LTspice电子线路模拟教程 - 图文 下载本文

3.8. Current Measurements

Make the circuit diagram window active.(...by a left mouseclick on it....) and move the cursor exactly over thecomponent of which you want to know the current. The cursor changes to a \mouseclick on the component you will see the trace current displayed in the waveform viewer..

Example:

Current in resistor R1 (Collector resistor of the left transistor, Q2):

3.9. Changing Component Values

Now we want to repeat the simulation with different component values. Let every capacitor be C = 1000pF andboth base resistors of the transistors R3 = R4 = 221( .

Close the Waveform Viewer (if it is open) and activate the schematic window. For each component place thecursor exactly on its value field (the cursor will change to an \dialogue box will appear so you can modify the value. Close each change with OK.

This is the new circuit to be simulated....

....and this should be the simulation result after selecting the collector of Q2 to view the trace:

Use the zoom function or modify the simulation time to see the details or to measure the new oscillationfrequency.

4. 我的第一个.RC-低通模拟任务.

+ 是转动元件.90度.大手是移动元件.

选电压源.,铅笔为画线用.

点C可给予数据.

我们给以10 nF

对电源,你看你是在时间域里还是在频率域里模拟..在此基础上定数值. 我们的RC电路是想.在时间域对电压响应.