# Dimmer ## Description Single-channel 12-24V LED strip dimmer with ESP32-WROOM BLE control, hall pairing input, red status LED, and safe-fail 220VAC protection strategy ## Project Details - **Owner:** serzhu - **Created:** 3/22/2026 - **Last Updated:** 3/22/2026 - **Visibility:** Public - **System Architecture:** ```mermaid flowchart TD PWR_IN[Power Input 12-24V] --> PROT_IN[Input Protection and Fuse] PROT_IN --> HV_GUARD[AC Fault Clamp and Safe Failure Path] HV_GUARD --> BUCK[12-24V to 3.3V Regulator] HV_GUARD --> LOAD_PATH[High Current LED Power Path] ESP[ESP32 WROOM BLE Module] --> GATE_DRV[Gate Driver] GATE_DRV --> MOSFET[Low Side PWM MOSFET] LOAD_PATH --> LED_OUT[LED Strip Output] MOSFET --> LED_OUT BUCK --> ESP BUCK --> HALL[Hall Sensor Pairing Input] BUCK --> STAT_LED[Red Status LED] HALL --> ESP ESP --> STAT_LED LED_OUT --> PROT_OUT[Output Fault Protection] PROT_OUT --> SAFE_FAIL[Safe Failure Against 220V AC] PWR_IN --> GND_SYS[System Ground] BUCK --> GND_SYS ESP --> GND_SYS MOSFET --> GND_SYS ``` ## Key Components ### D1 — [SMBJ24CA-TR](https://www.flux.ai/lcsc/smbj24ca-tr.md) - JLCPCB Part Class: Extended Part - Manufacturer Part Number: SMBJ24CA-TR - Role: Surge Clamp - Manufacturer Name: ST(意法半导体) - Package or Case Code: SMB_L4.6-W3.6-LS5.3-BI - Role Details: Bidirectional TVS across protected input rail for surge and accidental AC fault clamping - Product Info Url: https://lcsc.com/product-detail/TVS_STMicroelectronics_SMBJ24CA-TR_SMBJ24CA-TR_C133667.html - Part Type: TVS - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2304140030_STMicroelectronics-SMBJ24CA-TR_C133667.pdf - LCSC Part Number: C133667 - Package: SMB_L4.6-W3.6-LS5.3-BI **Pins:** - 1 [pin 1] - 2 [pin 2] ### D2 — [LTST-C190KRKT](https://www.flux.ai/adrian95/ltst-c190krkt.md) - Part Type: LED - Manufacturer Name: Lite-On Inc. - Role Details: Red SMD operation indicator controlled by ESP32 - Forward Voltage: 2V - Manufacturer Part Number: LTST-C190KRKT - License: https://creativecommons.org/licenses/by/4.0/ - Role: Indicator - Datasheet URL: https://optoelectronics.liteon.com/upload/download/DS-22-99-0151/LTST-C190KRKT.pdf - Package: 0603 **Pins:** - A [pin 2] - K [pin 1] ### D3 — [BZT52C12](https://www.flux.ai/lcsc/bzt52c12.md) - Product Info Url: https://lcsc.com/product-detail/Others_SK-BZT52C12_C216721.html - LCSC Part Number: C216721 - Diode Type: Zener Diodes - Package or Case Code: SOD-123_L2.6-W1.6-LS3.5-RD - Package: SOD-123_L2.6-W1.6-LS3.5-RD - Part Type: Zener Diodes - Manufacturer Part Number: BZT52C12 - Role: Supply Clamp - Forward Voltage: 0.9V to 1.2V - Role Details: 12 V zener clamp for gate-driver VDD rail - Manufacturer Name: SHIKUES(时科) - Max Reverse Voltage: 12V - JLCPCB Part Class: Extended Part - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2304140030_Shikues-BZT52C12_C216721.pdf **Pins:** - 1 [pin 1] - 2 [pin 2] ### D4 — [SMBJ24CA-TR](https://www.flux.ai/lcsc/smbj24ca-tr.md) - Package: SMB_L4.6-W3.6-LS5.3-BI - Manufacturer