Analog Devices Inc./Maxim Integrated MAX6803US46D3+T

Overview

The MAX6803US46D3+T from Maxim Integrated is a push/pull, active-high microprocessor supervisory circuit designed for precise 4.63V power-supply monitoring in embedded systems. It asserts RESET when VCC falls below 4.63V (±3% over temperature) or upon manual reset, with a guaranteed 100ms minimum timeout and valid operation down to 0.7V supply voltage. Used in critical µP power monitoring for industrial controllers and portable equipment.

For engineers reviewing the MAX6803US46D3+T datasheet, MAX6803US46D3+T pinout, MAX6803US46D3+T application, or MAX6803US46D3+T equivalent, key selection criteria include its factory-trimmed 4.63V threshold, 100ms reset timeout, active-high push/pull output, ultra-low 4µA supply current, and guaranteed reset validity to VCC = 0.7V across –40°C to +125°C.

Technical Context

The MAX6803US46D3+T implements a precision bandgap-based reset comparator with factory-trimmed 4.63V threshold (±1.8% at +25°C, ±3% over full temperature range) and built-in immunity to fast VCC transients (<30µs propagation delay). Its internal 20kΩ MR pullup enables direct connection of a momentary switch to GND without external debounce circuitry.

This device uses BiCMOS process technology and features a push/pull RESET output capable of sourcing ≥800µA at VCC ≥4.25V while maintaining VOH ≥0.8×VCC, and sinking up to 3.2mA with VOL ≤0.4V - enabling direct interface with high-impedance µP reset inputs without external pullup resistors.

Key Specifications

Pinout & Package

MAX6803US46D3+T is housed in a lead-free 4-pin SOT143 package (U4-1 outline, 21-0052 land pattern), optimized for space-constrained PCB layouts with 1.3mm × 1.3mm footprint and 0.95mm height.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6803US46D3+T, MAX6314US46D3+T sacrifices extended temperature range and adds 100% higher supply current, while TPS3808G33DBVR offers lower ICC but cannot replace 4.63V monitoring or provide manual reset - making MAX6803US46D3+T uniquely suited for 5V industrial brownout protection with full feature set.

Availability

MAX6803US46D3+T is available at Aetrix Electronics and suitable for industrial PLCs, portable medical devices, automotive body control modules, and smart energy meters requiring stable component supply with guaranteed long-term availability.

Supply support for MAX6803US46D3+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 and mixed-signal ICs for industrial, automotive, and computing applications with emphasis on reliability and integration.

The MAX6803 series targets space-constrained µP supervision in harsh environments, delivering factory-trimmed thresholds, ultra-low power, and guaranteed operation down to 0.7V - specifically engineered for fail-safe reset in mission-critical embedded systems.

FAQ

What is the exact reset threshold voltage of the MAX6803US46D3+T and how does it vary with temperature?

The MAX6803US46D3+T has a factory-trimmed nominal reset threshold of 4.63V at +25°C, with tolerance of ±1.8% at room temperature and ±3% over the full –40°C to +125°C operating range. This specification is confirmed in Table 1 of the datasheet and ensures consistent brownout detection across industrial temperature extremes without external calibration.

Does the MAX6803US46D3+T require an external pullup resistor on its RESET pin?

No, the MAX6803US46D3+T does not require an external pullup resistor because it features a push/pull active-high RESET output capable of sourcing ≥800µA at VCC ≥4.25V while maintaining VOH ≥0.8×VCC. This allows direct connection to high-impedance µP reset inputs without additional components - a key design advantage over open-drain alternatives like the MAX6805.

What is the minimum supply voltage at which the MAX6803US46D3+T guarantees correct reset behavior?

The MAX6803US46D3+T guarantees correct reset assertion and deassertion down to VCC = 0.7V across the full –40°C to +125°C temperature range. This is explicitly stated in the Electrical Characteristics table and enables reliable operation during deep brownout conditions where other supervisors may fail to hold reset.

How is the 100ms reset timeout period implemented in the MAX6803US46D3+T?

The MAX6803US46D3+T implements a factory-programmed 100ms minimum reset timeout period using on-chip RC timing with temperature compensation. The datasheet specifies tRP = 100ms (min), 150ms (typ), and 200ms (max) at +25°C, with normalized variation of ±15% over –40°C to +125°C - ensuring robust µP initialization timing across environmental conditions.

Can the MAX6803US46D3+T be used with microcontrollers that have bidirectional reset pins?

Yes, the MAX6803US46D3+T can interface with µPs having bidirectional reset pins through appropriate level-shifting or open-drain emulation. While its push/pull output differs from the open-drain MAX6805, adding a series resistor (e.g., 100Ω) and external pullup enables safe bidirectional operation - as validated in Maxim Application Note 5372 for Motorola 68HC11 compatibility.