Analog Devices Inc./Maxim Integrated MAX6316LUK29CX+

Overview

MAX6316LUK29CX+ from Maxim Integrated is a 5-pin SOT23 microprocessor supervisory circuit with active-low open-drain reset output, 2.93V factory-trimmed reset threshold, 140ms minimum reset timeout, and 25.6s typical watchdog timeout. It monitors VCC supply integrity, provides manual reset input, and asserts reset during brownout, software hang, or external fault conditions in embedded control systems.

For engineers reviewing the MAX6316LUK29CX+ datasheet, MAX6316LUK29CX+ pinout, MAX6316LUK29CX+ application, or MAX6316LUK29CX+ equivalent, key selection criteria include guaranteed reset validity down to VCC = 1V, immunity to sub-4µs negative VCC transients, bidirectional reset compatibility (not applicable to this variant), and lead-free SOT23 packaging for industrial temperature operation (-40°C to +125°C).

Technical Context

The MAX6316LUK29CX+ implements a precision voltage monitor with laser-trimmed resistor divider setting VRST = 2.93V ±2.5% over -40°C to +125°C, and features an internal watchdog timer cleared by WDI edge transitions. Its open-drain RESET output sinks up to 3.2mA at VCC ≥ 4.5V with VOL ≤ 0.4V, requiring an external pullup resistor.

Reset assertion occurs when VCC falls below VRST, MR is pulled low, or WDI remains static beyond tWD = 25.6s (Z-suffix). Reset remains active for tRP = 140ms after VCC rises above VRST or MR releases, ensuring reliable µP initialization during power-up and brownout recovery.

Key Specifications

Pinout & Package

MAX6316LUK29CX+ is housed in a RoHS-compliant 5-pin SOT23 package (2.9mm × 1.6mm × 1.1mm), with gull-wing leads and internally connected substrate tied to VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6316LUK29D+, the MAX6316LUK29CX+ offers shorter reset assertion for faster system boot; versus TPS3808G33DBVR, it provides integrated watchdog and manual reset at the cost of higher quiescent current and open-drain output dependency on external pullup.

Availability

MAX6316LUK29CX+ is available at Aetrix Electronics and suitable for industrial PLC modules, medical infusion pumps, smart energy meters, and ruggedized handheld test instruments requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MAX6316LUK29CX+ 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 industrial, automotive, communications, and computing markets, emphasizing reliability, integration, and performance in harsh environments.

The MAX6316–MAX6322 family was engineered specifically for microprocessor supervision in space-constrained, high-reliability embedded systems requiring guaranteed reset validity, watchdog safety monitoring, and immunity to supply transients.

FAQ

What is the exact reset threshold voltage of MAX6316LUK29CX+ and how tightly is it specified?

The MAX6316LUK29CX+ has a factory-trimmed reset threshold of 2.93V, with tolerance of ±2.5% over the full operating temperature range (-40°C to +125°C). This value is laser-trimmed during manufacturing and confirmed in the Electrical Characteristics table; it corresponds to the "29" suffix per Table 1 in the datasheet, ensuring precise alignment with 3.3V system rails.

Does MAX6316LUK29CX+ support manual reset, and how is the MR pin interfaced?

Yes, MAX6316LUK29CX+ includes a manual reset (MR) input. The MR pin is active-low and features an internal 52kΩ pullup resistor, allowing direct connection to ground via a normally-open momentary switch without external components. It rejects transients down to 100ns and accepts TTL/CMOS logic levels depending on VCC voltage, making it suitable for simple, robust user-initiated reset functionality.

What watchdog timeout period is implemented in MAX6316LUK29CX+ and how is it enabled?

The MAX6316LUK29CX+ implements a 25.6s typical watchdog timeout period, indicated by the "Z" suffix in its ordering code. The watchdog is enabled automatically when the WDI pin is driven with periodic edges; leaving WDI unconnected disables the watchdog function entirely, as the internal timer is serviced by default pulses. No configuration register or external component is required.

How does the open-drain RESET output of MAX6316LUK29CX+ interface with different supply voltages?

The open-drain RESET output of MAX6316LUK29CX+ can be pulled up to any voltage from 1.8V to 6V using an external resistor (e.g., 10kΩ), enabling interoperability across mixed-voltage systems. When asserted, RESET sinks current with VOL ≤ 0.4V at 3.2mA load, ensuring solid logic-low level regardless of pullup voltage - a key advantage over push/pull outputs in multi-rail designs.

Is MAX6316LUK29CX+ qualified for operation at extreme temperatures, and what is its supply voltage limit?

Yes, MAX6316LUK29CX+ is rated for continuous operation from -40°C to +125°C and supports supply voltages from 1.0V to 5.5V. Its reset output remains valid down to VCC = 1.0V, and absolute maximum ratings allow VCC up to +6V. These specifications make it suitable for under-hood automotive auxiliary modules, industrial motor drives, and outdoor utility infrastructure where thermal and voltage margins are critical.