Analog Devices Inc./Maxim Integrated MAX6833FXRD3+

Overview

MAX6833FXRD3+ from Maxim Integrated is a push-pull active-high voltage supervisor IC designed for ultra-low-voltage microprocessor reset monitoring in 1.2V–1.8V digital systems. It features a factory-set 1.050V reset threshold (±2.5% over temperature), 210ms reset timeout period, and 7.5µA typical supply current - enabling reliable power-on reset assertion in portable battery-powered equipment.

For engineers reviewing the MAX6833FXRD3+ datasheet, MAX6833FXRD3+ pinout, MAX6833FXRD3+ application, or MAX6833FXRD3+ equivalent, key selection criteria include its SC70-3 package, guaranteed reset validity down to VCC = 0.75V, immunity to short negative VCC transients, and compatibility with manual reset input requirements in space-constrained embedded designs.

Technical Context

The MAX6833FXRD3+ implements a precision bandgap-based voltage comparator with hysteresis (0.75% of VTH) to monitor VCC against a fixed 1.050V threshold. Its internal timing circuit generates a precise 210ms reset-active timeout after VCC rises above threshold or MR deassertion.

This device uses a push-pull output stage capable of sourcing 50µA at 0.8×VCC when asserted (RESET = HIGH), and sinking 80µA at 0.2×VCC when deasserted (RESET = LOW), ensuring robust interface with µP reset inputs across its full operating range of –40°C to +85°C.

Key Specifications

Pinout & Package

MAX6833FXRD3+ is housed in a 3-pin SC70-3 package (1.25mm × 0.85mm, 0.65mm pitch) with gull-wing leads. The package is RoHS-compliant and rated for –40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage supervisor applications.

Compared with MAX6832FXRD3+, the MAX6833FXRD3+ provides native active-high reset signaling - eliminating level-shifting components and reducing layout complexity. Against TLV803EB29DBZR, it delivers tighter threshold accuracy (±2.5% vs ±3.5%) and guaranteed operation down to 0.75V VCC - critical for deep-brownout resilience in 1.2V SoC designs.

Availability

MAX6833FXRD3+ is available at Aetrix Electronics and suitable for portable electronics, industrial sensor nodes, and USB-C power delivery adapters requiring stable component supply with long-term lifecycle support.

Supply support for MAX6833FXRD3+ 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 - acquired by Analog Devices in 2021.

The MAX6832–MAX6840 family was engineered specifically for ultra-low-voltage microprocessor reset supervision in battery-constrained systems, emphasizing minimal quiescent current, small footprint, and high noise immunity.

FAQ

What is the exact reset threshold voltage of the MAX6833FXRD3+ and how stable is it over temperature?

The MAX6833FXRD3+ has a factory-set reset threshold of 1.050V with ±2.5% accuracy over the full –40°C to +85°C operating range. This specification is guaranteed by design and 100% production tested at +25°C. The normalized threshold variation versus temperature is less than ±0.5% across the range, as confirmed in the Typical Operating Characteristics plot (toc04).

Does the MAX6833FXRD3+ require an external pullup resistor on its RESET pin?

No, the MAX6833FXRD3+ features a push-pull active-high RESET output and does not require an external pullup resistor. Its output actively drives HIGH during reset assertion and LOW during deassertion. A 100kΩ pullup to VCC is recommended only if RESET signal validity must be maintained below 0.85V VCC - but this is not required for standard operation.

Can the MAX6833FXRD3+ monitor supply voltages below 1.050V?

No - the MAX6833FXRD3+ is a fixed-threshold device with a nominal 1.050V trip point. To monitor voltages below 1.050V (e.g., 0.6V or 0.8V), you must select a variant from the MAX6838–MAX6840 series with RESET-IN capability, such as MAX6839XSD3+, which uses an external resistor divider to set thresholds down to 0.44V.

What is the minimum VCC voltage at which the MAX6833FXRD3+ guarantees valid reset output behavior?

The MAX6833FXRD3+ guarantees valid active-high RESET output down to VCC = 0.75V. Below this voltage, reset assertion is no longer assured. This is explicitly specified in the Electrical Characteristics table under "Guaranteed Reset Valid to VCC" for active-high variants, and distinguishes it from active-low versions that operate down to 0.55V.

Is the MAX6833FXRD3+ pin-compatible with older Maxim reset ICs like the MAX809?

Yes - the MAX6833FXRD3+ is pin-compatible with the MAX809 series in SC70-3 package. Both share identical pinout (GND, RESET, VCC) and similar functional behavior, though MAX6833FXRD3+ offers improved threshold accuracy (±2.5% vs ±3.5%), lower quiescent current (7.5µA vs 12µA), and enhanced transient immunity per the datasheet compatibility statement.