Hello Partzman,
Is this the current component layout that you would suggest newcomer's build in order to investigate charge separation with gain?
In general, yes. Let me see if I understand this correctly, Vbias charges C1 to a potential of Vbias through switch M2 and also C2 to a potential of Vbias - V+.
Yes, these are the starting conditions. Switch M2 is turned off and then switch M1 turns on briefly to charge L1 from Vss through precharged C1 and discharging into Vbias and C2 + V+? Does Vbias not need a blocking diode?
First, Vbias does require a blocking diode. So, you are correct with your above comment except the voltage on the positive junction of C1 and C2 rises during the charging of L1 and the blocking diode then decouples from Vbias. M1 switches off and M2 switches back on completing the path for L1 and C1 to continue discharging stored energy into C2 and V+. Presuming that Vbias does need a blocking diode, we now have a higher potential on (C2) + (V+) than we do on C1. This potential then recharges C1 through M2 until it equalizes with Vbias in which case Vbias finishes charging C1 back to a precharged condition?
Your first sentence above is correct. Your second sentence is correct except Vbias does have a blocking diode. The cycle ends when the collapsing current in L1 reaches zero. Therefore, the action in your third sentence does not occur. However, there is a 'reset' phase that sets C1 and C2 back to their starting voltages so another cycle may begin but that will be discussed later. Which direction is the polarity of the induced potential on C1 while L1 is charging?
One must be careful to observe the polarity of the negative end of C1 with respect to L1. Properly following the polarities, the negative end of C1 will first go positive during the time M1 is on by the volts/turn on L1, and then will attempt to to return to zero when M1 is off and M2 is on. The negative end of C1 will then increase in measured voltage until the end of the cycle. Do you have any scope data available for this circuit?
I will supply scope data of a working device for the first cycle later tomorrow. It will be different however in that Vss will be connected directly to V+ for a self powered version. The reset circuity and process will not be shared yet at this time as I want to finish a complete working device first. Thanks,
Dave
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