DS1801

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OPERATION

The DS1801 provides two 65-position potentiometers per package, each having a logarithmic resistive

characteristic as shown in Table 1. The DS1801 is controlled by a 3-wire serial interface. The 3-wire

serial interface is designed for CPU-controlled applications and allows the potentiometer’s exact wiper

position to be read or written.

The DS1801 design supports daisy-chaining for multi-device

environments.

Figure 1 presents a block diagram of the DS1801. As shown, the inputs from the 3-wire serial interface

drive a command/control unit. The command/control unit interprets these inputs for control of the two

potentiometers.

On power-up, the serial port is stable and active within 10 microseconds. The wiper position on power-up

will be at position 63, the low end of the potentiometer. Position 64 is the mute level.

RESISTANCE CHARACTERISTICS Table 1

POSITION

OUTPUT LEVEL (dB)

00

1-1

2-2

3-3

4-4

5-5

63

-63

64(mute)

<-90

DS1801 BLOCK DIAGRAM Figure 1