# ESP32 Heater Controller
## Description
ESP32-based USB-C powered controller for four 5 V / 1 W heater strips, with PCB-mounted safety and ambient temperature sensing, OLED UI, rotary encoder, RGB status LED, and cost-conscious reliability/protection design.
## Project Details
- **Owner:** roboticsnerd
- **Created:** 7/13/2026
- **Last Updated:** 7/13/2026
- **Visibility:** Public
## Key Components
### D1 — [SMF5.0A](https://www.flux.ai/lcsc/smf5p0a~bz6b.md)
- Part Type: TVS
- Allow Substitutes: Yes - equivalent 5V unidirectional TVS after clamp/leakage/package review
- Package or Case Code: SOD-123FL_L2.8-W1.8-LS3.6-RD
- Role: Protection
- Datasheet URL: https://www.lcsc.com/datasheet/C2990427.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=T1kIXgFeT1NaU1RXQFBbUlUHT1cKU1NXFVBeX1VSTlAxVlNRTlBbUVFXRldaXzsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D
- Max Reverse Voltage: 5V
- Diode Type: Schottky Diode
- JLCPCB Part Class: Extended Part
- Forward Voltage: 0.45V to 0.55V (at 1A)V
- LCSC Part Number: C2990427
- Manufacturer Name: Liown(里阳半导体)
- Role Details: 5V VBUS TVS diode for USB input transient protection
- Manufacturer Part Number: SMF5.0A
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### D2 — [KT-0603R](https://www.flux.ai/adrian95/kt-0603r~7c.md)
- Role: Current Limiting
- License: https://creativecommons.org/licenses/by/4.0/
- Part Type: LED
- Manufacturer Part Number: KT-0603R
- Manufacturer Name: Hubei KENTO Elec
- Allow Substitutes: Yes
- Datasheet URL: https://www.lcsc.com/datasheet/lcsc_datasheet_1810231112_Hubei-KENTO-Elec-KT-0603R_C2286.pdf
- Role Details: Red discrete status LED; grouped with D3/D4 to provide RGB indication without faulty RGB LED footprint
**Pins:**
- A [pin 2]
- K [pin 1]
### D3 — [P0603P1N46G12](https://www.flux.ai/rohit297/p0603p1n46g12~4e.md)
- Manufacturer Part Number: P0603P1N46G12
- Part Type: LED
- Manufacturer Name: Silverlight
- Role Details: Green discrete status LED; grouped with D2/D4 to provide RGB indication
- Datasheet URL: https://wmsc.lcsc.com/wmsc/upload/file/pdf/v2/lcsc/2208181800_Silverlight-P0603P1N46G12_C5123548.pdf
- Forward Voltage: 2V
- Allow Substitutes: Yes
- Role: Current Limiting
- Package or Case Code: D_0603_1608Metric
**Pins:**
- A [pin 2]
- K [pin 1]
### D4 — [KT-0603B](https://www.flux.ai/adrian95/kt-0603b~oob.md)
- Part Type: LED
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Current Limiting
- Datasheet URL: https://www.lcsc.com/datasheet/C2288.pdf
- Manufacturer Part Number: KT-0603B
- Manufacturer Name: Hubei KENTO Elec
- Allow Substitutes: Yes
- Role Details: Blue discrete status LED; grouped with D2/D3 to provide RGB indication
- LCSC Part Number: C2288
**Pins:**
- A [pin 2]
- K [pin 1]
### J1 — [USB4215-03-A](https://www.flux.ai/adrian95/usb4215-03-a~kg3.md)
- Datasheet URL: https://gct.co/files/specs/usb4215-spec.pdf
- Symbol Style: parametric-v1
- Allow Substitutes: Yes - compatible USB2 Type-C receptacles with same footprint after mechanical review
- Role Details: USB-C receptacle, USB2 data plus VBUS/CC for sink operation
- Part Type: USB C
- Manufacturer Part Number: USB4215-03-A
- Package or Case Code: GCT_USB4215-03-A_REVA
- Role: Connector
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Name: GCT
**Pins:**
- CC1 [pin A5]
- CC2 [pin B5]
- DN1 [pin A7]
- DN2 [pin B7]
- DP1 [pin A6]
- DP2 [pin B6]
- GND_A [pin A1_B12]
- GND_B [pin B1_A12]
- SBU1 [pin A8]
- SBU2 [pin B8]
- SHIELD [pin SH1]
- SHIELD [pin SH4]
- SHIELD [pin SH2]
- SHIELD [pin SH3]
- VBUS_A [pin A4_B9]
- VBUS_B [pin B4_A9]
### J2 — [691137710002](https://www.flux.ai/adrian95/691137710002~c39.md)
- Manufacturer Name: Würth Elektronik
- License: https://creativecommons.org/licenses/by/4.0/
- Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf
- Allow Substitutes: Yes - compatible rated 2-position 3.5mm screw terminal after mechanical review
- Role: Heater Connector