Name: ST(意法半导体) - JLCPCB Part Class: Extended Part - Manufacturer Part Number: SMBJ24CA-TR - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2304140030_STMicroelectronics-SMBJ24CA-TR_C133667.pdf - Part Type: TVS - Role: Output Surge Clamp - LCSC Part Number: C133667 - Package or Case Code: SMB_L4.6-W3.6-LS5.3-BI - Role Details: Bidirectional TVS across LED output pair for safe-fail AC fault clamping - Product Info Url: https://lcsc.com/product-detail/TVS_STMicroelectronics_SMBJ24CA-TR_SMBJ24CA-TR_C133667.html **Pins:** - 1 [pin 1] - 2 [pin 2] ### F1 — [0ZCF0200FF2C](https://www.flux.ai/lcsc/0zcf0200ff2c.md) - Role: Input Protection - JLCPCB Part Class: Extended Part - Package or Case Code: F2920 - Manufacturer Name: belfuse - Package: F2920 - Manufacturer Part Number: 0ZCF0200FF2C - LCSC Part Number: C3762403 - Role Details: High-current resettable fuse in series with VIN+ for fault energy limiting **Pins:** - 1 [pin 1] - 2 [pin 2] ### F2 — [0ZCF0200FF2C](https://www.flux.ai/lcsc/0zcf0200ff2c.md) - Package: F2920 - Role: Output Protection - Voltage Rating: 24V - Manufacturer Name: belfuse - Current Rating: 20A - JLCPCB Part Class: Extended Part - LCSC Part Number: C3762403 - Role Details: High-current resettable fuse in series with LED+ for fault energy limiting - Manufacturer Part Number: 0ZCF0200FF2C - Package or Case Code: F2920 **Pins:** - 1 [pin 1] - 2 [pin 2] ### Q1 — [HYG090ND06LS1C2](https://www.flux.ai/lcsc/hyg090nd06ls1c2.md) - LCSC Part Number: C2999758 - JLCPCB Part Class: Extended Part - Drain to Source Voltage: 60V - Continuous Drain Current: 56A - Package: PDFN-8_L5.9-W5.2-P1.27-LS6.2-BL-1 - Role Details: 60 V low-side N-channel MOSFET for LED strip dimming with surge margin over 24 V bus - Package or Case Code: PDFN-8_L5.9-W5.2-P1.27-LS6.2-BL-1 - Manufacturer Name: HUAYI(华羿微) - Operating Temperature: -55 ~ +175℃ - Datasheet URL: https://storage.googleapis.com/graviton-electric-symbols/document_assets/lcsc/2204251600_HUAYI-HYG090ND06LS1C2_C2999758.pdf - Transistor Type: 2 N-Channel - Role: Power Switch - Part Type: MOSFETs - Manufacturer Part Number: HYG090ND06LS1C2 - Power: 60W **Pins:** - D1 [pin 7] - D1 [pin 8] - D2 [pin 5] - D2 [pin 6] - G1 [pin 2] - G2 [pin 4] - S1 [pin 1] - S2 [pin 3] ### RV1 — [MOV-10D471KTR](https://www.flux.ai/adrian95/mov-10d471ktr.md) - Datasheet URL: https://www.bourns.com/docs/Product-Datasheets/MOV10D.pdf - Voltage: 470V - Role Details: MOV across input to force safe failure during accidental 220V AC application - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: MOV-10D471K - Part Type: Varistor - Role: Protection - Package: Disc 10mm - Manufacturer Name: Bourns Inc. **Pins:** - 1 [pin 1] - 2 [pin 2] ### RV2 — [MOV-10D471KTR](https://www.flux.ai/adrian95/mov-10d471ktr.md) - Part Type: Varistor - Voltage: 470V - Package: Disc 10mm - Role Details: MOV across output to force safe failure during accidental 220V AC application - Manufacturer Name: Bourns Inc. - Datasheet URL: