Analog Devices Inc./Maxim Integrated MAX6314US44D3

Overview

MAX6314US44D3 from Maxim Integrated is a low-power CMOS microprocessor supervisory circuit that monitors V_CC supply voltage and provides bidirectional-reset-compatible active-low RESET output. It features factory-trimmed 4.39V reset threshold, 140ms minimum reset timeout period, ±1.8% threshold accuracy at +25°C, 5µA supply current, and SOT143 package. It is used in portable/battery-powered equipment to ensure reliable µP initialization during power-up, brownout, or manual reset events.

For engineers reviewing the MAX6314US44D3 datasheet, MAX6314US44D3 pinout, MAX6314US44D3 application, or MAX6314US44D3 equivalent, key selection criteria include bidirectional reset compatibility with 68HC11-class µPs, precise 4.39V V_CC monitoring, 140ms reset hold time, immunity to short V_CC transients, and absence of external pullup requirements due to integrated 4.7kΩ resistor + active p-channel pullup.

Technical Context

The MAX6314US44D3 implements a precision voltage-monitoring comparator with laser-trimmed internal resistive divider to detect V_CC falling below 4.39V (±1.8% at +25°C, ±2.5% over -40°C to +85°C), triggering a reset assertion. Its RESET output combines an n-channel pulldown with parallel 4.7kΩ passive pullup and p-channel active pullup enabled for 2µs after release, enabling fast rise time on capacitive reset buses.

It integrates a manual reset input (MR) with 63kΩ internal pullup and glitch rejection (100ns min pulse width), and uses an internal timer to maintain RESET low for ≥140ms after V_CC recovery or MR deassertion. The device operates from 2.5V to 5.5V and draws only 5µA typical supply current.

Key Specifications

Pinout & Package

SOT143 package: 4-pin, surface-mount, -40°C to +85°C operating temperature range, lead-free compatible (replace "-T" with "+T" for RoHS-compliant ordering).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6315US44D3-T, the MAX6314US44D3 eliminates external pullup components and supports bidirectional reset arbitration; compared with TPS3808G33DBVR, it offers higher threshold precision for 4.4V rails, integrated MR debounce, and hardware-level µP reset source identification capability.

Availability

MAX6314US44D3 is available at Aetrix Electronics and suitable for portable/battery-powered equipment, industrial controller monitoring, automotive body control units, and medical diagnostic handsets requiring stable component supply and long-term production continuity.

Supply support for MAX6314US44D3 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 high-performance analog and mixed-signal semiconductor solutions for power, interface, sensing, and timing applications.

The MAX6314 product line delivers precision, low-power microprocessor supervisory circuits optimized for reliable reset generation in battery-constrained and noise-prone embedded systems with bidirectional µP reset requirements.

FAQ

What is the exact reset threshold voltage of the MAX6314US44D3?

The MAX6314US44D3 has a factory-trimmed nominal reset threshold voltage of 4.39V, with ±1.8% accuracy at +25°C and ±2.5% over the full -40°C to +85°C operating temperature range. This value is laser-trimmed during manufacturing and is specific to the "US44" variant in the MAX6314 family, as confirmed in the Ordering Information table.

Does the MAX6314US44D3 require an external pullup resistor on the RESET pin?

No, the MAX6314US44D3 does not require an external pullup resistor. It integrates a 4.7kΩ passive pullup resistor in parallel with an active p-channel transistor, enabling direct connection to bidirectional µP reset pins like those on the 68HC11. This eliminates external components while ensuring fast RESET rise time even with multiple devices on the bus.

What is the minimum reset timeout period for the MAX6314US44D3?

The MAX6314US44D3 has a minimum reset timeout period (t_RP) of 140ms, as indicated by the "D3" suffix in the part number. This guaranteed hold time ensures the microprocessor remains held in reset long enough for power supplies to stabilize and internal clocks to lock, preventing premature execution of corrupted code.

Can the MAX6314US44D3 be used with microprocessors other than the 68HC11?

Yes, the MAX6314US44D3 is compatible with any microprocessor or microcontroller featuring a bidirectional reset I/O pin that accepts active-low reset assertion and supports open-drain-style bus sharing. Its RESET output architecture-combining n-channel pulldown, 4.7kΩ pullup, and active p-channel pullup-is explicitly designed for this class of interface, not limited to the 68HC11.

What is the supply current consumption of the MAX6314US44D3 at +25°C?

The MAX6314US44D3 consumes 5µA typical supply current (I_CC) at +25°C and V_CC = 5.5V with no load, as specified in the Electrical Characteristics table. This ultra-low quiescent current enables multi-year operation in battery-powered applications such as portable instrumentation and handheld medical devices.