AN2705

Evaluation board description

3/8

2

Evaluation board description

This board is designed to be tested with a 75

Ω generator and 75Ω measurement tool.

Input signal must be between 0V and 1.4V so that it is not clamped. Otherwise, you must

replace the zero ohm resistor by a 100nF capacitor in CR1, CR2, and CR3, and add a

resistor bridge to polarize the input signal at the right level as shown in Figure 3. Resistor

bridge footprints are located on the back of the PCB.

Figure 3.

TSH173 input

The TSH173 output can be AC coupled by a 220nF capacitor to minimize the DC

component on the line. To do this, you must remove the R4, R11, and R18 zero ohm

resistors and solder a 220µF capacitor on C6, C8, and C10 footprints as shown in Figure 4.

Figure 4.

TSH173 AC output