- Manufacturer Part Number: 691137710002
- Role Details: 2-position green screw terminal for 5V heater channel 1
- Part Type: Connector
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### J3 — [691137710002](https://www.flux.ai/adrian95/691137710002~c39.md)
- License: https://creativecommons.org/licenses/by/4.0/
- Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf
- Manufacturer Name: Würth Elektronik
- Manufacturer Part Number: 691137710002
- Part Type: Connector
- Role: Heater Connector
- Allow Substitutes: Yes - compatible rated 2-position 3.5mm screw terminal after mechanical review
- Role Details: 2-position green screw terminal for 5V heater channel 2
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### J4 — [691137710002](https://www.flux.ai/adrian95/691137710002~c39.md)
- License: https://creativecommons.org/licenses/by/4.0/
- Allow Substitutes: Yes - compatible rated 2-position 3.5mm screw terminal after mechanical review
- Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf
- Manufacturer Name: Würth Elektronik
- Manufacturer Part Number: 691137710002
- Role: Heater Connector
- Part Type: Connector
- Role Details: 2-position green screw terminal for 5V heater channel 3
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### J5 — [691137710002](https://www.flux.ai/adrian95/691137710002~c39.md)
- Manufacturer Part Number: 691137710002
- Allow Substitutes: Yes - compatible rated 2-position 3.5mm screw terminal after mechanical review
- Part Type: Connector
- Role Details: 2-position green screw terminal for 5V heater channel 4
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Heater Connector
- Datasheet URL: https://www.we-online.com/katalog/datasheet/691137710002.pdf
- Manufacturer Name: Würth Elektronik
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### J7 — [TSW-104-07-G-S](https://www.flux.ai/adrian95/tsw-104-07-g-s~983.md)
- License: https://creativecommons.org/licenses/by/4.0/
- Datasheet URL: http://suddendocs.samtec.com/prints/tsw-xxx-xx-xxx-x-xx-xxx-mkt.pdf
- Role: Connector
- Role Details: 1x4 UART debug header: 3V3, GND, TXD0, RXD0
- Part Type: Connector
- Allow Substitutes: Yes
- Manufacturer Part Number: TSW-104-07-G-S
- Package or Case Code: TSW10407GS
- Manufacturer Name: Samtec Inc.
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
- 3 [pin 3]
- 4 [pin 4]
### Q1 — [SI2302](https://www.flux.ai/jecstronic/si2302~47t.md)
- Role: Heater MOSFET
- Manufacturer Name: BORN
- Role Details: Overspecified low-side N-MOSFET for 5V/200mA heater PWM channel 1
- Allow Substitutes: Yes - logic-level N-MOSFET with low RDS(on) at 3.3V gate after footprint review
- Manufacturer Part Number: SI2302
- Part Type: Transistor
- Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_BORN-SI2302_C344009.pdf
**Pins:**
- D
- G
- S
### Q2 — [SI2302](https://www.flux.ai/jecstronic/si2302~47t.md)
- Allow Substitutes: Yes - logic-level N-MOSFET with low RDS(on) at 3.3V gate after footprint review
- Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_BORN-SI2302_C344009.pdf
- Part Type: Transistor
- Role: Heater MOSFET
- Manufacturer Part Number: SI2302
- Role Details: Overspecified low-side N-MOSFET for 5V/200mA heater PWM channel 2
- Manufacturer Name: BORN
**Pins:**
- D
- G
- S
### Q3 — [SI2302](https://www.flux.ai/jecstronic/si2302~47t.md)
- Manufacturer Name: BORN
- Role: Heater MOSFET
- Role Details: Overspecified low-side N-MOSFET for 5V/200mA heater PWM channel 3
- Allow Substitutes: Yes - logic-level N-MOSFET with low RDS(on) at 3.3V gate after footprint review
- Manufacturer Part Number: SI2302
- Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_BORN-SI2302_C344009.pdf
- Part Type: Transistor
**Pins:**
- D
- G
- S
### Q4 — [SI2302](https://www.flux.ai/jecstronic/si2302~47t.md)
- Datasheet URL: https://datasheet.lcsc.com/lcsc/1912111437_BORN-SI2302_C344009.pdf
- Allow Substitutes: Yes - logic-level N-MOSFET with low RDS(on) at 3.3V gate after footprint review
