Volume control board kit  


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  This kit is a stereo volume control (attenuator) based on the Burr-Brown chip PGA2310. The chip is a 256-step attenuator and output buffer. The "gain" can be adjusted from -95.5 to +31.5dB in 0.5dB steps. As the chip includes a buffer stage with gain, the chip can replace a normal linestage.

In this application I have chosen 1dB steps (0.5dB is not very much). The range is either -95 to 0dB or -95 to +31dB depending on the setup.

The PGA2310 has to be driven from a low impedance source (less than 600R). As not all sources are that low, I have added an input buffer stage based on the Burr-Brown OPA2134 audio op. amp. This also increases the input impedance of the attenuator from 10k to 100k, which may be helpful in some situations. If the input buffer is not needed, it can be bypassed. The board also includes a power supply for the audio section. This section runs on 12-15V AC. The digital section needs +5V, which can be supplied by an input selector board.

This kit can be used with any of the control boards, or you can design your own according to the specifications in the datasheet. The board size is 65*59mm.

PGA2310 datasheet (PDF 320kB)
ChipVol1 schematic (GIF 38kB)

Qty: Order code: Description: Price (ex. VAT):
ChipVol1 Volume control board 40,00 €
ChipVol1NB Volume control board (no buffer) 37,00 €
ChipVol1PCB Volume control board - PCB only 8,00 €
Delivery time: 3-4 days