other input, and this effect increases with frequency. Channel isolation is a measure of how much crosstalk occurs between
the two probe inputs. The channel isolation is defined with S-parameter measurements below, where:
A input = S1, B input = S2, Output = S3
A ISOLATION = 20 log (S
31
/S
32
) | A Mode
B ISOLATION = 20 log (S
32
/S
31
) | B Mode
A typical isolation plot for the TDP7700 Series probes using a TekFlex solder tip is shown in the following figure. When the
probe is used with TekFlex solder tips, note that channel isolation performance is highly dependent on probe tip attachment
lead length. Good channel isolation requires keeping the interconnect lead length for both signal and ground connections
very short.
Figure 26: Typical channel isolation
Reference
TDP7700 Series TriMode™ Probes Technical Reference
22
