凌力尔特公司推出 LTspice IV ,这是其免费 SPICE 电路仿真软件所做的一次重大更新。LTspice IV 具有专为提升现有多内核处理器的利用率而设计的多线程求解器。另外,该软件还内置了新型 SPARSE 矩阵求解器,这种求解器采用汇编语言,旨在接近现用 FPU (浮点处理单元) 的理论浮点计算限值。当采用四核处理器时,LTspice IV 可将大中型电路的仿真速度提高 3 倍。
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 "I beam") and right click with the mouse. Adialogue 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.