PHD User Guide
10
3. Inputs
The PHD has digital, frequency, and analog inputs.
Damage to equipment!
Do not connect inputs directly to unprotected inductive loads
such as solenoids or relay coils, as these can produce high voltage spikes that may
damage the PHD. If an inductive load must be connected to an input, use a protective
diode or transorb.
3.1. PHD28 Inputs
The PHD28 has up to 7 analog inputs:
•
GPIO1
through
GPIO7
Analog inputs are typically used to read electrical signals that span a voltage range.
Depending on the PHD model, certain inputs can also be configured as inputs for the wake-up
functionality. On the PHD28, Touch, CAN1, and GPIO 1 through GPIO7 can be configured for wake-up
functionality.
Additionally, certain inputs can be configured as low power outputs. See section 3.4 for more
information.
The different configurations are done in software.
3.2. PHD50 Inputs
The PHD50 has up to 8 analog inputs:
•
GPIO1
through
GPIO8
Analog inputs are typically used to read electrical signals that span a voltage range.
Depending on the PHD model, certain inputs can also be configured as inputs for the wake-up
functionality. On the PHD50 the wake options are, Touch, CAN and GPIO1 through GPIO8. Wake on
GPIO9 and GPIO10 is allowed on the PHD50 only if an encoder is not selected, or the FIN input is not
selected. On the PHD50 PF, with the extended wake/sleep functionality, only GPIO1 can be used as a
wake signal.
Additionally, certain inputs can be configured as low power outputs. See section 3.4 for more
information.
The different configurations are done in software.
On the PHD50,
GPIO 9
and
GPIO10
can be configured as a single frequency input on
GPIO9
, or a single
quadrature encoder input on
GPIO9
and
GPIO10
.
The encoder inputs are provided for the uses of a rotary encoder as an input device. The encoder states
must change 4 times, or once per detent in the shaft rotation to be recognized by the PHD50, see chart
below for the required waveform.
Figure 3.1. X2 encoder waveform
X4 encoder waveform