Analog Devices Inc./Maxim Integrated MAX6314US29D2+T

Overview

MAX6314US29D2+T from Maxim Integrated is a low-power CMOS microprocessor supervisory circuit that monitors V_CC supply voltage and asserts a bidirectional reset signal when voltage falls below 2.93V or manual reset is triggered. It features a factory-trimmed 2.93V reset threshold, 20ms minimum reset timeout period, 5µA supply current, and SOT143 package. It is designed for reliable power-up/power-down sequencing in 68HC11-compatible µP systems.

For engineers reviewing the MAX6314US29D2+T datasheet, MAX6314US29D2+T pinout, MAX6314US29D2+T application, or MAX6314US29D2+T equivalent, key selection criteria include bidirectional RESET compatibility, ±2.5% reset threshold accuracy over temperature, immunity to short V_CC transients, and absence of external component requirements for pullup or debounce.

Technical Context

The MAX6314US29D2+T integrates a precision voltage comparator with laser-trimmed resistive divider to detect V_CC drops below 2.93V, combined with an internal timer that holds RESET active for ≥20ms after recovery. Its bidirectional RESET output includes a 4.7kΩ passive pullup in parallel with a p-channel active pullup transistor, enabling fast rise time (<350ns at 100pF) even with multiple devices on the reset bus.

MR input incorporates a 63kΩ internal pullup and accepts logic-low manual reset pulses ≥1µs wide, with 100ns glitch rejection. The device operates across -40°C to +85°C, draws only 5µA at +25°C, and remains functional down to V_CC = 1.0V while guaranteeing RESET sink capability.

Key Specifications

Pinout & Package

SOT143 package: 4-pin, single-ended, lead-free (RoHS-compliant), -40°C to +85°C operating range.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6314US29D2+T, MAX6315US29D2+T removes bidirectional capability but simplifies layout for open-drain-only systems, while TPS3808G18DBVR offers lower current and adjustable timing at the cost of design flexibility and MR functionality.

Availability

MAX6314US29D2+T is available at Aetrix Electronics and suitable for industrial controllers, portable medical devices, automotive body electronics, smart energy meters, and battery-backed instrumentation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6314US29D2+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) is a semiconductor company specializing in analog, mixed-signal, and power management ICs for industrial, communications, and computing applications.

The MAX6314 family delivers precision, low-power µP supervision with bidirectional reset capability, targeting applications where reset source identification and minimal external components are critical-especially in legacy 68HC11-based and resource-constrained embedded systems.

FAQ

What is the exact reset threshold voltage for MAX6314US29D2+T?

The MAX6314US29D2+T has a factory-trimmed nominal reset threshold of 2.93V, with ±2.5% accuracy over the full -40°C to +85°C operating temperature range. This value is laser-trimmed during production and does not require external calibration. The threshold is referenced to the V_CC pin and remains stable against supply ripple and transient noise up to 100ns duration.

Does MAX6314US29D2+T support bidirectional reset communication with the 68HC11 µP?

Yes, MAX6314US29D2+T is explicitly designed for bidirectional reset compatibility with the Motorola 68HC11 and other µPs featuring bidirectional reset I/O. Its RESET pin combines a 4.7kΩ pullup resistor and a p-channel active pullup transistor, enabling the µP to drive RESET low and detect external assertion-allowing software to distinguish between self-initiated and supervisor-initiated resets using the standard two-E-clock sampling method.

What is the minimum reset timeout period specified for MAX6314US29D2+T?

The MAX6314US29D2+T provides a minimum reset timeout period of 20ms after V_CC rises above 2.93V or after the MR input is deasserted. This guaranteed minimum ensures sufficient hold time for microprocessor initialization across all process corners and temperature extremes, meeting JEDEC JESD78 requirements for robust reset assertion in commercial and industrial environments.

Can MAX6314US29D2+T operate with V_CC below 2.93V?

Yes, MAX6314US29D2+T operates down to V_CC = 1.0V and continues to assert RESET as long as V_CC remains below 2.93V. Below 1.0V, the RESET output becomes high-impedance (open-circuit), but the device remains functional and reasserts RESET immediately upon V_CC rising above 1.0V. This behavior ensures fail-safe reset during deep brownout conditions without requiring external pull-down components.

Is an external pullup resistor required for the RESET pin of MAX6314US29D2+T?

No, an external pullup resistor is not required for the RESET pin of MAX6314US29D2+T. The device integrates both a 4.7kΩ passive pullup resistor and a p-channel active pullup transistor, enabling fast rise times (<350ns into 100pF) and eliminating the need for external components. This integrated solution reduces BOM count, PCB area, and potential failure points while supporting bidirectional reset arbitration in multi-device systems.