I am new to 555 Timers and Proteus and I need help to fix a circuit I have built. The intended function of the circuit is as follows.
I have used Proteus to simulate but I get the error below.
I have reason to believe it arises due to incorrect isolation of the 555 timer outputs (logic gate that is combining the U1, U2 and U5 outputs) but I have been unable to find a solution. I have also considered connecting logic toggles at pin 4 instead of using VCC to switch the timers on. I am unsure if that is a better way to control which 555 Timer outputs a signal though.
It should also be noted that MCUs cannot be used. I would appreciation any suggestions to solve this.
- The logic is controlled by an external circuit but it is represented by switches within this circuit to purely test the 555 Timer functionality. The switches are user controlled in this circuit and they control which 555 timer must be turned on when logic 1 (ie. SW1/SW2/SW3 connected to VCC) is detected.
- Only one 555 timer must function at any time as each 555 timer output has been configured with the use of resistors and capacitors to roughly drive the 24W 220V motor (depicted as a lamp) at respective speeds. The speeds configured by U1, U2 and U5 should roughly be 80V, 150V and 220V.
- To illustrate an example, if U1 is switched on by logic 1 (ie. SW1 connected to VCC), the motor must be driven at 80V. U2 and U5 will be switched to logic 0 (ie. SW2 and SW3 connected to ground).
I have used Proteus to simulate but I get the error below.
I have reason to believe it arises due to incorrect isolation of the 555 timer outputs (logic gate that is combining the U1, U2 and U5 outputs) but I have been unable to find a solution. I have also considered connecting logic toggles at pin 4 instead of using VCC to switch the timers on. I am unsure if that is a better way to control which 555 Timer outputs a signal though.
It should also be noted that MCUs cannot be used. I would appreciation any suggestions to solve this.
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