The Digital volume control circuit has been designed to work with external wired remote has 16 levels of volume-driven volume up button and reset button. DD1 - counter displays 16-bit binary code to control the T shaped voltage divider. DD2 is used as a clock. DD3 inverts the signal from the counter. The regulatory element is made on resistors R6/R7, R8/R9 and transistor switches that are connected certain resistance to ground formed a T shaped voltage divider.
Circuit note :
1 - turn up the volume
2 - reset
3 - Clock output
Digital volume control Parts list :
R1..R5 1K
R6..R9 22K
R10 - R14 3.9K
R11 - R15 2.2K
R12 - R16 1K VT КТ3102
R13 - R17 510
R18..25 22K
C1 10mkF*16V
C2 47mkF*16V
C3,C4 100mkF*16V
DD1 К555ИЕ7
DD2,DD3 К555ЛН1
DA1 КР142ЕН5А
