes, MAX6320PUK46BY+T includes a manual reset (MR) input on Pin 3. It is active-low, internally pulled up to VCC via a 52kΩ resistor, and asserts reset when driven below its threshold (0.3×VCC for VTH < 4.0V; 0.8V for VTH > 4.0V). MR rejects 100ns glitches and requires ≥1.5µs pulse width at full temperature range - enabling reliable pushbutton reset without external debouncing.

What type of reset output does MAX6320PUK46BY+T provide, and what external components are required?

MAX6320PUK46BY+T features an active-low open-drain RESET output on Pin 1. It requires an external pullup resistor to any supply voltage up to 6V - typically 10kΩ - to define the logic-high state. This architecture enables level translation across voltage domains and supports wired-OR reset buses shared with other devices, unlike push/pull outputs.

How does the watchdog timer in MAX6320PUK46BY+T operate, and what is its timeout period?

The MAX6320PUK46BY+T watchdog timer has a typical timeout period of 1.6s (factory-programmed Y-type). It clears on any rising or falling edge at the WDI pin (Pin 4) and asserts reset if no transition occurs within that period. When WDI is left unconnected, the timer is internally serviced at ~7/8 of the timeout interval, effectively disabling watchdog action without external circuitry.

Is MAX6320PUK46BY+T qualified for automotive applications, and what does the "+T" suffix indicate?

Yes, MAX6320PUK46BY+T is AEC-Q100 qualified (Grade 2), meeting automotive reliability requirements for temperature cycling, humidity, and lifetime testing. The "+T" suffix explicitly denotes lead-free (RoHS-compliant) packaging, distinguishing it from the Pb-based "-T" version. This qualification makes it suitable for under-dash, body control, and ADAS-adjacent systems where extended temperature operation and long-term stability are mandatory.