Analog Devices Inc./Maxim Integrated MAX4337EKA+T

Overview

MAX4337EKA+T from Maxim Integrated is a dual rail-to-rail input/output operational amplifier in an 8-pin SOT23 package, delivering 50mA output drive per channel into 32Ω loads at 2.7V–5.5V single-supply operation. It features 5MHz gain-bandwidth, 90dB PSRR, shutdown mode (0.04μA per amplifier), and thermal overload protection-optimized for stereo headphone driver applications in portable audio systems.

For engineers reviewing the MAX4337EKA+T datasheet, MAX4337EKA+T pinout, MAX4337EKA+T application, or MAX4337EKA+T equivalent, key selection criteria include rail-to-rail I/O swing under 32Ω load, shutdown current <0.05μA, THD+N ≤0.003% at 10kHz/10kΩ, GBWP = 5MHz, and guaranteed operation from –40°C to +85°C.

Technical Context

The MAX4337EKA+T integrates two independent high-output-current op amps with complementary NPN/PNP rail-to-rail input stages enabling full common-mode range (GND to VCC) and no phase reversal on overdrive. Its output stage delivers ±50mA into 32Ω while maintaining <400mV headroom from rails at 5V supply.

Each amplifier includes dedicated SHDN control (pin 5 and pin 6 per channel), placing outputs in high-impedance state and reducing ICC to <0.04μA when pulled low. The device uses BiCMOS process, incorporates smart short-circuit protection (110mA limit), and remains stable with capacitive loads up to 200pF without external compensation.

Key Specifications

Pinout & Package

MAX4337EKA+T is housed in an 8-pin SOT23 package (package code K8+5, outline 21-0078), with exposed pad for thermal enhancement. Pin 1 is marked by dot; pin numbering follows standard SOT23 counterclockwise from notch/dot.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual rail-to-rail audio op amp applications.

Compared with MAX4410ETE+T and TLC072CDR, the MAX4337EKA+T uniquely combines dual-channel operation, per-channel shutdown, rail-to-rail I/O, and 32Ω drive capability in the ultra-small SOT23-8 package - making it the only option meeting all three requirements for space-constrained stereo headphone systems.

Availability

MAX4337EKA+T is available at Aetrix Electronics and suitable for portable audio systems, battery-powered instrumentation, and automotive hands-free interfaces requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX4337EKA+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 precision analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX4335–MAX4338 family was designed specifically for high-fidelity, low-voltage audio signal conditioning - targeting portable headphone drivers, DAC/ADC buffers, and transformerless line drivers where rail-to-rail swing and low distortion are critical.

FAQ

What is the maximum output current capability of the MAX4337EKA+T?

The MAX4337EKA+T delivers ±50mA per channel into 32Ω loads at both 2.7V and 5.5V supply voltages, with output voltage swing maintained within 400mV of the rails. This is verified across –40°C to +85°C and enables direct drive of stereo headphones without external transistors. Short-circuit protection limits current to 110mA during fault conditions.

Does the MAX4337EKA+T support true rail-to-rail input and output operation?

Yes, the MAX4337EKA+T features rail-to-rail input (common-mode range from GND to VCC) and rail-to-rail output (swing within 100mV of rails with 10kΩ load, 400mV with 32Ω). Its dual-input-stage architecture - combining NPN and PNP differential pairs - ensures continuous operation across the full supply range without phase reversal or dead zones.

How does the shutdown function work on the MAX4337EKA+T?

The MAX4337EKA+T has two independent shutdown pins (SHDN1 on pin 5, SHDN2 on pin 6). Pulling either pin low disables its respective amplifier, reducing supply current to <0.04μA and placing the output in high-impedance state. Both pins must be high (or tied to VCC) for normal operation. Enable/disable timing is <1μs, and power-up settling is <5μs.

What is the typical THD+N performance of the MAX4337EKA+T at audio frequencies?

The MAX4337EKA+T achieves 0.003% THD+N at 10kHz with 5V supply and 10kΩ load, and 0.01% at 10kHz into 32Ω at 2.7V. These values are measured with 2V_P-P output and a 500kHz low-pass filter. Performance remains stable across temperature and supply voltage, supporting high-fidelity portable audio applications.

Can the MAX4337EKA+T drive capacitive loads without oscillation?

Yes, the MAX4337EKA+T is internally compensated for stability with capacitive loads up to 200pF across all operating conditions. It remains stable driving typical cable capacitances and ADC input filters without requiring external isolation resistors. For loads exceeding 200pF, adding a 10–39Ω series resistor at the output restores phase margin.