Dear all, I am using multisim 10.0 to simulate the switched cap charge amplifier (SC.bmp). When I put this circuit in a seperate file, the amplifier output waveform is correct. However, if I copy the circuit to another file which contain a 8051, then the amplifier output tends to be pulled up to power supply. Finally I want to use 8051 to control the switch instead of using the pulse voltage generator. But in this stage, I don't do this connection, just simply copy the original circuit to this 8051 file. I don't know why this generates different output waveforms. Anyone could give me some suggestions or solutions? Thanks a lot.
Here I upload all the file:
SC.bmp------simple switched cap charge amplifier circuit
SC.ms10----simple switched cap charge amplifier circuit multisim file
SC_Osi.bmp-----simple switched cap charge amplifier output waveform
switched_cap_test_2.bmp----copy the circuit to a file containing 8051
switched_cap_test_2.ms10-----multisim file
switched_cap_test_2_Osi.bmp---amplifier output file
FP_Switch_Cap.hex----hex file for 8051
