Re: Reprap Arduino Due Shield project - looking for helping eyes. April 27, 2013 06:09AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 27, 2013 07:20AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 27, 2013 11:21AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 27, 2013 11:32AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 27, 2013 01:05PM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 28, 2013 06:15AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 28, 2013 06:37AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 28, 2013 07:18AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 28, 2013 07:39AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 28, 2013 10:08AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 28, 2013 10:34AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 28, 2013 11:52AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 29, 2013 03:19AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 29, 2013 07:44AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 29, 2013 09:52AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 29, 2013 07:49PM |
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Quote
The analog input circuitry for single ended channels is illustrated in Figure 26-8. An analog source applied to ADCn is subjected to the pin capacitance and input leakage of that pin, regard- less of whether that channel is selected as input for the ADC. When the channel is selected, the source must drive the S/H capacitor through the series resistance (combined resistance in the input path).
The ADC is optimized for analog signals with an output impedance of approximately 10kΩ or less. If such a source is used, the sampling time will be negligible. If a source with higher impedance is used, the sampling time will depend on how long time the source needs to charge the S/H capacitor, which can vary widely. The user is recommended to only use low impedant sources with slowly varying signals, since this minimizes the required charge transfer to the S/H capacitor."
Re: Reprap Arduino Due Shield project - looking for helping eyes. April 29, 2013 08:36PM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. April 30, 2013 01:51AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 03, 2013 09:54PM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 04, 2013 02:18AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 04, 2013 11:28AM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 04, 2013 12:38PM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 04, 2013 01:13PM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 04, 2013 01:27PM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 04, 2013 01:30PM |
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Re: Reprap Arduino Due Shield project - looking for helping eyes. May 04, 2013 01:35PM |
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Quote
STB
It can be done with a nuch simpler circuit.
The input of the ADC behaves like a capacitor with some pico farads. No static current is flowing into this pin.
In this case, taken into account that the thermistor signals time constant is in the range of some 100ms, a simple series resistor of ~22kOhms followed by ~470nF (against noise) is enough to protect the input against voltages up to 30V. Clamping is done by the internal ESD protection diodes
Quote
Cefiar
On the topic of protection, it would be worthwhile adding diodes on the FET outputs too, such as described in the following thread: [forums.reprap.org]