I decided to change the resistors used so that the device can work with microcontroller ADCs. The ADC of the atmega328p of Arduino Uno microcontroller was considered.
A large simulation 100 Mega ohmload resistor was added at the output to simulate the input resistance of the ADC of the atmega328p.
Resistances of the resistors connected in series to path to circuit ground from output were changed to 1k,3k,7k,9k and track resistor was changed to 20k. These resistances were changed in order to have the output impedance of the circuit be 10k ohms at the resistor combination that gives max voltage. The output impedance needs to be 10k or less since the ADC of the atmega328p is optimized for signals that have an impedance of 10k or less.
The total cost of making 5 pcb prototypes would be TBD not including shipping cost and not including tubing to contain pcb prototype and push button when bent.
Parts List + Total Cost
- 5x FlexPCB ,
- 10x RMCF1206FT20K0 20k SMT Resistor,
- 5x RC1206FR-079K09L 9k SMT Resistor,
- 5x RC1206FR-077K15L 7k SMT Resistor,
- 5x RMCF1206FT3K00 3k SMT Resistor
- 5x CRCW12061K00FKEAC 1k SMT Resistor
- 20x KSR221GNCLFS SPST-NC Tactile Switch, $12.80
Most Expensive to Least Expensive Items
- FlexPCB
- SPST-NC Tactile Switches
- 20k, 9k, 7k, 4k, 3k, 1k SMT Resistors
URL for Parts
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