Analog Devices Inc./Maxim Integrated MAX6346XR46+

Overview

MAX6346XR46+ from Maxim Integrated is an ultra-low-power, active-low push-pull microprocessor supervisory circuit designed to monitor 4.63V power supplies and assert a reset signal during brownout, power-up, or power-down events. It features a factory-trimmed 4.63V reset threshold (±2.5% over -40°C to +85°C), 100ms minimum reset timeout, 1µA max supply current at 3V, and operates down to 1.2V VCC. It is used in portable battery-powered systems requiring reliable, low-quiescent-power reset supervision.

For engineers reviewing the MAX6346XR46+ datasheet, MAX6346XR46+ pinout, MAX6346XR46+ application, or MAX6346XR46+ equivalent, key selection criteria include its precise 4.63V threshold tolerance, SC70-3 package footprint, push-pull active-low RESET output, immunity to fast VCC transients, and compatibility with 1.2V–5.5V supply rails in space-constrained embedded designs.

Technical Context

The MAX6346XR46+ implements a precision bandgap-based voltage comparator with hysteresis (9.5mV) to detect VCC drops below its 4.63V threshold and hold RESET asserted for ≥100ms after recovery. Its internal timing circuit ensures deterministic reset timeout independent of external components.

It uses a push-pull output stage capable of sourcing 500µA at 0.8·VCC and sinking 1.6mA at ≤0.3V - eliminating need for external pull-up resistors. The device guarantees correct reset state down to VCC = 1.2V and rejects transients up to 100V/µs slew rate.

Key Specifications

Pinout & Package

MAX6346XR46+ is housed in a 3-pin SC70-3 package (outline X3-2, land pattern 90-0208), measuring 2.0mm × 2.1mm × 0.95mm, suitable for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6326XR46+, the MAX6346XR46+ offers guaranteed operation to +85°C and tighter production testing across temperature, making it suitable for extended-temperature industrial and automotive edge nodes; compared with TPS3124E18DBVR, it provides exact 4.63V threshold accuracy without external components and superior noise rejection for 5V-system brownout protection.

Availability

MAX6346XR46+ is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, smart meter communication units, and automotive body control modules requiring stable component supply, RoHS-compliant packaging, and long-term lifecycle support.

Supply support for MAX6346XR46+ 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, communications, computing, and consumer applications.

The MAX6346XR46+ belongs to Maxim's ultra-low-power µP supervisory family, engineered specifically for reliable, component-free reset generation in battery-constrained and thermally demanding embedded systems.

FAQ

What is the exact reset threshold voltage of the MAX6346XR46+ and how does it vary with temperature?

The MAX6346XR46+ has a factory-trimmed nominal reset threshold of 4.63V at +25°C, with guaranteed tolerance of ±2.5% over the full operating temperature range of -40°C to +85°C. Its temperature coefficient is 40ppm/°C, resulting in a maximum deviation of approximately ±11.6mV across the range - well within system-level margin for 5V-supply brownout detection. This precision eliminates need for external calibration.

Does the MAX6346XR46+ require any external components to function as a reset supervisor?

No, the MAX6346XR46+ requires zero external components. Its internal voltage reference, comparator, and 100ms reset timeout timer are fully integrated. The push-pull RESET output drives directly into a microprocessor's reset pin without needing a pull-up resistor - reducing bill-of-materials count, PCB area, and potential failure points in compact designs.

Can the MAX6346XR46+ operate reliably during fast VCC transients, such as those caused by switching regulators or motor drivers?

Yes, the MAX6346XR46+ is specifically designed to reject fast negative-going VCC transients. Its reset comparator ignores glitches shorter than ~20µs when the overdrive (VTH – VCC) is 100mV, and shorter durations at higher overdrive levels. This immunity prevents spurious resets in electrically noisy environments like industrial motor controls or automotive body electronics.

What is the minimum VCC voltage at which the MAX6346XR46+ guarantees correct reset state assertion?

The MAX6346XR46+ guarantees correct reset state (RESET asserted low) for VCC down to 1.2V over the full -40°C to +85°C temperature range. This ensures reliable brownout detection even as the supply decays below the 4.63V threshold and through the final stages of power collapse - critical for orderly shutdown in battery-powered systems.

How does the push-pull output of the MAX6346XR46+ differ from open-drain alternatives like the MAX6348XR46+?

The MAX6346XR46+ features an active-low push-pull RESET output that both sources and sinks current - driving high actively (≥0.8·VCC at 500µA) and low actively (≤0.3V at 1.6mA). In contrast, the MAX6348XR46+ uses an open-drain output requiring an external pull-up resistor. The push-pull architecture simplifies design, reduces component count, and avoids weak pull-up limitations in high-speed or low-voltage µP interfaces.