TDA9111 datasheet(28/43 Pages) STMICROELECTRONICS

Part #	TDA9111

Description	LOW-COST I2C CONTROLLED DEFLECTION PROCESSOR FOR MULTISYNC MONITOR

PDF	43 Pages

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Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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TDA9111

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This protection is latched; it may be reset either by

VCC switch-off or by I

2C (see Figure 14 on

page 28).

2.6 Horizontal and Vertical Dynamic Focus

For dynamic focus adjustment, the TDA9111 de-

livers the sum of two signals on pin 10:

– a parabolic waveform at horizontal frequency,

– a parabolic waveform at vertical frequency.

The horizontal parabola comes from a sawtooth in

phase advance with flyback pulse middle. The

phase advance versus horizontal flyback middle is

kept constant versus frequency (about 1

µs).

Symmetry and amplitude are I2C adjustable (see

Figure 15 on page 29). The vertical parabola is

tracked with VPOS and VAMP. Its amplitude can

be adjusted. It is also affected by S and C correc-

tions. This positive signal once amplified is to be

sent to the CRT focusing grids.

Because the DC/DC converter is triggered by the

HFocus sawtooth, it is recommended to connect a

capacitor to pin 9, even if HFocus is not needed.

Figure 14. Safety Functions Block Diagram

TDA9111 Datasheet(PDF) 28 Page - STMicroelectronics