DescriptionThe TDA8356 is a power circuit for use in 90° and 110° colour deflection systems for field frequencies of 50 to 120 Hz. The circuit provides a DC driven vertical deflection output circuit, operating as a highly efficient class G system.
The vertical driver circuit is a bridge configuration. The deflection coil is connected between the output amplifiers, which are driven in opposite phase. An external resistor (RM) connected in series with the deflection coil provides internal feedback information. The differential input circuit is voltage driven. The input circuit has been adapted to enable it to be used with the TDA9150, TDA9151B, TDA9160A, TDA9162, TDA8366 and TDA8376 which deliver symmetrical current signals. An external resistor (RCON) connected between the differential input determines the output current through the deflection coil.
The relationship between the differential input current and the output current is defined by: Idiff ´ RCON = Icoil ´ RM. The output current is adjustable from 0.5 A (p-p) to 2 A (p-p) by varying RM. The maximum input differential voltage is 1.8 V. In the application it is recommended that Vdiff = 1.5 V (typ). This is recommended because of the spread of input current and the spread in the value of RCON.
The flyback voltage is determined by an additional supply voltage VFB. The principle of operating with two supply voltages (class G) makes it possible to fix the supply voltage VP optimum for the scan voltage and the second supply voltage VFB optimum for the flyback voltage. Using this method, very high efficiency is achieved.
Download Datasheet TDA8356