JAJSHP9E November 2007 – July 2019 VCA824
PRODUCTION DATA.
The VCA824 functions as a differential input, single maximum gain of operation-ended output variable gain amplifier. This functional mode is enabled by applying power to the amplifier supply pins and is disabled by turning the power off. The gain is continuously variable through the analog gain control input. While the gain range is fixed, the maximum gain is set by two external components, Rf and Rg, as shown in the Functional Block Diagram. The maximum gain is equal to 2x (Rf / Rg). This gain is achieved with a 1-V voltage on the gain adjust pin VG. As the voltage decreases on the VG pin, the gain decreases in a linear in dB fashion with over 40 dB of gain range from 1-V to –1-V control voltage. As with most other differential input amplifiers, inputs can be applied to either one or both of the amplifier inputs. The amplifier gain is controlled through the gain control pin.