What does an output impedance of 50Ω mean?
The output impedance of an amplifier is an important factor when dealing with fast signals. The speed of the TZA400 is fast enough for this parameter to be relevant. Essentially, the output of the amplifier is a 50Ω resistance in series with the output. This allows you to terminate the signal line with a 50Ω resistance to prevent back reflections. The result is a clean signal transient without overshoot. The disadvantage is that the signal voltage is halved by doing this. The amplifier may be used without the 50Ω termination resistance, but then there will be overshoot when amplifying fast transients.
What is a BR2 connector?
The outer dimensions and style of connection action of the BR2 connector are identical to BNC. However, instead of one centre pin, the BR2 has two inner pins beside each other (with the shielding braid around both of them). The use of BR2 connectors and shielded, twisted pair cable reduces noise considerably when measuring remote current sources in a noisy environment.
How can I measure a grounded source?
In order to measure a grounded source, the amplifier must have a single ended input configuration. You may use either the BNC or BR2 receptacle.
What is a differential input?
Often we think of a current source as having only one connection, however the other connection is just as important: it is the current return path. A differential input has an active amplifier input for both connection points to the current source. The outputs of these two amplifiers are then electrically subtracted. This has the effect of doubling the signal voltage (since the return path current is of opposite polarity), but cancels any noise components which were equal on both electrodes (“common mode” noise).