Digital I/O; Digital Inputs - Z-World Fox LP3500 User Manual

3.3 Digital I/O

3.3.1 Digital Inputs

The LP3500 has 16 digital inputs, IN00–IN15. The inputs are factory-configured to be
pulled up to +K in banks of eight, but they can also be pulled up to Vcc or down to 0 V in
banks of eight by changing a surface-mounted 0 Ω resistor as shown in Figure 9.
GND
Figure 9. LP3500 Digital Inputs [Pulled Up—Factory Default]
The digital inputs are each fully protected
over a range of 0 V to +36 V, and can
handle short spikes of ±40 V. The actual
switching threshold is approximately
1.40 V. Anything below this value is a
logic 0, and anything above is a logic 1
Pulling the digital inputs to Vcc will in-
crease the current consumption by about
300 µA for each digital input.
22
Vcc
+K
0 W
22 kW
100 kW
330 nF
+40 V
+36 V
.
+3.3 V
–40 V
Figure 10. LP3500 Digital Input Protected
Rabbit 3000 ™
Microprocessor
Range
Fox (LP3500)