Texas Instruments VCA8500
The VCA8500 is an 8-channel variable gain amplifier consisting of a low-noise pre-amplifier (LNP) and a variable-gain amplifier (VGA). This combination, along with the device features, makes it ideal for a variety of ultrasound systems. The LNP gain is fixed at 20dB, and has excellent noise and signal handling characteristics.| Part No. | VCA8500 |
|---|---|
| Datasheet | VCA8500 Download |
| Manufacturer |  Texas Instruments |
| Description | Variable Gain Amplifier |
| Buy | Stock & Price |
FEATURES
1●2345 Ultralow Power: 65mW/Channel
● Low Noise: 0.8nV/√Hz
● Low-Noise Pre-Amp (LNP): – 20dB Fixed Gain – 250mVPP Linear Input Range
● Variable Gain Amplifier: – Gain Control Range: 46dB – Selectable PGA Gain: 20dB, 25dB, 27dB, 30dB – Fast Overload Recovery – Output Clamping Control
● Integrated Low-Pass Filter: – Second-Order, Linear Phase – Bandwidth: 10MHz, 15MHz
● High Accuracy: – Low Gain Error: ±0.5dB – Excellent Channel Matching: ±0.25dB
● Distortion, HD2: –50dBc at 5MHz
● Integrated CW Switch Matrix: – Easy Current Summing
● Serial Control Interface
● Small Package: QFN-64, 9×9mm
APPLICATIONS
● Medical Imaging, Ultrasound Systems – Portable Systems – Low- and Mid-Range SystemsDESCRIPTION
The gain of the voltage-controlled attenuator can vary over a 46dB range with a 0V to 1.2V control voltage common to all channels of the VCA8500. The post-gain amplifier (PGA) can be programmed for four gain settings: 20dB, 25dB, 27dB, or 30dB gain. As a means to improve system overload recovery time, the VCA8500 provides an internal clamping function.
