STV7622

Circuit description

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Spread Spectrum: To avoid having too large of a current in the driver during the rising edge

of the power outputs, all outputs are not triggered at the same time.

Instead, the STV7622 inserts a small delay between the rising edge of two consecutive

outputs. This delay depends on picture or image content (see Figure 8). For a dark picture,

The SSJ function spreads the discharge current in the scan lines and, therefore, reduces

EMI by “spreading” the energy spectrum.

Figure 8.

Spread spectrum filter

OUT-1

OUT-x

t

SSJ-MIN

t

SSJ-MAX

OUT-1

OUT-x

Case #1: Dark picture

Case #2: White picture