1. PSPICE 计算机仿真 Simulation Program with Integrated Circuit Emphasis

2. CH3 DC SWEEP ANALYSIS 直流扫描分析

3. 3.1 Sweeping a single source

4. Fig.26

5. Example 2 For the circuit shown in Fig.26, use PSpice to find the values of i o and v o when v g varies from 0 to 100V in 10V steps.(P22)

6. Fig.27

7. Place->Part Analog lib: R Source lib: Vsrc, Isrc Special lib: Iprint (ammeter 安培表 ) Special lib: Vprint2 (voltmeter 伏特表 )

8. 注意事项 : Vsrc 元件 : 参数不需要改动 Isrc 元件 : 选中 Isrc 元件, ( 粉色表示被选中 !) Edit->Properties … 修改 DC 项 : 5, 如图 27a

9. Fig.27a 修改 Isrc 属性

10. Iprint 元件需要执行 Mirror 操作 : : 选中 Iprint 元件, ( 粉色表示被选中 !) Edit->Mirror->Horizontally H 执行 Mirror 操作 Edit->Properties … 修改 DC 项 : Y, 如图 28

11. Fig.28 修改 Iprint 属性

12. Vprint2 元件需要执行 Mirror 操作 : 选中 Vprint2 元件, ( 粉色表示被选中 !) Edit->Mirror->Horizontally H 执行 Mirror 操作 Edit->Properties … 修改 DC 项 : Y, 如图 28a

13. Fig.28a 修改 Vprint2 属性

14. Fig.29 Simulation Settings dialog

15. What does Probe do? We can also depict the results of the DC Sweep analysis graphically, using Probe.

16. PSpice->Run( 如图 29a) View->Output file( 如图 30)

17. Fig.29a Probe 窗口

18. Fig.30 Output file

19. Trace/Add Trace （ Fig.31 ） 注意： Trace Expression: V2(R1)

20. Fig.31 Selecting a variable: V2(R1)

21. Fig.32 the resulting plot

22. 3.2 Sweep Multiple Sources

23. Example 3 The current source in the circuit shown in Fig.26 varies from 0 to 5A in 1A steps. For each value of the source voltage, plot i 0 as v g varies from 0 to 100V in steps of 20V.

24. Solution The schematic is the same as the one in Fig.27. In Capture, select the menu option PSpice/Edit Simulation Settings to specify a Secondary Sweep, the additional sweep variable and its values Fig.33.

25. Fig.33 Simulation Settings dialog 2

26. We also changed the increment in the Primary Sweep from 10V to 20V(Fig.33a).

27. Fig. 33a Simulation Settings dialog 1

29. Trace/Add Trace （ Fig.33b ） 注意： Trace Expression: I(R4)

30. Fig.33b Selecting a variable: I(R4)

31. Fig.34 the resulting plot? (It may be wrong! Please check!)