Oscillating circuit

C847 nearly 300V DC voltage through storing transformer primary winding P1, P2 is added to the IC801 (3) internal foot switch tube very C, also added to the R803 IC802 (2) internal foot switch tube B, so that switching tube open conduction. In this way, P1 and P2 winding voltage coupling to F2, F3 winding and generated positive feedback voltage by which is, R804 and call IC801 (2) and (4) foot (i.e., internal switch tube B, e feet), and switch quickly saturated.

Switch transistor saturation during, the current from the foot (4) of the IC801 outflow, establish 113V DC voltage in the C808, also T801 stored magnetic energy. At this time, due to the feedback capacitor which is constantly charging, IC801 (2) internal foot switch tube voltage is more and more low, when fell to sustain the switch transistor saturation, switch tube will withdraw from the saturated state C very current decreases, cause T801 the winding induction voltage polarity reversed all, F2, F3 winding voltage and which is, R804 enable switch tube cut-off quickly.

Switch tube after the deadline, which is the R805, D806, F3 and F2 winding discharge. At the same time 300V voltage by R803 to which is reverse charging, the IC801 (2) feet potential rise. At the same time, (2) foot of the flyback pulse is transferred to a IC801 by D805. End of the switch tube that deadline, by positive feedback and into the saturated state, so the formation of oscillation.

Regulator circuit

Voltage regulator STR50213 internal power routing.

Protection circuit

Q834 for 113V over-voltage protection circuit, when the 113V is normal, Q834 cutoff, such as 113V is too high, then the Q834, the 113V is short circuit, switching power supply.

Q851 for 12V short-circuit protection circuit, such as 12V short circuit, the Q851 conduction, Q814 cut off, at this time is equivalent to remote control.

M15l movement and a few road protection, are for the IC601 (42) foot, and this is not discussed.

Auxiliary power supply and remote shutdown circuit

When the boot, CPU (6) pin output high level, so that the Q814 Q810, Q811, Q812,, Q813 are off, auxiliary power is not working.

When it is in standby mode, the CPU (6) pin output low level, the cut-off q814, Q811 conduction, IC801 (5) pin by R853 grounding, main power circuit stop work, on the other hand, 300V DC voltage by R809 r810 to Q810B very provide bias current, Q810 conduction, Q810 current flowing through R815, D813 indicator, D814 C811 generate 5V DC voltage, as the power supply voltage of the CPU. Q813 is the 5V power supply voltage regulator circuit, by R812, D810 constitute the 4.3V benchmark circuit, to provide the E 4.3V Q813 reference voltage, B Q813 R811 is provided by the 5V sampling voltage, D811 for 10V stable 10V pressure tube.