- Part Type: Transistor
- Manufacturer Part Number: SI2302
- Manufacturer Name: BORN
- Role Details: Overspecified low-side N-MOSFET for 5V/200mA heater PWM channel 4
- Role: Heater MOSFET
**Pins:**
- D
- G
- S
### RT1 — [NCU18XH103F6SRB](https://www.flux.ai/cherepanyadima/ncu18xh103f6srb~53.md)
- Resistance: 10kΩ
- Manufacturer Part Number: ABNTC-0603-103J-3950F-T
- Allow Substitutes: Yes - compatible 10k 0603 NTC with validated beta/tolerance may be substituted
- Part Type: Resistors
- Package or Case Code: R0603
- Datasheet URL: https://abracon.com/Magnetics/inductors/ABNTC-0603.pdf
- Manufacturer Name: Abracon LLC
- Role: Temperature Sensor
- Role Details: 10k NTC thermistor for PCB-mounted heater safety sensing channel 1
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### RT2 — [NCU18XH103F6SRB](https://www.flux.ai/cherepanyadima/ncu18xh103f6srb~53.md)
- Allow Substitutes: Yes - compatible 10k 0603 NTC with validated beta/tolerance may be substituted
- Manufacturer Name: Abracon LLC
- Role: Temperature Sensor
- Package or Case Code: R0603
- Datasheet URL: https://abracon.com/Magnetics/inductors/ABNTC-0603.pdf
- Role Details: 10k NTC thermistor for PCB-mounted heater safety sensing channel 2
- Part Type: Resistors
- Resistance: 10kΩ
- Manufacturer Part Number: ABNTC-0603-103J-3950F-T
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### RT3 — [NCU18XH103F6SRB](https://www.flux.ai/cherepanyadima/ncu18xh103f6srb~53.md)
- Manufacturer Name: Abracon LLC
- Datasheet URL: https://abracon.com/Magnetics/inductors/ABNTC-0603.pdf
- Package or Case Code: R0603
- Part Type: Resistors
- Resistance: 10kΩ
- Manufacturer Part Number: ABNTC-0603-103J-3950F-T
- Allow Substitutes: Yes - compatible 10k 0603 NTC with validated beta/tolerance may be substituted
- Role Details: 10k NTC thermistor for PCB-mounted heater safety sensing channel 3
- Role: Temperature Sensor
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### RT4 — [NCU18XH103F6SRB](https://www.flux.ai/cherepanyadima/ncu18xh103f6srb~53.md)
- Part Type: Resistors
- Manufacturer Part Number: ABNTC-0603-103J-3950F-T
- Resistance: 10kΩ
- Manufacturer Name: Abracon LLC
- Role: Temperature Sensor
- Allow Substitutes: Yes - compatible 10k 0603 NTC with validated beta/tolerance may be substituted
- Datasheet URL: https://abracon.com/Magnetics/inductors/ABNTC-0603.pdf
- Role Details: 10k NTC thermistor for PCB-mounted heater safety sensing channel 4
- Package or Case Code: R0603
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### RT5 — [NCU18XH103F6SRB](https://www.flux.ai/cherepanyadima/ncu18xh103f6srb~53.md)
- Resistance: 10kΩ
- Manufacturer Part Number: ABNTC-0603-103J-3950F-T
- Part Type: Resistors
- Datasheet URL: https://abracon.com/Magnetics/inductors/ABNTC-0603.pdf
- Package or Case Code: R0603
- Allow Substitutes: Yes - compatible 10k 0603 NTC with validated beta/tolerance may be substituted
- Role: Temperature Sensor
- Role Details: 10k NTC thermistor for caddy-corner ambient room sensing A
- Manufacturer Name: Abracon LLC
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### RT6 — [NCU18XH103F6SRB](https://www.flux.ai/cherepanyadima/ncu18xh103f6srb~53.md)
- Allow Substitutes: Yes - compatible 10k 0603 NTC with validated beta/tolerance may be substituted
- Part Type: Resistors
- Role Details: 10k NTC thermistor for caddy-corner ambient room sensing B
- Resistance: 10kΩ
- Manufacturer Part Number: ABNTC-0603-103J-3950F-T
- Manufacturer Name: Abracon LLC
- Package or Case Code: R0603
- Role: Temperature Sensor
- Datasheet URL: https://abracon.com/Magnetics/inductors/ABNTC-0603.pdf
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### SW1 — [PEC11R-4220F-S0024](https://www.flux.ai/jecstronic/pec11r-4220f-s0024~5rr.md)
- Part Type: Sensor
- Manufacturer Part Number: PEC11R-4220F-S0024
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Name: Bourns Inc.
