Hello,
I've built a simple peak detector circuit that is meant to output as DC the peak input voltage. It works just fine when the input stays below around 56 volts, but above that the output appears to saturate at roughly 6.4 V.
The actual input this circuit is expecting is a series of short positive pulses (~100µs @ 10 Hz), and there is potentially some DC drift at the input so I've added a high-pass stage. The input peak voltages can be set to anywhere from 100mV to 10 V, and the rail-to-rail voltage is 1516 V (a 9V and 7660S chip*).
Again, everything is just fine for lower voltages, but my two questions are:
1) Why does the output saturate at 6 V for high input voltages?
2) Why is the output's rise time nice and fast for inputs of 3 V or less, but steadily slower and slower for higher input voltages?
I've attached an image of the circuit with some component specs and model numbers.
Thanks for reading, and any thoughts on this would be terrific!
(*when I tried it with just the 9V and no 7660, the same thing happened, just at a slightly lower voltage: ~5 V)
I've built a simple peak detector circuit that is meant to output as DC the peak input voltage. It works just fine when the input stays below around 56 volts, but above that the output appears to saturate at roughly 6.4 V.
The actual input this circuit is expecting is a series of short positive pulses (~100µs @ 10 Hz), and there is potentially some DC drift at the input so I've added a high-pass stage. The input peak voltages can be set to anywhere from 100mV to 10 V, and the rail-to-rail voltage is 1516 V (a 9V and 7660S chip*).
Again, everything is just fine for lower voltages, but my two questions are:
1) Why does the output saturate at 6 V for high input voltages?
2) Why is the output's rise time nice and fast for inputs of 3 V or less, but steadily slower and slower for higher input voltages?
I've attached an image of the circuit with some component specs and model numbers.
Thanks for reading, and any thoughts on this would be terrific!
(*when I tried it with just the 9V and no 7660, the same thing happened, just at a slightly lower voltage: ~5 V)
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