ISL22102 pdf datasheet (Amplif

The ISL22102 integrates two digitally controlled
potentiometers (DCP) with buffered wiper outputs and an
internal bias voltage generator (VB) on a monolithic CMOS
integrated circuit. The wiper position is adjusted by the user
through simple Up and Down push buttons, ideal for stereo
volume control in audio applications.
Each potentiometer is implemented using 31 polysilicon
resistors in a logarithmic array. Between each of the
resistors are tap points connected to the wiper terminal
through switches. When powered up, the wipers are reset to
the -20dB position.
In addition to the ISL22102’s low noise design, the ISL22102
also contains a zero-crossing detection circuitry to further
minimize click and pop noise during volume transition.
The internal VB generator of the ISL22102 provides a
precision middle scale voltage reference that reduces
external circuitry and simplifies application design.