- Datasheet URL: https://www.bourns.com/docs/Product-Datasheets/PEC11R.pdf
- Allow Substitutes: Yes - EC11/PEC11R-compatible encoder variants after mechanical review
- Role: Rotary Encoder
- Role Details: Detented incremental encoder with integrated pushbutton
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
- A [pin A1]
- B [pin B1]
- C [pin C1]
- MH1 [pin MH1]
- MH2 [pin MH2]
### U1 — [ESP32-S3-WROOM-1-N4R2](https://www.flux.ai/jecstronic/esp32-s3-wroom-1-n4r2~32q.md)
- Allow Substitutes: Yes - Espressif ESP32-S3 module variants with same footprint/pinout and antenna requirements may be evaluated
- Role: Controller
- Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-s3-wroom-1_wroom-1u_datasheet_en.pdf
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Name: Espressif Systems
- Manufacturer Part Number: ESP32-S3-WROOM-1-N4R2
- Role Details: ESP32-S3 module with native USB, WiFi, Bluetooth, PCB antenna
- Part Type: Module
**Pins:**
- 3V3 [pin 2]
- EN [pin 3]
- GND_1 [pin 1]
- GND_10 [pin 48]
- GND_11 [pin 49]
- GND_2 [pin 40]
- GND_3 [pin 41]
- GND_4 [pin 42]
- GND_5 [pin 43]
- GND_6 [pin 44]
- GND_7 [pin 45]
- GND_8 [pin 46]
- GND_9 [pin 47]
- IO0 [pin 27]
- IO1 [pin 39]
- IO10 [pin 18]
- IO11 [pin 19]
- IO12 [pin 20]
- IO13 [pin 21]
- IO14 [pin 22]
- IO15 [pin 8]
- IO16 [pin 9]
- IO17 [pin 10]
- IO18 [pin 11]
- IO19 [pin 13]
- IO2 [pin 38]
- IO20 [pin 14]
- IO21 [pin 23]
- IO3 [pin 15]
- IO35 [pin 28]
- IO36 [pin 29]
- IO37 [pin 30]
- IO38 [pin 31]
- IO39 [pin 32]
- IO4 [pin 4]
- IO40 [pin 33]
- IO41 [pin 34]
- IO42 [pin 35]
- IO45 [pin 26]
- IO46 [pin 16]
- IO47 [pin 24]
- IO48 [pin 25]
- IO5 [pin 5]
- IO6 [pin 6]
- IO7 [pin 7]
- IO8 [pin 12]
- IO9 [pin 17]
- RXD0 [pin 36]
- TXD0 [pin 37]
### U2 — [STUSB4500QTR](https://www.flux.ai/lcsc/stusb4500qtr~85y0.md)
- JLCPCB Part Class: Extended Part
- License: https://creativecommons.org/licenses/by/4.0/
- Role: USB-C PD Sink Controller
- Manufacturer Name: ST(意法半导体)
- Part Type: Interface - Controllers
- Allow Substitutes: Yes - alternate Type-C/PD sink controllers may be evaluated if firmware and footprint change are acceptable
- Datasheet URL: https://www.lcsc.com/datasheet/C2678061.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNeR1VbU1BeQ1FYXzsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D
- Role Details: PD sink controller; target 5V rail behavior and source capability detection/management
- Manufacturer Part Number: STUSB4500QTR
- Symbol Style: parametric-v1
- Package or Case Code: QFN-24_L4.0-W4.0-P0.50-BL-EP2.8
- LCSC Part Number: C2678061
**Pins:**
- A_B_SIDE [pin 17]
- ADDR0 [pin 12]
- ADDR1 [pin 13]
- ALERT [pin 19]
- ATTACH [pin 11]
- CC1 [pin 2]
- CC1DB [pin 1]
- CC2 [pin 4]
- CC2DB [pin 5]
- DISCH [pin 9]
- EP [pin 25]
- GND [pin 10]
- GPIO [pin 15]
- NC [pin 3]
- POWER_OK2 [pin 20]
- POWER_OK3 [pin 14]
- RESET [pin 6]
- SCL [pin 7]
- SDA [pin 8]
- VBUS_EN_SNK [pin 16]
- VBUS_VS_DISCH [pin 18]
- VDD [pin 24]
- VREG_1V2 [pin 21]
