THS4561 Fully Differential Amplifier (FDA) Texas Instruments THS4561 Fully Differential Amplifier (FDA) offers a simple interface from single-ended sources to the differential output required by precision analog-to-digital converters (ADCs). THS4561 is designed for a very low, 8Hz, 1/f voltage noise corner and low, 130dB total harmonic distortion (THD) while consuming on a 775µA quiescent current. The THS4561 is well suited for power-sensitive data acquisition (DAQ) systems where high performance is required with the best signal-to-noise ratio (SNR) and spurious-free dynamic range (SFDR) through the amplifier and ADC combination.