16 analog inputs to the Sequencing ADC

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MiRo_263836
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Level 5
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I am trying to get 16 analog inputs into the Sequencing ADC in Creator.  The ADC configuration allows, but I can't get it to route.  I can get as many as 12 inputs. Once I go to 13 it fails.  It looks like it should be possible. When I add P9.4, it can't find a route.

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Configure your ADC to have only one channel. Then connect it to the Analog Mux component. This component can have as many inputs you need. You need to manually switch the Analog Mux to the desired channel after every sample.

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ShipingW_81
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Possible to attach your project?

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I can't find how to attach a file to this discussion.  It is just a 16 sequencing ADC targeting the PSOC6 BLE Module (CYBLE-416045).  Creator 4.2.  I updated the devices, components and PDL 3.1.0

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If it doesn't fit in the module, can you see if it will fit in a PSOC6 BLE (any 6300)? I have tried both and it won't route

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You can't have all 16 channels connected to pins. Some of them will be connected through the OpAmp. One will be connected to the DieTemp.

If you need actually 16 channels from external pins, you need to use the global analog mux.

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OK.  I need 16 external inputs. I am not using the OpAmps or Die Temp. So how do I use the global mux?

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Configure your ADC to have only one channel. Then connect it to the Analog Mux component. This component can have as many inputs you need. You need to manually switch the Analog Mux to the desired channel after every sample.

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That did it.  It would have been better to be the scanning ADC, but I can work around it. This saves an external analog mux. I can use the sequencing mux and use AMuxSeq_Next() to sequence the inputs.

Thank you.

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You might be able to have a mix of both. You can add as many channels in the SAR ADC you can + the injection channel. Connect then the analog mux component to the injection channel of the SAR ADC.

This would work if you have some lower priority channels, so they can be connected to the analog mux component. The higher priority channels are connected directly to the SAR ADC sequencer.

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I have done that before on the PSOC4 and it worked it well with lower priority signals being fed to the mux. The issue with that is that you can't have a mux feeding a mux (the scanning input is a mux). The routing algorithm can't resolve that. The workaround was to bring the amux output to a pin which routes the amux and then feed to the INJ channel.  

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n this case, they are all equal.  This may be a way to make it faster.  I will investigate and see if I need to do the same thing.

Thanks for your help.