Model 7002Switch System Instruction Manual - Advanced Test ...

Front Panel OperationPin 7 - Digital Output #2Pin 9 - Digital Output #4Pin 8 - Digital Output #310Ω+5VPin 4 - External Voltage Flybackconnection (+5V to +30V)Digital OutputFlyback Diodes10kΩPin 6 - Digital Output #1Pin 8 - Digital Output #3Pin 7 - Digital Output #2Pin 9 - Digital Output #4Pin 5 - Digital GroundFigure 4-14Digital I/O port simplified schematicDigital I/O Receptacle5 19 6(Connector J1006)+5V OutputA +5V output is available at pin 2 of the digital I/O connector(J1006). An internal 22Ω resistor is in series with the connectorpin.In order to maintain a minimum TTL level (4.75V), do notuse a load that will draw more than 11mA. Currents above11mA will pull down the voltage below the TTL minimum.Current at this pin will limit at ~225mA.CAUTIONNEVER connect pin 2 (the +5V OUT-PUT) to higher voltages. Voltages at pin2 exceeding ±5V may cause damage tothe Model 7002’s internal circuitry.Outputs used as logic inputsTo use the digital outputs as logic inputs to active TTL, LowpowerTTL, or CMOS inputs:1. Connect the Model 7002 digital outputs to the logic inputs.2. Connect the digital grounds.3. Using the OUTPUT-STATUS menu, check the settingof the Model 7002 output lines. The OUTPUT-STATUSvalue for each output used should be ON.4. Using the OUTPUT-POLARITY menu, check thelogic-sense setting of the Model 7002 output lines(TTL1 through TTL4). Make sure the correct LOGIC-SENSE value is selected for each output line. TheLOGIC-SENSE value varies according to the type ofTTL, Low-power TTL, or CMOS inputs used (AC-TIVE-HIGH or ACTIVE-LOW).When low (0V), the output sink can drive at least 10 standardTTL inputs. When high (+5V), the 10kΩ pull-up resistor willsource >100µA while remaining at a >3.75V output (a reliablelogic high).4-55