Analog Devices Inc./Maxim Integrated MAX6346UR46

Overview

MAX6346UR46 from Maxim Integrated is a push-pull, active-low microprocessor supervisory circuit designed to monitor 4.63V power supplies and assert a reset signal during brownout or power-up conditions. It features factory-trimmed 4.63V reset threshold (±2.5% over -40°C to +85°C), 100ms minimum reset timeout, ultra-low 1µA max supply current, and operates down to 1.2V VCC. It is used in portable battery-powered equipment requiring reliable power-on reset for critical µP systems.

For engineers reviewing the MAX6346UR46 datasheet, MAX6346UR46 pinout, MAX6346UR46 application, or MAX6346UR46 equivalent, key selection criteria include its precise 4.63V reset threshold, SOT23-3 package compatibility, push-pull active-low RESET output, guaranteed operation down to 1.2V VCC, and immunity to fast VCC transients-critical for embedded controllers and intelligent instrumentation.

Technical Context

The MAX6346UR46 implements a precision voltage comparator with hysteresis (9.5mV) and internal timing circuitry to guarantee ≥100ms reset assertion after VCC rises above the 4.63V threshold. Its reset comparator ignores transients up to 200µs at 100mV overdrive, ensuring robustness against power-rail noise.

It uses a single-supply architecture with no external components required, and its push-pull output drives low (≤0.3V at 1.6mA) when asserted and high (≥0.8·VCC) when deasserted-enabling direct interface with µP reset inputs without pull-up resistors.

Key Specifications

Pinout & Package

MAX6346UR46 is housed in a 3-pin SOT23-3 package (package code U3-1), with 1.3mm × 2.9mm footprint and 0.95mm height-compatible with high-density PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX809TR46D3T and TPS3808G33DBVR, the MAX6346UR46 provides tighter threshold accuracy (±2.5% vs ±3%), lower ICC (1µA vs 1.5–1.8µA), and guaranteed functionality down to 1.2V-making it optimal for space-constrained, battery-sensitive designs requiring precise 4.63V supervision without external components.

Availability

MAX6346UR46 is available at Aetrix Electronics and suitable for portable/battery-powered equipment, intelligent instruments, industrial controllers, critical µP power monitoring, and medical embedded systems requiring stable component supply and long-term manufacturability.

Supply support for MAX6346UR46 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 is a semiconductor company specializing in analog and mixed-signal ICs for power management, sensing, and interface applications.

The MAX63xx family was designed specifically for ultra-low-power microprocessor supervision in space- and energy-constrained systems-emphasizing precision threshold accuracy, minimal external components, and guaranteed operation across wide VCC and temperature ranges.

FAQ

What is the exact reset threshold voltage of MAX6346UR46 and how stable is it over temperature?

The MAX6346UR46 has a factory-trimmed nominal reset threshold of 4.63V, with tolerance of ±2.5% over the full operating temperature range of -40°C to +85°C. This stability is achieved through laser trimming and on-chip temperature compensation, and the device's reset threshold tempco is specified at 40ppm/°C-ensuring predictable, repeatable brownout detection in demanding environments where the MAX6346UR46 is deployed.

Does MAX6346UR46 require any external components to function?

No, the MAX6346UR46 requires no external components. Its internal precision voltage reference, comparator, and timing circuitry are fully integrated. The device operates with only VCC, GND, and RESET connections-eliminating the need for external resistors, capacitors, or trimming networks. This integration reduces BOM cost, PCB area, and design validation effort for applications using the MAX6346UR46.

What is the output configuration of MAX6346UR46 and how does it interface with a microprocessor?

The MAX6346UR46 features an active-low push-pull RESET output. When asserted, it actively pulls the RESET line low (≤0.3V at 1.6mA sink); when deasserted, it actively drives high (≥0.8·VCC at 500µA source). This eliminates the need for an external pull-up resistor and ensures strong, noise-immune signaling directly into standard µP reset inputs-making the MAX6346UR46 ideal for compact, high-reliability designs.

Can MAX6346UR46 operate reliably during deep brownout conditions?

Yes, the MAX6346UR46 is guaranteed to maintain correct reset state down to VCC = 1.2V over the full -40°C to +85°C temperature range. Its internal circuitry remains functional and the RESET output remains asserted until VCC recovers above 4.63V and sustains that level for ≥100ms. This capability makes the MAX6346UR46 suitable for applications where the power supply may dip severely before recovery-such as battery-powered systems with aging cells.

Is MAX6346UR46 pin-compatible with other supervisory ICs like MAX809 or MAX810?

Yes, the MAX6346UR46 is pin-compatible with the MAX809, MAX810, and related 3-pin SOT23 supervisory ICs-including identical pinout (VCC, RESET, GND) and footprint (U3-1). However, differences exist in reset threshold accuracy, supply current, and low-VCC operation: the MAX6346UR46 offers tighter 4.63V tolerance (±2.5%), lower 1µA ICC, and guaranteed 1.2V operation versus the MAX809's 1.5V minimum-so verify system-level requirements before substitution.