Agilent Technologies U2761A manual Output Termination, Features and Functions

2 Features and Functions

Output Termination

This configuration applies to output amplitude and offset voltage only. The U2761A has a fixed series output impedance of 50 Ω to the device output connector. If the actual load impedance is different from the specified value, the amplitude and offset levels will be incorrect.

•The range of the output termination is 1 Ω to 10 kΩ, or Infinite. The default value is 50 Ω.

•The output termination setting is stored in volatile memory and upon power-off or after a remote interface reset, the setting will return to a default value.

•If you specify a 50 Ω termination but are actually terminating into an open circuit, the actual output will be twice the value specified.

For example, if you set the offset to 100 mVDC (and specify a 50 Ω load) but are terminating the output into

an open circuit, the actual offset will be 200 mVDC.

•If you change the output termination setting, the output amplitude and offset levels are automatically adjusted (no error will be generated).

For example, if you set the amplitude to 5 Vpp and then change the output termination from 50 Ω to “high

impedance”, the amplitude value will double to 10 Vpp. If you change from “high impedance” to 50 Ω, the displayed

amplitude value will drop to half.

•You cannot specify the output amplitude in dBm if the output termination is currently set to “high impedance”. The units are automatically converted to Vpp.

36 U2761A User’s Guide