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从上述分析可知,开关管导通时间的长短,与C_(607)两端的电压以及C_(810)的正向放电时间有关。开关管的导通时间与输出电压成正比例关系。这一自激振荡过程我们称之谓自由振荡过程。 C_(814)两端的电庄建立以后,Q_(842)和Q_(803)开始工作。由于Q_(602)并联在开关管的发射结,所以Q_(802)的工作状态也影响到C_(810)的充放电时间。此时,开关管进入受控振荡(稳压)状态。当市电电压波动或负载电流变化使输出电压上升时,由R_(810)、R_(811)、R_(812)分压,R_(811)可调端获得的取样电压也升高。该电压加在Q_(803)的输入端,与接在Q_(803)发射极的基准电压(D_(807))比较后,产生的误差电压使比较放大器Q_(803)的集电极电流增加。此时Q_(803)的集电极电
It can be seen from the above analysis that the turn-on time of the switch is related to the voltage across C 607 and the forward discharge time of C 810. Switch on-time and output voltage is proportional to the relationship. This self-oscillation process we call free-oscillation process. After the power bank at C_ (814) is established, Q_ (842) and Q_ (803) begin to work. Since Q_ (602) is connected in parallel with the emitter of the switch, the operating state of Q_ (802) also affects the charging and discharging time of C_ (810). At this point, the switch into the controlled oscillation (regulator) state. When the mains voltage fluctuates or the load current changes to increase the output voltage, the sampling voltage obtained from R 810, R 811, R 812 and R 811 is also increased. This voltage is applied to the input of Q_ (803) and compared to the reference voltage (D_ (807)) connected to the emitter of Q_ (803), the resulting error voltage increases the collector current of the comparator amplifier Q_ (803). At this time Q_ (803) of the collector