Rainbow Electronics DS1802 - Manual (Page 5)

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 lo nger 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.