Description

The AD8138 is a major advancement over op amps fordifferential signal processing. The AD8138 can be used as asingle-ended-to-differential amplifier or as a differential-to-differentialamplifier. The AD8138 is as easy to use as an opamp and greatly simplifies differential signal amplification anddriving. Manufactured on the proprietary ADI XFCB bipolarprocess, the AD8138 has a −3 dB bandwidth of 320 MHz anddelivers a differential signal with the lowest harmonic distortionavailable in a differential amplifier. The AD8138 has a uniqueinternal feedback feature that provides balanced output gainand phase matching, suppressing even order harmonics. Theinternal feedback circuit also minimizes any gain error thatwould be associated with the mismatches in the external gainsetting resistors.The differential output of the AD8138 helps balance the inputto differential ADCs, maximizing the performance of the ADC. The AD8138 eliminates the need for a transformer with highperformance ADCs, preserving the low frequency and dc information.The common-mode level of the differential output isadjustable by a voltage on the VOCM pin, easily level-shifting theinput signals for driving single-supply ADCs. Fast overloadrecovery preserves sampling accuracy. The AD8138 distortion performance makes it an ideal ADCdriver for communication systems, with distortion performancegood enough to drive state-of-the-art 10-bit to 16-bit convertersat high frequencies. The high bandwidth and IP3 of theAD8138 also make it appropriate for use as a gain block in IFand baseband signal chains. The AD8138 offset and dynamicperformance makes it well suited for a wide variety of signalprocessing and data acquisition applications. The AD8138 is available in both SOIC and MSOP packages foroperation over −40°C to +85°C temperatures.The AD8138-EP supports defense and aerospace applications (AQEC).