Polycom SoundStructure C16 Hardware Installation Manual page 29

Chapter 4 Logic Examples provides an example of how to use the analog gain
input pin.
SoundStructure Logic Input
Analog
Voltage
Value
Logic Outputs
All logic outputs are configured as open-collector circuits and may be used
with external voltage sources. The maximum voltage that should be used with
the logic outputs is 60 V with a maximum current of 500 mA.
SoundStructure Logic Output
Controller
The open collector design is shown in the following figure and works as a
switch as follows: when the logic output pin is set high (on), the transistor will
turn on and the signal connected to the logic output pin will be grounded and
current will flow from the logic output pin to chassis ground.
Installing The SoundStructure C16, C12, C8, And SR12
5V
Logic
Chassis
Ground
Logic Pin 1 (+5V)
Analog Gain Input Pin
Logic Pin 25 (Ground)
Logic Output Pin
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