- VREG_2V7 [pin 23]
- VSYS [pin 22]
### U3 — [AP63203WU-7](https://www.flux.ai/adrian95/ap63203wu-7~o8a.md)
- Manufacturer Name: Diodes Incorporated
- License: https://creativecommons.org/licenses/by/4.0/
- Part Type: Integrated Circuit
- Role Details: Fixed 3.3V 2A buck for ESP32, UI, sensors, and logic; chosen over LDO for no-heatsink thermal margin
- Datasheet URL: https://www.diodes.com/assets/Datasheets/AP63200-AP63201-AP63203-AP63205.pdf
- Manufacturer Part Number: AP63203WU-7
- Role: 3.3V Buck Regulator
- Symbol Style: parametric-v1
- Allow Substitutes: Yes - 3.3V buck regulators with similar pinout/support after validation
**Pins:**
- BST [pin 6]
- EN [pin 2]
- FB [pin 1]
- GND [pin 4]
- SW [pin 5]
- VIN [pin 3]
### U4 — [MP5036AGJ-Z](https://www.flux.ai/monolithicpower/mp5036agj-z~3r.md)
- Allow Substitutes: Yes - equivalent 5V USB eFuse/current-limit switch after current-limit and thermal review
- Manufacturer Name: Monolithic Power Systems
- Manufacturer Part Number: MP5036AGJ-Z
- Role Details: Adjustable input eFuse/current limiter sized around 1.5A-2A after final power budget
- Role: Protection
- Datasheet URL: https://www.monolithicpower.com/en/documentview/productdocument/index/version/2/document_type/Datasheet/lang/en/sku/MP5036A
- Product Info Url: https://www.monolithicpower.com/en/catalog/product/view/id/3436?utm_source=ultralibrarian&utm_medium=component_search&utm_campaign=listing
- Product Image Url: https://www.monolithicpower.com/pub/media/catalog/product/t/a/tac_3.jpg
- Package or Case Code: TSOT23-6_MP5036_MNP
**Pins:**
- DV/DT [pin 6]
- EN [pin 1]
- GND [pin 3]
- ILIMIT [pin 4]
- SOURCE [pin 2]
- VIN [pin 5]
### U5 — [USBLC6-2SC6](https://www.flux.ai/lcsc/usblc6-2sc6~2e9x.md)
- Manufacturer Name: UMW(友台半导体)
- Manufacturer Part Number: USBLC6-2SC6
- LCSC Part Number: C2687116
- JLCPCB Part Class: Extended Part
- Allow Substitutes: Yes - equivalent low-capacitance USB2 ESD arrays may be substituted
- Operating Temperature: -55°C ~ 125°C (TJ)
- Role Details: USB2 D+/D- ESD protection located near USB-C connector
- Maximum Clamping Voltage: 17V
- Breakdown Voltage: 6V
- Datasheet URL: https://www.lcsc.com/datasheet/C2687116.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=FlkNBAIDRQULVABfFAVZBgZVFVZYBgZSQ1NeBVIFQlExVlNRTlhdUVdURFlXXzsOAxUeFF5JWBYZEEoKFBINSQcJGk4dAgUUFAk%3D
- Package or Case Code: SOT-23-6_L2.9-W1.6-P0.95-LS2.8-BL
- Role: ESD Protection
- Power: 150W
- Part Type: ESD Protection Devices
- Peak Pulse Current: 5A
- Symbol Style: parametric-v1
**Pins:**
- GND [pin 2]
- I/O1 [pin 1]
- I/O1 [pin 6]
- I/O2 [pin 3]
- I/O2 [pin 4]
- VBUS [pin 5]
*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/roboticsnerd/esp32-heater-controller~xa](https://www.flux.ai/roboticsnerd/esp32-heater-controller~xa).*
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*Generated from [https://www.flux.ai/roboticsnerd/esp32-heater-controller~xa](https://www.flux.ai/roboticsnerd/esp32-heater-controller~xa)*