Contents
ESP32 PCB
Several different revisions of our PCB are in use by now. Here you can find information about the following revisions: 1.2, 1.3 and 1.5. For each revision, the respective section contains information about known bugs, pin layout, features, and more.
Revision 1.5
KiCAD and Gerber files are available in our hardware repository: Minimal Rev 1.5
Bugs
Currently, there are no known bugs.
Connections on the ESP32 PCB Rev 1.5
| Header | Pin Software | Pin PCB | Connection |
|---|---|---|---|
| HT_RL | PIN 2 | OUT | SSR Heating |
| T_SENS | PIN 16 | SIG | Temperature sensor |
| I2C | PIN 21 | SDA | Display and pressure sensor - Pin SDA |
| I2C | PIN 22 | SCL | Display and pressure sensor - Pin SCL |
| V_IN | - | 5V | Switching power supply (5 Volt) |
| PV_RL | PIN 17 | Valve | Relay 3-way-valve |
| PV_RL | PIN 27 | Pump | Relay pump |
| BPSW_SW | PIN 34 | BREW | Brew switch or optocoupler |
| BPSW_SW | PIN 39 | PWR | Power switch |
| BPSW_SW | PIN 35 | STEAM | Steam switch |
| BPSW_SW | PIN 39 | WATER | Hot water switch (not yet implemented) |
| S_LED | PIN 26 | OUT | Status or Temp LED |
| W_SENS | PIN 23 | SIG | Water level sensor |
| SCALE | PIN 25 | DAT2 | Scale DAT2 |
| SCALE | PIN 32 | DAT | Scale DAT |
| SCALE | PIN 33 | CLK | Scale CLK |
| GPIO | PIN 1 | IO01 | Reserved for later use, e.g. Brew switch LED |
| GPIO | PIN 3 | IO03 | Reserved for later use, e.g. Rotary encoder CLK |
| GPIO | PIN 4 | IO04 | Reserved for later use, e.g. Rotary encoder DT |
| GPIO | PIN 5 | IO05 | Reserved for later use, e.g. Rotary encoder SW |
| GPIO | PIN 21 | SDA | Reserved for later use, e.g. IO Expander |
| GPIO | PIN 22 | SCL | Reserved for later use, e.g. IO Expander |
| GPIO | PIN 12 | IO12 | JTAG Debugger TDI |
| GPIO | PIN 13 | IO13 | JTAG Debugger TCK |
| GPIO | PIN 14 | IO14 | JTAG Debugger TMS |
| GPIO | PIN 15 | IO15 | JTAG Debugger TDO |
| GPIO | PIN 18 | IO18 | Reserved for later use, e.g. Dimmer ZC |
| GPIO | PIN 19 | IO19 | Reserved for later use, e.g. Steam switch LED |
Placement and Function
All required parts and their function are listed here:
| Inscription PCB | Part | Function |
|---|---|---|
| C1 | Electrical capacitor 220 µF | Stabilization of power supply |
| C2 | Ceramic capacitor 100 nF | Stabilization of power supply |
| R1 | Resistor 220 Ω | Resistor TEMP_LED |
| R2 | Resistor 47 kΩ | Pull down steam switch |
| R3 | Resistor 47 kΩ | Pull down power switch |
| R4 | Resistor 4,7 kΩ | Pull up i2C |
| R5 | Resistor 4,7 kΩ | Pull up i2C |
| R6 | Resistor 47 kΩ | Pull down/up brew switch |
| R7 | Resistor 47 kΩ | Pull down hot water switch |
| JP1 | Solder jumper | Resistor bypass for LED when using WS1812 LED |
| JP2 | Solder jumper | Pull down or Pull up for brew switch or optocoupler |
Revision 1.3
KiCAD and Gerber files are available in our hardware repository: Minimal Rev 1.3
Bugs
Faulty optocoupler for brew detection:
- Only compatible with high level trigger optocoupler
- Workaround for low level trigger: Don’t solder pulldown resistor
R3, and depending on software version, set the following:- MASTER ->
OPTOCOUPLER_TYPEtoLOW - 3.3.0 and older ->
PINMODEVOLTAGESENSORtoINPUT_PULLUPandVOLTAGESENSORtoLOW
- MASTER ->
- Missing GPIO: IO03, IO04, IO05
Connections on the ESP32 PCB Rev 1.3
| Header | Pin Software | Pin PCB | Connection |
|---|---|---|---|
| HT_RL | PIN 2 | IO02 | SSR Heating |
| T_SENS | PIN 16 | IO16 | Temperature sensor |
| I2C | PIN 21 | SDA | Display and pressure sensor - PIN SDA |
| I2C | PIN 22 | SDL | Display and pressure sensor - PIN SCL |
| V_IN | - | V_IN | Switching power supply (5 Volt) |
| PV_RL | PIN 17 | Valve | Relay 3-way-valve |
| PV_RL | PIN 27 | Pump | Relay pump |
| B_SW | PIN 34 | IO34 | Brew switch or optocoupler |
| S_SW | PIN 35 | IO35 | Steam switch |
| P_SW | PIN 39 | IO39 | Power switch |
