CD22101

CD22101 and CD22102 crosspoint switches consist of 4 x 4 x 2 arrays of crosspoints (transmission gates) with a 4-line to 16-line decoder and 16 latch circuits. Any one of the sixteen crosspoint pairs can be selected by applying the appropriate four-line address, corresponding
crosspoints in each array are turned on and off simultaneously. Any number of crosspoints can be turned on simultaneously.

In the CD22101, the selected crosspoint pair can be turned on or off by applying a logic ONE or ZERO, respectively, to the data input, and applying a ONE to the strobe input. When the device is "powered up", the states of the 16 switches are indeterminate. Therefore, all
switches must be turned off by putting the strobe high, data-in low, and then addressing all switches in succession.

The selected pair of crosspoints in the CD22102 is turned on by applying a logic ONE to the KA (set) input while a logic ZERO is on the KB input, and turned off by applying a logic ONE to the KB (reset) input while a logic ZERO is on the K_A input. In this respect, the control latches of the CD22102 are similar to SET/RESET flip-flops. They differ, however, in that the simultaneous application of ONEs to the K_A and KB inputs turns off (resets) all crosspoints. All crosspoints in both CD22101 must be turned off as V_DD is applied.