MultiCam Boards Documentation > DOMINO series Documentation > DOMINO Symphony Handbook > Board Specifications > DC/AC Characteristics > Factory Inputs - IN1...IN4

Factory Inputs - IN1...IN4

There are four professional input ports on factory I/O connector. The ports are named IN1, IN2, IN3, and IN4.

SymphonyFactoryInputsEqSch

Factory Inputs

Each port has two pins named respectively INi-A and INi-B; with i = {1, 2, 3, 4}. This digital non-isolated differential input is polarity insensitive and is able to interpret TTL, high voltage and contact closure.

The I/O controller measure the impedance of the device connected across both inputs. If the impedance is above 4 kΩ, the VIOS concludes that the circuit is open and returns an OPEN state. If the impedance is below 4 kΩ, the I/O controller measures the voltage present.

If the measured voltage is above the voltage threshold (Vth), the IO controller returns a HIGH state. If the measured voltage is below Vth, the VIOS returns a LOW state. The voltage threshold Vth can take two values (1.5V and 6V).

Hint: The capability to detect an open state can be advantageously used with TTL or high voltage signaling to detect a line that is abnormally broken.

DC Specifications

Parameter

Min

Typ.

Max

Units

Open threshold

2

4

9

Measurement current

 

±130

 

µA

Voltage threshold (TTL)

1

1.5

2

V

Voltage threshold (12V)

5

6

7

V

Maximum differential input voltage (not operating)

 

 

±27

V

Maximum input voltage (not operating)

-27

 

+27

V

Input voltage range to correctly interpret OPEN/CLOSE states on contacts

-3

 

+6

V

Input voltage range to correctly interpret HIGH/LOW states on 5V signals

-11

 

+14

V

Input voltage range to correctly interpret HIGH/LOW states on 12V signals

-11

 

+14

V

Input voltage range to correctly interpret HIGH/LOW states on 24V signals

-24

 

+26

V

Common mode noise immunity from DC to 20MHz (filter set to 100ms)

8

 

 

V

AC Specifications

Parameter

Min

Typ.

Max

Units

Input state sampling period

 

4

 

ms