https://www.bourns.com/docs/Product-Datasheets/MOV10D.pdf - License: https://creativecommons.org/licenses/by/4.0/ - Role: Protection - Manufacturer Part Number: MOV-10D471K **Pins:** - 1 [pin 1] - 2 [pin 2] ### U1 — [ESP32-WROOM-32](https://www.flux.ai/vasyl/esp32-wroom-32.md) - Manufacturer Name: Espressif Systems - Software: BLE brightness control and pairing mode firmware - Operating Voltage: 3.3V - Role Details: ESP32 BLE controller for brightness control and pairing mode - Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32_datasheet_en.pdf - Part Type: RF module - Manufacturer Part Number: ESP32-WROOM-32 - Role: Controller - Package: Module **Pins:** - EN [pin 3] - GND [pin 38] - GND [pin 39] - GND [pin 1] - GND [pin 15] - IO0 [pin 25] - IO12 [pin 14] - IO13 [pin 16] - IO14 [pin 13] - 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 10] - IO26 [pin 11] - IO27 [pin 12] - IO32 [pin 8] - IO33 [pin 9] - IO34 [pin 6] - IO35 [pin 7] - IO4 [pin 26] - IO5 [pin 29] - NC [pin 32] - RXD0/IO3 [pin 34] - SCK/CLK [pin 20] - SCS/CMD [pin 19] - SDI/SD1 [pin 22] - SDO/SD0 [pin 21] - SENSOR_VN [pin 5] - SENSOR_VP [pin 4] - SHD/SD2 [pin 17] - SWP/SD3 [pin 18] - TXD0/IO1 [pin 35] - VDD [pin 2] ### U2 — [TPS54302](https://www.flux.ai/kicad-part-library/tps54302.md) - Datasheet URL: http://www.ti.com/lit/ds/symlink/tps54302.pdf - Output Voltage: 3.3V - Role: Power Supply - Manufacturer Name: Texas Instruments - Package: SOT-23-6 - Role Details: Main buck regulator generating 3.3V for ESP32 and low voltage logic - Manufacturer Part Number: TPS54302 - Package or Case Code: SOT-23-6 **Pins:** - BOOT [pin 6] - EN [pin 5] - FB [pin 4] - GND [pin 1] - SW [pin 2] - VIN [pin 3] ### U3 — [DRV5032FADBZR](https://www.flux.ai/adrian95/drv5032fadbzr.md) - Manufacturer Name: Texas Instruments - Datasheet URL: https://www.ti.com/general/docs/suppproductinfo.tsp?distId=10&gotoUrl=https%3A%2F%2Fwww.ti.com%2Flit%2Fgpn%2Fdrv5032 - Operating Voltage: 3.3V - Package: SOT-23-3 - License: https://creativecommons.org/licenses/by/4.0/ - Role: Sensor - Part Type: Sensor - Role Details: Hall sensor used as non-contact pairing button input - Manufacturer Part Number: DRV5032FADBZR **Pins:** - GND [pin 2] - OUTPUT [pin 3] - VDD [pin 1] ### U4 — [UCC27511ADBVR](https://www.flux.ai/lcsc/ucc27511adbvr.md) - Package: SOT-23-6_L2.9-W1.6-P0.95-LS2.9-BL - LCSC Part Number: C2676982 - Operating Voltage: 12V - Role: Gate Driver - Manufacturer Name: TI(德州仪器) - Manufacturer Part Number: UCC27511ADBVR - JLCPCB Part Class: Extended Part - Package or Case Code: SOT-23-6_L2.9-W1.6-P0.95-LS2.9-BL - Role Details: Low-side MOSFET gate driver for PWM dimming, supplied from protected/clamped 12 V rail **Pins:** - GND [pin 4] - IN– [pin 5] - IN+ [pin 6] - OUTH [pin 2] - OUTL [pin 3] - VDD [pin 1] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/serzhu/dimmer](https://www.flux.ai/serzhu/dimmer).* --- *Generated from [https://www.flux.ai/serzhu/dimmer](https://www.flux.ai/serzhu/dimmer)*