AD8138ARM

Overview

The AD8138ARM is a low distortion differential amplifier manufactured by Analog Devices Inc. in an 8-lead MSOP package. It features a -3 dB bandwidth of 320 MHz at G = +1 and a slew rate of 1150 V/µs. The device settles to 0.01% in 16 ns with an overdrive recovery time of 4 ns. Input offset voltage is typically 1 mV, and input bias current is 7 µA. Operating supply range spans from +3 V to ±5 V, consuming 90 mW at 5 V. Harmonic distortion reaches -94 dBc SFDR at 5 MHz and -85 dBc at 20 MHz.

Feature Summary

• Provides easy single-ended-to-differential conversion using proprietary XFCB bipolar process technology.
• Features unique internal feedback for balanced output gain and phase matching while suppressing even-order harmonics.
• Allows adjustable output common-mode voltage via the VOCM pin for level-shifting signals to drive single-supply ADCs.

Applications

• ADC drivers
• Single-ended-to-differential converters
• IF and baseband gain blocks
• Differential buffers
• Line drivers

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and temperature range. Confirm availability status through authorized distributors as supply conditions may vary. Ensure the component matches the required RoHS compliance standards for your assembly process.

Selection Notes

Select this component when high-speed differential signal processing is required with minimal harmonic distortion. The internal feedback architecture simplifies design by eliminating the need for tightly matched external resistors for balance. Consider the wide supply range and adjustable common-mode output for flexible interface requirements.

Part Context

The AD8138 represents an advancement over traditional op amps for differential applications. It eliminates the need for transformers in high-performance ADC interfaces, preserving low-frequency and DC information. The device is designed to drive state-of-the-art 10-bit to 16-bit converters at high frequencies effectively.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.

FAQ

How does the AD8138 achieve balanced differential outputs?

It uses a unique internal feedback feature that provides balanced output gain and phase matching, which suppresses even-order harmonics without requiring tightly matched external components.

What is the function of the VOCM pin?

The VOCM pin allows for adjustable output common-mode voltage, enabling easy level-shifting of input signals to drive single-supply ADCs.