摘要 |
An analog test probe includes an integrated circuit having a large number of separate channels, each connected to one of its inputs. There is a plurality of probe tips and 100 ohm coaxial cables, each cable connecting one of said probe tips and one of the IC inputs. This structure introduces reverse signals into the channels that would seriously degrade probe operation if not removed. A capacitor and resistor in each probe tip, and in series with the coaxial cable and ground, match the impedance of the coaxial cable in the reverse direction, so that reverse signals are dissipated in the resistance and capacitance and do not reflect into the probe channels.
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