A 0.58mW dB-Linear Time Gain Compensation Amplifier with ±0.5-dB Gain Error for Imaging Applications

This paper presents a low-power time gain compensation (TGC) amplifier that provides accurate dB-linear voltage gain for imaging applications. Different from the conventional amplifier, the TGC amplifier generates exponentially variable gain over time to compensate the increasing signal attenuation along the ultrasound propagation path. This TGC amplifier employs a current-steering architecture to control the bias currents for the core cells. Implemented in a 55nm CMOS BCDLITE process, this design occupies an active chip area of 0.11mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and consumes a total power of 0.58mW. Compared to the state-of-the-art TGC designs, the proposed TGC amplifier demonstrated the capability to maintain a dB-linear gain up to 14dB with less than ±0.5 dB gain error. This circuit is well-suited for integration with other high-voltage (HV) blocks, enabling a monolithic transceiver implementation.