General Purpose Inputs And Outputs; Figure 2-2: Gpi Circuitry; Figure 2-3: Gpo Circuitry - evertz 7700 Manual

7700 MultiFrame Manual
7735AVC-LB Video Composite Encoder and Audio DAC with SoftSwitch

2.3.2. General Purpose Inputs and Outputs

The GPIs are active low with internal pull up resistors (4.7kΩ) to +5V. To make an input active, lower the
signal to near ground potential (i.e. connect to shell or chassis ground). This can be done with a switch,
relay, TTL drive, GPO output or other similar methods. Figure 2-2 illustrates the input circuit for the
General Purpose Inputs:
+ 5 Volts
4.7 kΩ
To Internal
Circuit
GPI
GND

Figure 2-2: GPI Circuitry

The GPO is software programmable active high or low with internal pull up (10kΩ) resistors to +5V. When
the output goes low it is able to sink up to 10mA. When high, the signal will go high (+5V). Do not draw
more than 100µA from the output. Figure 2-3 illustrates the circuit for the General Purpose Output:
+ 5 Volts
10k Ω
10 Ω
GPO
From Internal
Circuit
GND

Figure 2-3: GPO Circuitry

7735AVC-LB - 6
Revision 1.6