Analysis of maintenance: direct observation can be seen on the output of the circuit board and circuit traces of maintenance, estimated failure likely to occur in this part. Power MOs power amplifier uses two IRF640N tubes, drive uses a half-bridge driver IC IR2111, form a class d amplifier circuit. This part of the circuit as shown in Figure 2.Wudservice manual download site
Wudservice manual download site
Check the relevant components, finding power Q18, Q22, Q19, Q23, D28 and the damage, and IR2111 cannot be ascertained, after electrifying contrast fix E150P OK. For safety's sake, do not install the power MOs tubes were measured. Taking into account the working voltage factors results BP 12 IR2111 some feet on the voltage varies with the E150P, check around and found no problems of power supply circuits, suspect IR2111 is damaged,Wudservice manual download site
Wudservice manual download site
But when the power measured on each pin of the resistor, IR2111 contrast with the E150P is not much different. In the case of unable to determine the good from the bad, on-line searchable information on IR2111, discovered the IR2111 high pressure side suspended driver bootstrap principle, its suspension power is obtained by using bootstrap circuit. C65, D26, respectively, in Figure 2 to charge the bootstrapped capacitor and diode. When the IR2110 is used to drive the half-bridge circuit, through IR2111 internal circuitry combined with switching power MOs tubes on C65 bootstrap capacitor charge and dischargeWudservice manual download site
Wudservice manual download site
To obtain the suspending power supply voltage, so, you must install the power MOs IR2111 to detect a normal working voltage, because has not encountered a similar circuit, according to conventional methods of detection, measurement results are incorrect, fitted with power MOs tube before measurement, foot normal working voltage of IR2111, Horn audition results are normal.Wudservice manual download site