Analog Devices Inc./Maxim Integrated MAX4481AXT+T

Overview

MAX4481AXT+T from Maxim Integrated is a single-channel, rail-to-rail output operational amplifier with active-low shutdown control, operating from +2.5V to +5.5V, drawing 50μA quiescent current (typ), sinking/source 3mA load current, and specified for -40°C to +125°C automotive temperature range in a 6-pin SC70 package. It serves as a low-power signal conditioning amplifier in portable sensor interfaces and zero-crossing detectors.

For engineers reviewing the MAX4481AXT+T datasheet, MAX4481AXT+T pinout, MAX4481AXT+T application, or MAX4481AXT+T equivalent, key selection criteria include shutdown current (<0.5μA), rail-to-rail output swing (within 80mV of rails at 5kΩ), unity-gain stability up to 400pF capacitive load, input offset voltage (±5.5mV max), and THD (0.005% at 100kΩ).

Technical Context

The MAX4481AXT+T employs a BiCMOS input stage enabling ultra-low input bias current (±100pA max) and high input resistance (1000MΩ), paired with a rail-to-rail CMOS output stage delivering 3mA sink/source capability. Its internal architecture supports stable operation with capacitive loads up to 400pF without external compensation.

Shutdown functionality is implemented via an active-low SHDN pin that reduces supply current to ≤0.5μA and places the output in high-impedance state; enable delay is 12μs and shutdown delay is 0.4μs. The device achieves 105dB open-loop gain with 5kΩ load and maintains >71dB common-mode rejection across its full operating voltage range.

Key Specifications

Pinout & Package

MAX4481AXT+T is housed in a 6-pin SC70 package (package code X6SN+1, outline 21-0077), measuring 2.0mm × 1.25mm × 0.9mm, with exposed pad not electrically connected. This RoHS-compliant, surface-mount package supports high-density PCB layouts in space-constrained portable electronics.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar single-channel, low-power, rail-to-rail op amp applications.

Compared with TLV8511IDBVR and OPA316IDBVR, the MAX4481AXT+T uniquely balances sub-1μA shutdown, 140kHz bandwidth, rail-to-rail output, and automotive-grade temperature range in a 6-pin SC70-making it optimal for battery-powered, temperature-resilient sensor nodes requiring controlled power cycling.

Availability

MAX4481AXT+T is available at Aetrix Electronics and suitable for portable communications, electronic ignition modules, and infrared receiver designs requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX4481AXT+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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The MAX4480–MAX4483 family was designed for cost-sensitive, low-power, single-supply signal conditioning in harsh environments-emphasizing rail-to-rail output, shutdown capability, and extended temperature operation.

FAQ

What is the maximum capacitive load the MAX4481AXT+T can drive while remaining unity-gain stable?

The MAX4481AXT+T is unity-gain stable with capacitive loads up to 400pF, as confirmed in the Electrical Characteristics table and Typical Operating Characteristics (Figure MAX4480 toc19). This allows direct connection to ADC input capacitors or long PCB traces without external isolation resistors. Exceeding 400pF may cause peaking or oscillation; for larger loads, a series resistor (e.g., 10–100Ω) between OUT and C_L restores stability. The MAX4481AXT+T's internal compensation is optimized for this limit across the full −40°C to +125°C range.

Does the MAX4481AXT+T require external bypass capacitors, and if so, what value and placement is recommended?

Yes, the MAX4481AXT+T requires a 0.1μF ceramic bypass capacitor placed as close as possible between VDD and VSS pins, per the Applications Information section. This minimizes power supply noise coupling into the amplifier's sensitive input stage and prevents instability. A second 0.01μF capacitor is recommended for high-frequency decoupling if layout constraints permit. Avoid shared vias or long traces-capacitor pads must connect directly to the SC70 package's VDD and VSS lands. The MAX4481AXT+T's low 50μA quiescent current makes it especially susceptible to supply ripple, so proper decoupling is essential for THD and PSRR performance.

What is the typical enable time and shutdown delay for the MAX4481AXT+T, and how do these affect system power sequencing?

The MAX4481AXT+T has a typical enable delay (t_EN) of 12μs and shutdown delay (t_SHDN) of 0.4μs, measured from SHDN logic transition to output settling. These values allow rapid power cycling in duty-cycled sensor systems-e.g., waking every 100ms for 1ms measurement windows. Because t_SHDN is significantly shorter than t_EN, the device exits shutdown faster than it enters it, simplifying timing margins. During enable, the output settles within 50μs (power-on time), ensuring clean signal acquisition. These delays are characterized over −40°C to +125°C and apply directly to the MAX4481AXT+T in its 6-pin SC70 package.

Can the MAX4481AXT+T operate from a 2.5V supply, and what performance parameters degrade at minimum VDD?

Yes, the MAX4481AXT+T is fully specified from +2.5V to +5.5V. At VDD = 2.5V, quiescent current drops to 45μA (typ), output swing remains rail-to-rail (within ~100mV of rails at 5kΩ), and THD stays at 0.005%. However, large-signal voltage gain decreases from 105dB (at 5V) to 94dB, and PSRR degrades from 92dB to 82dB. Input common-mode range shrinks to VSS to VDD − 1.3V, limiting usable input headroom. These trade-offs are documented in the Electrical Characteristics table and are consistent across the MAX4481AXT+T's temperature range.

Is the MAX4481AXT+T pin-compatible with other devices in the MAX4480–MAX4483 family, and what are the physical package differences?

No, the MAX4481AXT+T is not pin-compatible with other family members. It uses a 6-pin SC70 package (pin 6 = SHDN), whereas MAX4480AXK+T uses a 5-pin SC70 (no SHDN) and MAX4482AKA+T uses an 8-pin SOT23. Pinouts differ fundamentally: MAX4481AXT+T assigns IN+, IN−, OUT, VDD, VSS, SHDN to pins 1–6 respectively; MAX4480 omits SHDN and repurposes pin 6 as NC. Mechanical dimensions also differ-SC70-6 (2.0mm × 1.25mm) vs. SC70-5 (1.6mm × 1.25mm)-so PCB footprints are not interchangeable. The MAX4481AXT+T's unique 6-pin configuration is required to accommodate shutdown control.