The VCA5807 is an integrated Voltage Controlled Amplifier (VCA) specifically designed for ultrasound systems in which high performance and small size are required. The VCA5807 integrates a complete time-gain-control (TGC) imaging path and a continuous wave Doppler (CWD) path. It also enables users to select one of various power/noise combinations to optimize system performance. Therefore, the VCA5807 is a suitable ultrasound analog front end solution not only for high-end systems, but also for portable systems.

The VCA5807 contains eight channels of voltage controlled amplifier (VCA), and CW mixer. The VCA includes Low noise Amplifier(LNA), Voltage controlled Attenuator (VCAT), Programmable Gain Amplifier (PGA), and Low-Pass Filter (LPF). The LNA gain is programmable to support 250 mVPPto 1 VPPinput signals. Programmable active termination is also supported by the LNA. The ultra-low noise VCAT provides an attenuation control range of 40dB and improves overall low gain SNR which benefits harmonic imaging and near field imaging. The PGA provides gain options of 24 dB and 30 dB. Before the ADC, a LPF can be configured as 10 MHz, 15 MHz, 20 MHz, or 30 MHz to support ultrasound applications with different frequencies. In addition, the signal chain of the VCA5807 can handle signal frequency lower than 100 KHz, which enables it to be used not only in ultrasound applications but also in sonar applications.

The VCA5807 integrates a low power passive mixer and a low noise summing amplifier to accomplish on-chip CWD beamformer. 16 selectable phase-delays can be applied to each analog input signal. Meanwhile a unique 3rdand 5thorder harmonic suppression filter is implemented to enhance CW sensitivity.Read more