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FUNCTION BLOCK
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DESCRIPTION
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- Limits an input signal to a set voltage.
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CIRCUIT DETAILS
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DC Voltage Clamp
- The output will not rise above the voltage of the zener diode.
- Maximum input voltage is around 18 volts. Increase R1 to 2.2K for input voltages over 20v.
- The output will not have a very high current capability and should be buffered or fed to a high impedance input.
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DC Voltage Clamp Circuit
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AC Voltage Clamp
- The zener diodes should be 0.7 volts less than the maximum required voltage - this is due to the forward voltage drop of diodes when forward biased.
- So for 5v clamping, use 4.3 volt zener diodes.
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AC Voltage Clamp Circuit
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| Written by Phil Townshend - 2008 |
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www.edutek.ltd.uk - Working Electronics For Students & Teachers
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