What is the equation switched capacitors

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dddd12349999
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HELLO
what is the equation that describes the relation between the charging current i(vdd) and that switched capacitors ( c1,c2,c3,c4,c5) if we put into consideration that switches are closing in sequence switch 1,switch 2, . . .switch 5 with a delay time of td


thanks
 
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  • Circuit schematic of five capacitors C1 to C5 in parallel, each with a series switch to a common top rail fed from vdd through resistor R, with the current labelled i_vdd and a ground symbol on the bottom rail.
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There is a problem with your circuit.
When the second capacitor is switched, there is an infinite current through the switch.
 
can we think about it as a variable capacitor?
 
dddd12349999 said:
HELLO
what is the equation that describes the relation between the charging current i(vdd) and that switched capacitors ( c1,c2,c3,c4,c5) if we put into consideration that switches are closing in sequence switch 1,switch 2, . . .switch 5 with a delay time of td

thanks
Circuit schematic of five capacitors C1 to C5 in parallel, each with a switch in series, connected between a top rail fed by vdd through resistor R and a bottom rail tied to ground.



Carl Pugh said:
There is a problem with your circuit.
When the second capacitor is switched, there is an infinite current through the switch.
That's only for an instant.

When the switch for C2 is closed, the voltages across C1 & C2 become equal to each other virtually instantaneously. Then the pair continue to be charged for that point.