TSH345

Using the TSH345 to drive Y-C, CVBS, Y-U-V, Y-Pb-Pr and R-G-B video components

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4.1

Output capacitor

The output can be either DC-coupled or AC-coupled. The output can be connected to the

line via a 75-ohm resistor directly (see Figure 5). Or, an output capacitor can be used to

remove any DC components in the load. Assuming the load is 150-ohm, a coupling

capacitor of 220 µF can be used to provide a very low cut-off frequency close to 5 Hz (see

Figure 6).

Figure 5.

DC output coupling (1 of 3 channels)

Figure 6.

AC output coupling (1 of 3 channels)

1.

2.

The 75-ohm resistor must be as close as possible to the output of the driver to minimize the effect of

parasitic capacitance.

75

Ω

75

Ω Cable

75

Ω

Video

DAC

150

Ω

+5V

TSH345

C=220µF

+

75

Cable

75

Video

DAC

150

75

C

S

+5V

TSH345