diff --git a/pcb/DonConIO/README.md b/pcb/DonConIO/README.md index ffc096f..dfac160 100644 --- a/pcb/DonConIO/README.md +++ b/pcb/DonConIO/README.md @@ -12,31 +12,36 @@ You can also try your luck with any generic piezo, in this case you might have t ## Note -This board uses the internal ADCs of the RP2040. Those however are pretty noisy and have a static offset of around +25mV. I'm currently working on a board revision with support for an external ADC and reference voltage source, hopefully improving sensitivity. Stay tuned. +This board does not use the internal ADCs of the RP2040 since those are pretty noisy and have a static offset of around +25mV. You can however still skip the external ADC and level-shifter and connect the signals directly to ADC pins of the XIAO RP2040 if you want to save some cost. ## Bill of Materials -| **Reference** | **Description** | **Digikey Part** | **Notes** | -| ----------------------------------------------------- | :---------------------------: | :----------------------: | :----------------------------------------------------------------------------------------------------------------------------------------------: | -| J6, J7 | Seeed Studio XIAO RP2040 | - | | -| U1, U2, U3, U4 | TL072CP JFET OpAmp | 296-1775-5-ND | | -| PS1 | +/-12V DC to DC Converter | 2725-A0512S-1WR3-ND | | -| C1, C3, C5, C7 | 1nF Mylar/Polyester Capacitor | 493-14299-ND | | -| C2, C4, C6, C8 | 0.47µF Tantalum Capacitor | 478-1901-ND | | -| C9-C16 | 100nF Ceramic Capacitor | BC1084CT-ND | | -| C17 | 4.7µF Electrolytic Capacitor | 1189-1421-ND | | -| C18, C19 | 1µF Electrolytic Capacitor | 50YXJ4.7M5X11-ND | | -| D1, D2, D5, D7, D8, D11, D13, D14, D17, D19, D20, D23 | 1SS133M Small Signal Diode | 1SS133MR0GCT-ND | While the 1SS133M is probably more *authentic*, a 1N4148 will probably just work as well. | -| D3, D4, D9, D10, D15, D16, D21, D22 | BAT43 Schottky Diode | 112-BAT43-TAPCT-ND | | -| D6, D12, D18, D24 | 1N5226B 3.3V 20mA Zener Diode | 1N5226BFSCT-ND | | -| R1, R10, R19, R28 | 1MΩ Resistor | 13-MFR-25FTE52-1MCT-ND | | -| R2, R11, R20, R29 | 4.7kΩ Resistor | 13-MFR-25FRF52-4K7CT-ND | | -| R3, R12, R21, R30 | 100kΩ Resistor | 13-MFR-25FRF52-100KCT-ND | | -| R4, R13, R22, R31 | 100Ω Resistor | 13-MFR-25FRF52-100RCT-ND | | -| R5, R14, R23, R32 | Wire brigde | - | Can be used as a voltage divider together with R6, R15, R24, R33 to scale down the signal before the buffer stage. This will reduce sensitivity. | -| R6, R15, R24, R33 | 5.1kΩ Resistor | 13-MFR-25FRF52-5K1CT-ND | If you add the Resistor for the voltage divider, make sure to reduce this one so the sum stays at 5.1kΩ | -| R7, R16, R25, R34 | 10kΩ Resistor | 13-MFR-25FRF52-10KCT-ND | -| R8, R17, R26, R35 | 1kΩ Resistor | 13-MFR-25FRF52-1KCT-ND | -| R9, R18, R27, R36 | 300Ω Resistor | MFR-25FRF52-300R | -| J1, J2, J3, J4 | 2Pin S2B-PH-K-S Connector | 455-1719-ND | PHR-2 plus SPH-002T-P0.5L is the counterpart | -| J5 | 5Pin S5B-PH-K-S Connector | 455-1722-ND | PHR-5 plus SPH-002T-P0.5L is the counterpart | +| **Reference** | **Description** | **Digikey Part** | **Notes** | +| ----------------------------------------------------- | :--------------------------------------------------: | :-----------------------: | :---------------------------------------------------------------------------------------: | +| J6, J7 | Seeed Studio XIAO RP2040 | - | | +| U1, U2, U3, U4 | TL072CP JFET OpAmp | 296-1775-5-ND | | +| U5 | MCP3204 12bit SPI ADC | MCP3204-CI/SL-ND | | +| U6 | MCP1541 4.09V Voltage Reference | MCP1541T-I/TTCT-ND | | +| U7 | TXB0104 4-Bit Bidirectional Voltage-Level Translator | 296-21928-1-ND | | +| PS1 | +/-12V DC to DC Converter | 2725-A0512S-1WR3-ND | | +| C1, C3, C5, C7 | 1nF Mylar/Polyester Capacitor | 493-14299-ND | | +| C2, C4, C6, C8 | 0.47µF Tantalum Capacitor | 478-1901-ND | | +| C9-C16 | 100nF Ceramic Capacitor | BC1084CT-ND | | +| C17 | 4.7µF Electrolytic Capacitor | 1189-1421-ND | | +| C18, C19 | 1µF Electrolytic Capacitor | 50YXJ4.7M5X11-ND | | +| C20, C22, C24, C25 | 0.1µF SMD Ceramic Capacitor | 1276-1003-1-ND | | +| C21, C23, C26 | 10µF SMD Ceramic Capacitor | 1276-6454-1-ND | | +| D1, D2, D5, D7, D8, D11, D13, D14, D17, D19, D20, D23 | 1SS133M Small Signal Diode | 1SS133MR0GCT-ND | While the 1SS133M is probably more *authentic*, a 1N4148 will probably just work as well. | +| D3, D4, D9, D10, D15, D16, D21, D22 | BAT43 Schottky Diode | 112-BAT43-TAPCT-ND | | +| D6, D12, D18, D24 | 1N5229B 4.3V 500mW Zener Diode | 1N5229BFSCT-ND | | +| R1, R10, R19, R28 | 1MΩ Resistor | 13-MFR-25FTE52-1MCT-ND | | +| R2, R11, R20, R29 | 4.7kΩ Resistor | 13-MFR-25FRF52-4K7CT-ND | | +| R3, R12, R21, R30 | 100kΩ Resistor | 13-MFR-25FRF52-100KCT-ND | | +| R4, R13, R22, R31 | 100Ω Resistor | 13-MFR-25FRF52-100RCT-ND | | +| R6, R15, R24, R33 | 5.1kΩ Resistor | 13-MFR-25FRF52-5K1CT-ND | | +| R7, R16, R25, R34 | 10kΩ Resistor | 13-MFR-25FRF52-10KCT-ND | +| R8, R17, R26, R35 | 1kΩ Resistor | 13-MFR-25FRF52-1KCT-ND | +| R9, R18, R27, R36 | 300Ω Resistor | MFR-25FRF52-300R | +| R37 | 10kΩ SMD Resistor | 2019-RK73H2ATTD1002FCT-ND | | +| J1, J2, J3, J4 | 2Pin S2B-PH-K-S Connector | 455-1719-ND | PHR-2 plus SPH-002T-P0.5L is the counterpart | +| J5 | 5Pin S5B-PH-K-S Connector | 455-1722-ND | PHR-5 plus SPH-002T-P0.5L is the counterpart | diff --git a/pcb/DonConIO/board.jpg b/pcb/DonConIO/board.jpg index 4296514..fe7c28c 100644 Binary files a/pcb/DonConIO/board.jpg and b/pcb/DonConIO/board.jpg differ