| E_TRIG | PIN 25 | IO25 | Trigger Silvia E CPU Up to s/w version 3.X, afterwards SCALE DAT2 |
| S_LED | PIN 26 | IO26 | Status or temp LED |
| W_SENS | PIN 23 | IO23 | Water level sensor |
| SCALE | PIN 32 | DAT | Scale DAT |
| SCALE | PIN 33 | CLK | Scale CLK |
| GPIO | PIN 1 | IO01 | Reserved for later use, e.g. Brew switch LED |
| GPIO | PIN 12 | IO12 | JTAG Debugger TDI |
| GPIO | PIN 13 | IO13 | JTAG Debugger TCK |
| GPIO | PIN 14 | IO14 | JTAG Debugger TMS |
| GPIO | PIN 15 | IO15 | JTAG Debugger TDO |
| GPIO | PIN 18 | IO18 | Reserved for later use, e.g. Dimmer ZC |
| GPIO | PIN 19 | IO19 | Reserved for later use, e.g. Steam switch LED |
| GPIO | PIN 36 | IO36 | Hot water switch (not yet implemented) |
Placement and Function
All required parts and their function are listed here:
| Inscription PCB | Part | Function |
|---|---|---|
| C1 | Electrical capacitor 220 µF | Stabilization of power supply |
| C2 | Ceramic capacitor 100 nF | Stabilization of power supply |
| R1 | Resistor 4,7 kΩ | Pull up i2C |
| R2 | Resistor 4,7 kΩ | Pull up i2C |
| R3 | Resistor 47 kΩ | Pull down brew switch |
| R4 | Resistor 47 kΩ | Pull down power switch |
| R5 | Resistor 47 kΩ | Pull down steam switch |
| R6 | Resistor 220 Ω | Resistor TEMP_LED |
| JP1 | Solder jumper | Resistor bypass for LED when using WS1812 LED |
Revision 1.2
KiCAD and Gerber files are available in our hardware repository: Minimal Rev 1.2
Bugs
Errors in PCB inscription: HEADER | PCB Inscription | Correct Inscription
-
S_LED VCC 5V E_TRIG VCC 5V W_SENS IO36 IO23 GPIO IO23 IO36
Faulty optocoupler for brew detection:
- Only compatible with high level trigger optocoupler
- Workaround for low level trigger: Don’t solder pulldown resistor
R3, and depending on software version, set the following:- MASTER ->
OPTOCOUPLER_TYPEtoLOW - 3.3.0 and older ->
PINMODEVOLTAGESENSORtoINPUT_PULLUPandVOLTAGESENSORtoLOW
- MASTER ->
- Missing GPIO: IO03, IO04, IO05
Connectors of the ESP32 PCB Rev 1.2
| Header | PIN Software | PIN PCB | Connection |
|---|---|---|---|
| HT_RL | PIN 2 | IO02 | SSR Heating |
| T_SENS | PIN 16 | IO16 | Temperature sensor |
| I2C | PIN 21 | SDA | Display and pressure sensor - PIN SDA |
| I2C | PIN 22 | SDL | Display and pressure sensor - PIN SCL |
| V_IN | - | V_IN | Switching power supply (5 Volt) |
| PV_RL | PIN 17 | Valve | Relay 3-way-valve |
| PV_RL | PIN 27 | Pump | Relay pump |
| B_SW | PIN 34 | IO34 | Brew switch or optocoupler |
| S_SW | PIN 35 | IO35 | Steam switch |
| P_SW | PIN 39 | IO39 | Power switch |
| E_TRIG | PIN 25 | IO25 | Trigger Silvia E CPU Up to s/w version 3.X, afterwards SCALE DAT2 |
| S_LED | PIN 26 | IO26 | Status or temp LED |
| W_SENS | PIN 23 | IO23 | Water level sensor |
| SCALE | PIN 32 | DAT | Scale DAT |
| SCALE | PIN 33 | CLK | Scale CLK |
| GPIO | PIN 1 | IO01 | Reserved for later use, e.g. Brew switch LED |
| GPIO | PIN 12 | IO12 | JTAG Debugger TDI |
| GPIO | PIN 13 | IO13 | JTAG Debugger TCK |
| GPIO | PIN 14 | IO14 | JTAG Debugger TMS |
| GPIO | PIN 15 | IO15 | JTAG Debugger TDO |
| GPIO | PIN 18 | IO18 | Reserved for later use, e.g. Dimmer ZC |
| GPIO | PIN 19 | IO19 | Reserved for later use, e.g. Steam switch LED |
| GPIO | PIN 36 | IO36 | Hot water switch (not yet implemented) |
Placement and Function
All required parts and their function are listed here:
| Inscription PCB | Part | Function |
|---|---|---|
| C1 | Electrical capacitor 220 µF | Stabilization of power supply |
| C2 | Ceramic capacitor 100 nF | Stabilization of power supply |
| R1 | Resistor 4,7 kΩ | Pull up i2C |
| R2 | Resistor 4,7 kΩ | Pull up i2C |
| R3 | Resistor 47 kΩ | Pull down brew switch |
| R4 | Resistor 47 kΩ | Pull down power switch |
| R5 | Resistor 47 kΩ | Pull down steam switch |
| R6 | Resistor 220 Ω | Resistor TEMP_LED |
| JP1 | Solder jumper | Resistor bypass for LED when using WS1812 LED |