CTA28 Datasheet, PDF (7/11 Pages) Radiometrix Ltd – CTA88 chip based 2-channel I/O Application Boards

The long timeout is usable with the randomised periodic transmission mode (101), as the 3 second timeout is
longer than the longest delay between transmissions in this mode.
Versions of the chip can be supplied with this period extended to suit customer requirements
CTA28/CTA88 board: External input operation
Option 1 (Default)
LK1A
COM
LK1B
IN
+5V
LK1A will link the COM to the system ground
LK1B will link the +5V to the +5V system rail.
So, just linking the IN and +5V inputs will trigger the operation. It is useful for sliding switch
operation.
Option 2
COM
+5V
IN
OV
+Vcc
COM: Local ground (not connected to system ground)
IN : 4mA Voltage sense
+5V: +5V bias current
Connecting external supply to the COM and IN will trigger the operation
Option 3
LK1A
IN
COM
+5V
+Vcc
LK1A will link the COM to the system ground.
Radiometrix Ltd
CTA28 Demo board
page 7