Analog Devices Inc./Maxim Integrated MAX6834FXRD3+T

Overview

MAX6834FXRD3+T from Maxim Integrated is an ultra-low-voltage, open-drain active-low microprocessor reset circuit in SC70-3 package, designed to monitor +1.05V supply rails with ±2.5% threshold accuracy over -40°C to +85°C. It asserts reset when VCC falls below 1.05V and maintains active reset for 210ms after recovery, supporting brownout protection in portable battery-powered systems.

For engineers reviewing the MAX6834FXRD3+T datasheet, MAX6834FXRD3+T pinout, MAX6834FXRD3+T application, or MAX6834FXRD3+T equivalent, key selection criteria include its 1.05V factory-set threshold, 210ms timeout, 7.5µA typical supply current, open-drain RESET output requiring external pullup, and guaranteed operation down to VCC = 0.55V.

Technical Context

The MAX6834FXRD3+T implements a precision voltage comparator with 444mV internal reference, comparing VCC directly against a factory-trimmed threshold (1.05V). Its reset assertion logic is synchronized to VCC transitions with built-in hysteresis (0.75% of VTH) to reject fast transients.

This device uses BiCMOS process technology (681 transistors), features no manual reset (MR) or RESET-IN pins, and delivers fixed 210ms reset timeout (D3 suffix) without external timing components. The open-drain output allows level-shifting and bidirectional reset interfacing with µPs.

Key Specifications

Pinout & Package

MAX6834FXRD3+T is housed in a 3-pin SC70-3 package (1.25mm × 0.85mm, 0.65mm pitch), with GND on pin 1, RESET (open-drain active-low) on pin 2, and VCC on pin 3.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage detector and µP reset applications.

Compared with MAX6834FXRD3+T, MAX6381XR22+T eliminates the pullup requirement but forfeits level-shifting capability, while TPS3123E10DBVR reduces current draw by 80% but trades off threshold accuracy and transient rejection-making MAX6834FXRD3+T optimal for robust, multi-rail reset coordination in compact industrial wearables.

Availability

MAX6834FXRD3+T is available at Aetrix Electronics and suitable for portable medical diagnostics, industrial sensor nodes, wearable health monitors, and low-power IoT edge devices requiring stable component supply with guaranteed long-term availability.

Supply support for MAX6834FXRD3+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 is a semiconductor company specializing in analog and mixed-signal ICs for power, sensing, interface, and reliability-critical applications.

The MAX6832–MAX6840 family was designed specifically for ultra-low-voltage microprocessor supervision in battery-constrained systems, emphasizing minimal footprint, sub-10µA current, and precise factory-trimmed thresholds from 1.05V to 1.665V.

FAQ

What is the exact reset threshold voltage and accuracy of MAX6834FXRD3+T?

The MAX6834FXRD3+T has a factory-set reset threshold of 1.05V with ±2.5% accuracy over the full operating temperature range (-40°C to +85°C), as specified in the Electrical Characteristics table under "Reset Threshold (VTH)" for suffix F. This value is trimmed during production and does not require external calibration.

Does MAX6834FXRD3+T include a manual reset (MR) input?

No, the MAX6834FXRD3+T does not include a manual reset (MR) input. It is a dedicated voltage-monitoring reset circuit with only three pins: VCC, GND, and open-drain RESET. MR functionality is present only in the MAX6835/MAX6836/MAX6837 variants (SC70-4 packages).

What is the required external pullup resistor value for the open-drain RESET output of MAX6834FXRD3+T?

The MAX6834FXRD3+T RESET output requires an external pullup resistor to a defined logic-high voltage (e.g., 1.8V, 3.3V, or 5V). Typical values range from 10kΩ to 100kΩ; 47kΩ is commonly used to balance speed, power, and noise immunity. The datasheet specifies VOL ≤ 0.2V at ISINK = 200µA when VCC ≥ 1.5V.

Can MAX6834FXRD3+T operate reliably when VCC drops below 1.0V?

Yes, the MAX6834FXRD3+T guarantees valid reset assertion down to VCC = 0.55V (active-low), as confirmed in the Absolute Maximum Ratings and Electrical Characteristics tables. Below 0.55V, the output becomes high-impedance, but the 0.55V lower limit ensures robust brownout detection during deep battery discharge.

Is MAX6834FXRD3+T pin-compatible with other devices in the MAX6832–MAX6840 family?

The MAX6834FXRD3+T shares the same SC70-3 pinout (GND, RESET, VCC) with MAX6832 and MAX6833 variants, but differs functionally: MAX6832 uses push-pull active-low RESET, MAX6833 uses push-pull active-high RESET, while MAX6834FXRD3+T uses open-drain active-low RESET. Pin compatibility exists physically, but electrical interface requirements differ.