THAT 1240 Series Balanced Line Receiver ICs THAT Corporation THAT 1240 Series Balanced Line Receiver ICs are precision differential amplifiers that are designed primarily for audio applications. The THAT 1240 series include 1240, 1243, and 1246 variants. The THAT 1246 is drop-in compatible with the TI INA137 and Analog Devices SSM2143, and the THAT 1240 is pin-compatible with the INA134 and the SSM2141. These devices are laser trimmed in wafer form to obtain the precision resistor matching needed for high CMR performance and precise gain. The ICs are available in models which can be configured as differential amplifiers for 0dB, ±3dB, and ±6dB gain. The internal precision-trimmed thin-film resistors enable a wide variety of circuits that are virtually impossible to build with discrete components.