Abstract: A probe card is provided. The probe card can serialize, analogize and divide a digital signal by a analog-to-digital converter (ADC), a digital-to-analog converter (DAC), and a power divided unit respectively. The probe card can increase signal channels, and is not restricted by signal channels of a tester to test more DUTs simultaneously. Moreover, the probe card has fine impedance matching and channels separating to raise testing efficiency and reduce signal loss.

Abstract: A probe card is provided. The probe card can serialize, analogise and divide a digital signal by a parallel-to-serial converter, a parallel-to-serial converter, and a power divided unit respectively. The probe card can increase signal channels, and is not restricted by signal channels of a tester to test more DUTs simultaneously. Moreover, the probe card has fine impedance matching and channels separating to raise testing efficiency and reduce signal loss.

Abstract: The mini multilayer band-pass filter for balanced to unbalanced signal transformation includes a multilayer substrate and multiple coupling transmission lines. The multiple coupling transmission lines can be formed on one layer of the multilayer substrate or respectively formed on the corresponding layers. Every two of the coupling transmission lines are coupled in order to form a band-pass filter. The first coupling transmission line is configured with an unbalanced input terminal and the last coupling transmission line is configured with two balanced output terminals. With this configuration, a conventional balanced to unbalanced transformer is not necessary to be configured between the band-pass filter and the post circuit. Hence a volume of the circuit can be reduced, and also a loss of the signal transformation can be reduced. Further, a noise of a coupling effect generated between the filter and the balanced to unbalanced transformer can be avoided.