Analog Devices Inc./Maxim Integrated MAX4245AXT

Overview

The MAX4245AXT from Maxim Integrated is a single-channel, rail-to-rail input/output operational amplifier with shutdown control, housed in a 6-pin SC70 package. It operates from +2.5V to +5.5V, draws 320µA quiescent current per amplifier, delivers 1MHz gain-bandwidth, and supports capacitive loads up to 470pF - ideal for battery-powered sensor-signal detection and portable communications systems.

For engineers reviewing the MAX4245AXT datasheet, MAX4245AXT pinout, MAX4245AXT application, or MAX4245AXT equivalent, key selection criteria include its 50nA shutdown current, ±0.4mV input offset voltage (typ), rail-to-rail swing within 35mV of rails at 2kΩ load, -40°C to +125°C operation, and SC70 footprint compatibility for space-constrained designs.

Technical Context

The MAX4245AXT uses a composite NPN/PNP input stage enabling true rail-to-rail common-mode range (VSS − 0.1V to VDD + 0.1V) and no phase inversion on overdriven inputs. Its output stage delivers rail-to-rail swing with 110dB open-loop gain into 2kΩ and maintains unity-gain stability with up to 470pF capacitive load.

Shutdown is controlled by an active-low SHDN pin referenced to VSS, reducing supply current to 50nA (max) and placing the output in high-impedance state. The device features 70° phase margin, 20dB gain margin, and 0.4V/µs slew rate - optimized for low-noise, low-power precision amplification in single-supply systems.

Key Specifications

Pinout & Package

The MAX4245AXT is packaged in a 6-pin SC70 (2.0mm × 1.25mm, 0.65mm pitch), optimized for ultra-dense PCB layouts. Pin 1 is IN+, Pin 2 is VSS, Pin 3 is IN−, Pin 4 is OUT, Pin 5 is SHDN, and Pin 6 is VDD - fully compatible with standard SC70 land patterns (Maxim land pattern #90-0189).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar op amp applications.

Compared with MAX4245AXT, MAX4475AUT offers lower active current but forfeits shutdown functionality, while TLV9001IDBVR trades industrial temperature qualification and robust capacitive-load stability for broader distribution and lower unit cost - making MAX4245AXT the optimal choice for harsh-environment, battery-gated systems demanding guaranteed performance across all parameters.

Availability

MAX4245AXT is available at Aetrix Electronics and suitable for portable communications, sensor-signal detection, and infrared receiver designs requiring stable component supply across automotive (-40°C to +125°C) and industrial temperature ranges.

Supply support for MAX4245AXT 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 demanding industrial, automotive, and communications applications.

The MAX4245AXT belongs to Maxim's ultra-low-power, rail-to-rail op amp family engineered specifically for battery-operated instrumentation and sensor interfaces where supply headroom, quiescent current, and output swing are critical constraints.

FAQ

What is the maximum capacitive load the MAX4245AXT can drive while remaining unity-gain stable?

The MAX4245AXT is guaranteed unity-gain stable with capacitive loads up to 470pF, as confirmed in the Electrical Characteristics table and Typical Operating Characteristics (Figure 15/16). This eliminates the need for external isolation resistors in most RC filter, ADC driver, and cable interface applications - unlike many general-purpose op amps that require compensation beyond 100pF.

Does the MAX4245AXT support dual-supply operation, and what are the voltage limits?

Yes, the MAX4245AXT supports dual-supply operation from ±1.25V to ±2.75V, derived from its single-supply range of +2.5V to +5.5V. When using dual supplies, VDD connects to the positive rail and VSS to the negative rail; SHDN must be referenced to VSS (not ground) to ensure correct shutdown behavior, as specified in the Applications Information section.

What is the input common-mode voltage range for the MAX4245AXT, and how does it affect sensor interfacing?

The MAX4245AXT features a rail-to-rail input stage with a common-mode range of VSS − 0.1V to VDD + 0.1V at +25°C (extended to VSS to VDD over full temperature range). This allows direct interfacing with sensors whose output spans near the supply rails - such as bridge-based pressure transducers or current-sense amplifiers - without level-shifting circuitry.

How does the shutdown function of the MAX4245AXT behave, and what design precautions are required?

The MAX4245AXT enters shutdown when the SHDN pin is pulled low (≤0.3×VDD), reducing supply current to 50nA (max) and placing the output in high-impedance state. Critical precautions include avoiding floating SHDN - it must be actively driven to VSS (not left open) due to internal pullup current, and must reference VSS (not GND) in dual-supply configurations to prevent indeterminate logic states.

What is the typical input offset voltage drift over temperature for the MAX4245AXT, and how does it impact precision DC measurements?

The MAX4245AXT exhibits ±2µV/°C input offset voltage drift (TCV_OS) over the full -40°C to +125°C range, as specified in the Electrical Characteristics table. This low drift ensures minimal calibration drift in precision DC applications - for example, adding only ±0.24mV error over a 120°C span - making it suitable for high-accuracy sensor front-ends without frequent recalibration.