# 12-24 -> esp controller ## Description Golf ball dispenser controller with protected 12V-24V DC input, LM2596 5V buck, ESP32 control, INA219 relay-coil sensing, and dry-contact relay output. ## Project Details - **Owner:** edd03 - **Created:** 4/17/2026 - **Last Updated:** 4/21/2026 - **Visibility:** Public - **Forks:** 1 ## Key Components ### D1 — [1N4007RLG](https://www.flux.ai/jecstronic/1n4007rlg.md) - License: https://creativecommons.org/licenses/by/4.0/ - Package: DO-41 - Part Type: Diode - Role Details: Flyback diode for relay coil - Manufacturer Name: onsemi - Datasheet URL: https://www.onsemi.com/pdf/datasheet/1n4001-d.pdf - Role: Protection - Manufacturer Part Number: 1N4007RLG **Pins:** - anode [pin 2] - cathode [pin 1] ### D2 — [SS14](https://www.flux.ai/jecstronic/ss14.md) - Manufacturer Name: Slkor(SLKORMICRO Elec.) - Package: SMA - Role Details: Prevents harmful back-power interaction between rails while allowing simple prototype power OR-ing - Part Type: Diode - Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_Slkor-SLKORMICRO-Elec--SS14_C444721.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Role: Schottky Diode - Manufacturer Part Number: SS14 **Pins:** - Anode [pin A] - Cathode [pin C] ### D3 — [SMBJ26A-TR](https://www.flux.ai/lcsc/smbj26a-tr.md) - Role Details: Unidirectional TVS diode from protected VIN to ground for 24V nominal industrial cable surge suppression - Role: TVS Protection - LCSC Part Number: C133666 - JLCPCB Part Class: Extended Part - Package or Case Code: SMB_L4.6-W3.6-LS5.3-RD - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2304140030_STMicroelectronics-SMBJ26A-TR_C133666.pdf - Manufacturer Part Number: SMBJ26A-TR - Package: DO-214AA - Part Type: TVS - Product Info Url: https://lcsc.com/product-detail/TVS_STMicroelectronics_SMBJ26A-TR_SMBJ26A-TR_C133666.html - Manufacturer Name: ST(意法半导体) **Pins:** - A [pin 2] - K [pin 1] ### D6 — [BZT52C15-7-F](https://www.flux.ai/adrian95/bzt52c15-7-f.md) - Role Details: 15V zener between Q3 gate and source to keep PMOS VGS within safe limits - Datasheet URL: https://www.diodes.com/assets/Datasheets/ds18004.pdf - Manufacturer Name: Diodes Incorporated - Part Type: Diode - License: https://creativecommons.org/licenses/by/4.0/ - Role: Gate Clamp - Manufacturer Part Number: BZT52C15-7-F - Package: SOD-123 **Pins:** - A [pin 2] - K [pin 1] ### F2 — [1206L100/33NR](https://www.flux.ai/adrian95/1206l10033nr.md) - Part Type: Fuse - Datasheet URL: https://www.lcsc.com/datasheet/C22435907.pdf - Current Rating: 1A - Role Details: Resettable PPTC polyfuse in series with VIN_RAW to limit sustained fault current on external cable input - Role: Input Protection Fuse - Manufacturer Name: LUTE - Manufacturer Part Number: 1206L100/33NR - Package: 1206 - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - P1 [pin 1] - P2 [pin 2] ### FB2 — [MPZ1005S121HT000](https://www.flux.ai/jecstronic/mpz1005s121ht000.md) - Part Type: Filter - Manufacturer Name: TDK Corporation - Package: 0402 - Role Details: Ferrite bead between protected VIN reservoir and LM2596 VIN to attenuate high-frequency conducted noise - Role: EMI Filter - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: MPZ1005S121HT000 - Datasheet URL: https://product.tdk.com/en/system/files?file=dam/doc/product/emc/emc/beads/catalog/beads_commercial_power_mpz1005-h_en.pdf **Pins:** - 1 [pin 1] - 2 [pin 2] ### J1 — [2-Position Screw Terminal](https://www.flux.ai/corynrobinson/2-position-screw-terminal.md) - Package: Through Hole - Manufacturer Name: Würth Elektrik - Part Type: Connector - Role Details: 12V-24V DC power input for