I am trying to build a bi-directional constant current source with a h-bridge configuration. As you can see in the attached figure, I am controlling the direction of current on the load using PWM command from micro controller. I have tried analog switch ICs(such as CD4016, CD4066) to simulate a +- 1 mA current driver. The simulation works very well, but when I implement this circuit with real electronic components the circuit does not work. Do you have any suggestions or thoughts on this problem. I have to add when I use transistors for switching there is no problem.
I have added another figure for clarification. This is the result of simulation. As can be seen the h-bridge circuit produce -+1mA at the load. V battery + provides the voltage and constant current source control the current. H-bridge circuit change the direction of current by switching on 1,4 in one phase and switching on 2, 3 in the second phase. This circuit produces the -+1mA shown in the picture. But in the real implementation of circuit I can not get any voltage across the load. I use 10 kohm load and measure current by connecting oscilloscope across the load.