Analog Devices Inc./Maxim Integrated MAX6314US44D1+T

Overview

MAX6314US44D1+T from Maxim Integrated is a low-power CMOS microprocessor supervisory circuit designed to monitor VCC supply voltage and assert a bidirectional reset signal for µPs with bidirectional reset I/Os (e.g., Motorola 68HC11). It features a factory-trimmed 4.39V reset threshold, 1ms 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 requiring reliable power-on reset and brownout protection.

For engineers reviewing the MAX6314US44D1+T datasheet, MAX6314US44D1+T pinout, MAX6314US44D1+T application, or MAX6314US44D1+T equivalent, key selection criteria include bidirectional RESET compatibility, precise 4.39V threshold tolerance, 1ms timeout timing, immunity to short VCC transients, and absence of external components for manual reset debounce.

Technical Context

The MAX6314US44D1+T implements a precision voltage-monitoring comparator with laser-trimmed internal resistive divider to set its 4.39V reset threshold, and integrates a monostable timer for fixed 1ms reset assertion after VCC recovery or MR deassertion. Its RESET output combines an n-channel pulldown, p-channel active pullup, and 4.7kΩ passive pullup - enabling direct interface to bidirectional µP reset pins without external components.

This architecture eliminates need for external pullup resistors while ensuring fast RESET rise time (<35µs typical) under capacitive bus loading, critical for multi-device reset buses. The device operates across -40°C to +85°C, draws only 5µA at +25°C, and remains functional down to VCC = 1.0V with guaranteed RESET sinking capability.

Key Specifications

Pinout & Package

SOT143 (4-pin, surface-mount) package with exposed pad option; compact 2.9mm × 1.5mm footprint, 1.0mm height, lead-free compliant (indicated by "+T" suffix).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6314US44D1+T, MAX6315US44D1+T requires external pullup and cannot drive bidirectional reset lines, while TPS3808G33DBVR offers lower current but mismatches the 4.39V threshold and eliminates MR integration - making MAX6314US44D1+T uniquely suited for 4.39V, bidirectional, and manually resettable µP systems.

Availability

MAX6314US44D1+T is available at Aetrix Electronics and suitable for portable medical monitors, industrial PLC controllers, and smart energy meters requiring stable component supply, long-term lifecycle support, and lead-free compliance.

Supply support for MAX6314US44D1+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 industrial, automotive, and communications applications.

The MAX6314 series was developed specifically for microprocessor supervision in resource-constrained systems requiring bidirectional reset compatibility, factory-trimmed thresholds, and zero-external-component operation.

FAQ

What is the exact reset threshold voltage of the MAX6314US44D1+T?

The MAX6314US44D1+T has a factory-trimmed nominal reset threshold of 4.39V, with ±1.8% accuracy at +25°C and ±2.5% over the full -40°C to +85°C temperature range. This value is laser-trimmed during production and specified in the Ordering Information table - it is not adjustable or user-configurable. The threshold is monitored directly on the VCC pin using an internal precision voltage divider.

Does the MAX6314US44D1+T require an external pullup resistor on the RESET pin?

No, the MAX6314US44D1+T does not require an external pullup resistor on the RESET pin. It integrates a 4.7kΩ passive pullup resistor in parallel with a p-channel active pullup transistor - this configuration is explicitly designed to eliminate external components while ensuring fast rise time on capacitive reset buses. The internal pullup is automatically disconnected when RESET is asserted to minimize current consumption.

How does the manual reset (MR) function work on the MAX6314US44D1+T?

The MR pin on the MAX6314US44D1+T is an active-low input with a built-in 63kΩ pullup resistor. Pulling MR low asserts RESET immediately, and RESET remains asserted for the full 1ms timeout period after MR returns high. No external debounce circuitry is needed - the internal design filters short pulses (<100ns), and a 0.1µF capacitor to ground can be added for enhanced noise immunity in electrically noisy environments.

Is the MAX6314US44D1+T pin-compatible with the MAX811?

Yes, the MAX6314US44D1+T is pin-compatible with the MAX811 in the SOT143 package - both share identical pinout (VCC, MR, RESET, GND) and physical footprint. However, the MAX6314US44D1+T differs functionally: it features a bidirectional RESET output with integrated pullup, whereas the MAX811 has open-drain RESET. Direct substitution requires verifying that the host µP supports bidirectional reset signaling.

What is the minimum VCC voltage at which the MAX6314US44D1+T guarantees RESET output sinking capability?

The MAX6314US44D1+T guarantees RESET output sinking capability down to VCC = 1.0V, with VOL ≤ 0.4V at ISINK = 0.5mA (per Electrical Characteristics table). Below 1.0V, RESET transitions to high-impedance state - for applications requiring valid RESET down to 0V, a 100kΩ external pull-down resistor on the RESET line is recommended to prevent floating states.