DS1802

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SINGLE PUSHBUTTON CONFIGURATION Figure 2(a)

DUAL PUSHBUTTON CONFIGURATION Figure 2(b)

Contact closure is defined as the transition from a high level to a low level on the contact closure input

terminals. The DS1802 interprets input pulse widths as the means of controlling wiper movement. A

single pulse input over the UCx or DCx input terminals will cause the wiper to move one position. A

transition from high to low on these inputs is considered the beginning of pulse activity or contact

closure. A single pulse is defined as being greater than 1 ms but lasting no longer than a second. This is

shown is Figure 4(a).

Repetitive pulsed inputs can be used to step through each resistive position of the device in a relatively

fast manner (see Figure 4(b)). The requirement for repetitive pulsed inputs is that pulses must be

separated by a minimum time of 1 ms. If not, the DS1802 will interpret repetitive pulses as a single pulse.