Input Signals - Agilent Technologies 4349B Manual

4349B
Figure B-2. Handler Interface Control Output Signals Diagram

Input Signals

The DC isolated input signals are connected to the cathodes of the LEDs in the opto-isolators.
The anodes of the LEDs are powered by an external voltage source (EXT DCV2).
The OFF state voltage (high level) of the DC isolated input signals depends on the pull-up
voltage powered by an external voltage source (EXT DCV2). (The input current is restricted by
using a switch on the main board.)
The electrical characteristics of the input signals are listed in Table B-2. A diagram for the
input signals is shown in Figure B-3.
Signal
/EXT TRIG
/KEY LOCK
Table B-2. Handler Input Electrical Characteristics
Input Voltage
Low High

1 V 5 to 15 V 8.7 mA 10.5 mA 13.5 mA

1 V 5 to 15 V 7.7 mA 10.8 mA 13.6 mA
Input Current (Low)
Pull-up Voltage
5 V 12 V 15 V
Circuit
Common
COM2
COM2
Handler Interface Installation B-3