70-MHz Programmable-Gain Amplifiers

The THS7001 (single) and THS7002 (dual) are high-speed programmable-gain Amplifiers ideal for applications where load impedance CAN often vary. Each channel on this device consists of a separate low-noise input preamp and a Programmable Gain Amplifier (PGA). The preamp is a voltage-feedback Amplifier offering a low 1.7-nV/Hz voltage noise with a 100-MHz (-3 dB) bandwidth. The output pin of the preamp is accessible so that Filters CAN be easily added to the Amplifier The 3-bit digitally-controlled PGA provides a -22-dB to 20-dB attenuation/gain range with a 6-dB step resolution. In addition, the PGA provides both high and low output clamp protection to prevent the output signal from swinging outside the common-mode input range of an Analog-to-digital converter. The PGA provides a wide 70-MHz (-3 dB) bandwidth, which remains relatively constant over the entire gain/attenuation range. Independent shutdown control is also provided for power conservation and multiplexing. These devices operate over a wide 4.5-V to 16-V supply voltage range. By Texas Instruments