buck converter and system power - Manufacturer Part Number: 691137710002 - Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf - Role: Power Connector **Pins:** - P1 [pin 1] - P2 [pin 2] ### K1 — [SRD-05VDC-SL-C](https://www.flux.ai/vasy_skral/srd-05vdc-sl-c.md) - Role Details: SPDT relay used with COM and NO exported as dry contact; NC intentionally unused - Manufacturer Part Number: SRD-05VDC-SL-C - Part Type: Relay - Manufacturer Name: Ningbo Songle Relay - Datasheet URL: https://www.circuitbasics.com/wp-content/uploads/2015/11/SRD-05VDC-SL-C-Datasheet.pdf - Package: Through Hole - Role: Relay **Pins:** - A1 [pin A1] - A2 [pin A2] - COM [pin COM] - NC [pin NC] - NO [pin NO] ### Q1 — [PN2222A](https://www.flux.ai/kicad-part-library/pn2222a.md) - Role Details: NPN low-side switch for relay coil, driven from ESP32 GPIO23 through R1 with R2 pull-down - Datasheet URL: https://www.onsemi.com/pub/Collateral/PN2222-D.PDF - Package or Case Code: TO-92_Inline - Package: TO-92 - Role: Relay Driver - Manufacturer Part Number: PN2222A **Pins:** - B [pin 2] - C [pin 3] - E [pin 1] ### Q2 — [DMPH6250SQ-7](https://www.flux.ai/adrian95/dmph6250sq-7.md) - Part Type: Transistor - Role: Reverse Protection - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: DMPH6250SQ-7 - Manufacturer Name: Diodes Incorporated - Package: SOT-23-3 - Role Details: High-side P-channel MOSFET used as ideal-diode style reverse polarity protection between fused input and protected VIN rail - Datasheet URL: https://www.diodes.com/assets/Datasheets/DMPH6250SQ.pdf **Pins:** - D [pin 3] - G [pin 1] - S [pin 2] ### RELAY_OUT — [2-Position Screw Terminal](https://www.flux.ai/corynrobinson/2-position-screw-terminal.md) - Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf - Manufacturer Part Number: 691137710002 - Role Details: Dry contact output for external coin pulse input - Package: Through Hole - Part Type: Connector - Role: Output Connector - Manufacturer Name: Würth Elektrik **Pins:** - P1 [pin 1] - P2 [pin 2] ### U1 — [LM2596S-5.0/NOPB](https://www.flux.ai/adrian95/lm2596s-5p0nopb.md) - Manufacturer Name: Texas Instruments - Part Type: Integrated Circuit - 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. - Role Details: Generates regulated 5V from 12V-24V machine input - Datasheet URL: https://www.ti.com/lit/ds/symlink/lm2596.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Role: Buck Converter - Manufacturer Part Number: LM2596S-5.0/NOPB - 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.md) - Role: Controller - Datasheet URL: http://espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf - Part Type: Development Boards - Manufacturer Part Number: ESP32-DEVKITC - 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. - License: https://creativecommons.org/licenses/by/4.0/ - Package: Through Hole - Symbol Style: Parametric - Manufacturer Name: Espressif Systems **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.md) - Role Details: High-side current monitor inserted between 5V rail and relay coil; I2C telemetry to ESP32 for relay activation detection - Package: SOT-23-8 - Symbol Style: parametric-v1 - Manufacturer Name: Texas Instruments - Part Type: Integrated Circuit - Role: Current Sensor - Datasheet URL: https://www.ti.com/lit/ds/symlink/ina219.pdf - Manufacturer Part Number: INA219AIDCNT **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/edd03/12-24-greater-esp-controller](https://www.flux.ai/edd03/12-24-greater-esp-controller).* --- *Generated from [https://www.flux.ai/edd03/12-24-greater-esp-controller](https://www.flux.ai/edd03/12-24-greater-esp-controller)*