# 12-24 -> esp controller
## Description
Welcome to your new project. Imagine what you can build here.
## Project Details
- **Owner:** mrgigio
- **Created:** 4/17/2026
- **Last Updated:** 4/17/2026
- **Visibility:** Public
## Key Components
### D1 — [1N4007RLG](https://www.flux.ai/jecstronic/1n4007rlg~07j.md)
- Role Details: Flyback diode for relay coil
- Role: Protection
- Datasheet URL: https://www.onsemi.com/pdf/datasheet/1n4001-d.pdf
- Manufacturer Name: onsemi
- Part Type: Diode
- Manufacturer Part Number: 1N4007RLG
- Package: DO-41
- License: https://creativecommons.org/licenses/by/4.0/
**Pins:**
- anode [pin 2]
- cathode [pin 1]
### D2 — [SS14](https://www.flux.ai/jecstronic/ss14~ri4.md)
- Role Details: Prevents harmful back-power interaction between rails while allowing simple prototype power OR-ing
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Name: Slkor(SLKORMICRO Elec.)
- Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_Slkor-SLKORMICRO-Elec--SS14_C444721.pdf
- Package: SMA
- Part Type: Diode
- Manufacturer Part Number: SS14
- Role: Schottky Diode
**Pins:**
- Anode [pin A]
- Cathode [pin C]
### J1 — [2-Position Screw Terminal](https://www.flux.ai/corynrobinson/2-position-screw-terminal~s4.md)
- Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf
- Package: Through Hole
- Role Details: 12V-24V DC power input for buck converter and system power
- Role: Power Connector
- Manufacturer Part Number: 691137710002
- Manufacturer Name: Würth Elektrik
- Part Type: Connector
**Pins:**
- P1 [pin 1]
- P2 [pin 2]
### K1 — [SRD-05VDC-SL-C](https://www.flux.ai/vasy_skral/srd-05vdc-sl-c~go1.md)
- Role Details: SPDT relay used with COM and NO exported as dry contact; NC intentionally unused
- Manufacturer Part Number: SRD-05VDC-SL-C
- Manufacturer Name: Ningbo Songle Relay
- Role: Relay
- Part Type: Relay
- Datasheet URL: https://www.circuitbasics.com/wp-content/uploads/2015/11/SRD-05VDC-SL-C-Datasheet.pdf
- Package: Through Hole
**Pins:**
- A1 [pin A1]
- A2 [pin A2]
- COM [pin COM]
- NC [pin NC]
- NO [pin NO]
### Q1 — [2N2222](https://www.flux.ai/adrian95/2n2222~l5y.md)
- Manufacturer Part Number: 2N2222
- Manufacturer Name: Solid State Inc.
- License: https://creativecommons.org/licenses/by/4.0/
- Role Details: NPN low-side switch for relay coil
- Datasheet URL: http://www.solidstateinc.us/specsearch/specs/2N2221A-ssi.pdf
- Role: Relay Driver
- Package: TO-92
- Part Type: Transistor
**Pins:**
- B [pin 2]
- C [pin 3]
- E [pin 1]
### RELAY_OUT — [2-Position Screw Terminal](https://www.flux.ai/corynrobinson/2-position-screw-terminal~s4.md)
- Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf
- Role Details: Dry contact output for external coin pulse input
- Package: Through Hole
- Role: Output Connector
- Manufacturer Part Number: 691137710002
- Part Type: Connector
- Manufacturer Name: Würth Elektrik
**Pins:**
- P1 [pin 1]
- P2 [pin 2]
### U1 — [LM2596S-5.0/NOPB](https://www.flux.ai/adrian95/lm2596s-5p0nopb~ji8.md)
- Role Details: Generates regulated 5V from 12V-24V machine input
- Implementation Details: Tie ON/OFF active, use fixed 5V output with local bulk and bypass capacitors. Prototype-grade buck stage pending inductor verification against datasheet or chosen module strategy.
- Part Type: Integrated Circuit
- Manufacturer Part Number: LM2596S-5.0/NOPB
- Datasheet URL: https://www.ti.com/lit/ds/symlink/lm2596.pdf
- Role: Buck Converter
- Manufacturer Name: Texas Instruments
- License: https://creativecommons.org/licenses/by/4.0/
- Package: TO-263-6
**Pins:**
- ~ON~/OFF [pin 5]
- FEEDBACK [pin 4]
- GND_TAB [pin 6]
- GROUND [pin 3]
- OUTPUT [pin 2]
- VIN [pin 1]
### U2 — [ESP32-DEVKITC](https://www.flux.ai/vasy_skral/esp32-devkitc~7mc.md)
- Manufacturer Part Number: ESP32-DEVKITC
- Datasheet URL: http://espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf
- Manufacturer Name: Espressif Systems
- Part Type: Development Boards
- Role: Controller
- Role Details: ESP32-WROOM-32 based 38-pin development board with onboard USB, mounted via 2x19 headers on the carrier PCB; pin usage preserved for relay control on GPIO23 and INA219 I2C on GPIO21/GPIO22.
- Package: Through Hole
- License: https://creativecommons.org/licenses/by/4.0/
- Symbol Style: Parametric
**Pins:**
- 3V3 [pin 1]
- CLK [pin 20]
- CMD [pin 18]
- EN [pin 2]
- EXT_5V [pin 19]
- GND1 [pin 14]
- GND2 [pin 32]
- GND3 [pin 38]
- IO0 [pin 25]
- IO12 [pin 13]
- IO13 [pin 15]
- IO14 [pin 12]
- IO15 [pin 23]
- IO16 [pin 27]
- IO17 [pin 28]
- IO18 [pin 30]
- IO19 [pin 31]
- IO2 [pin 24]
- IO21 [pin 33]
- IO22 [pin 36]
- IO23 [pin 37]
- IO25 [pin 9]
- IO26 [pin 10]
- IO27 [pin 11]
- IO32 [pin 7]
- IO33 [pin 8]
- IO34 [pin 5]
- IO35 [pin 6]
- IO4 [pin 26]
- IO5 [pin 29]
- RXD0 [pin 34]
- SD0 [pin 21]
- SD1 [pin 22]
- SD2 [pin 16]
- SD3 [pin 17]
- SENSOR_VN [pin 4]
- SENSOR_VP [pin 3]
- TXD0 [pin 35]
### U6 — [INA219AIDCNT](https://www.flux.ai/vasy_skral/ina219aidcnt~q48.md)
- Role Details: High-side current monitor inserted between 5V rail and relay coil; I2C telemetry to ESP32 for relay activation detection
- Manufacturer Part Number: INA219AIDCNT
- Datasheet URL: https://www.ti.com/lit/ds/symlink/ina219.pdf
- Package: SOT-23-8
- Part Type: Integrated Circuit
- Manufacturer Name: Texas Instruments
- Role: Current Sensor
**Pins:**
- A0 [pin 7]
- A1 [pin 8]
- GND [pin 3]
- IN- [pin 2]
- IN+ [pin 1]
- SCL [pin 5]
- SDA [pin 6]
- VS [pin 4]
*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/mrgigio/12-24-greater-esp-controller~ya](https://www.flux.ai/mrgigio/12-24-greater-esp-controller~ya).*
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*Generated from [https://www.flux.ai/mrgigio/12-24-greater-esp-controller~ya](https://www.flux.ai/mrgigio/12-24-greater-esp-controller~ya)*