# FJ Cruiser Solar Compass
## Description
Dashboard-mounted automotive compass with STM32 control, LIS3MDL heading sensor, three orange 7-segment digits, solar-assisted battery charging, protected vehicle power input, and dimmer/off control for Toyota FJ Cruiser integration.
## Project Details
- **Owner:** brooks
- **Created:** 4/21/2026
- **Last Updated:** 4/21/2026
- **Visibility:** Public
## Key Components
### D1 — [0.3" CC Orange 7 Segment Display](https://www.flux.ai/corynrobinson/0p3-cc-orange-7-segment-display~t8.md)
- Role Details: One of three common-cathode orange 7-segment heading digits
- Part Type: LED
- Forward Voltage: 2V
- Purchase Url: https://www.digikey.com/en/products/detail/kingbright/ACSC03-41SEKWA-F01/3084745
- Datasheet URL: https://www.kingbrightusa.com/images/catalog/SPEC/ACSC03-41SEKWA-F01.pdf
- Current: 10mA
- Package: Through Hole
- Role: Display Digit
- Manufacturer Name: Kingbright
- Manufacturer Part Number: ACSC03-41SEKWA-F01
**Pins:**
- a [pin 7]
- b [pin 6]
- c [pin 4]
- Cathode1 [pin 3]
- Cathode2 [pin 8]
- d [pin 2]
- dp [pin 5]
- e [pin 1]
- f [pin 9]
- g [pin 10]
### D2 — [0.3" CC Orange 7 Segment Display](https://www.flux.ai/corynrobinson/0p3-cc-orange-7-segment-display~t8.md)
- Package: Through Hole
- Purchase Url: https://www.digikey.com/en/products/detail/kingbright/ACSC03-41SEKWA-F01/3084745
- Role Details: One of three common-cathode orange 7-segment heading digits
- Role: Display Digit
- Forward Voltage: 2V
- Part Type: LED
- Manufacturer Part Number: ACSC03-41SEKWA-F01
- Manufacturer Name: Kingbright
- Current: 10mA
- Datasheet URL: https://www.kingbrightusa.com/images/catalog/SPEC/ACSC03-41SEKWA-F01.pdf
**Pins:**
- a [pin 7]
- b [pin 6]
- c [pin 4]
- Cathode1 [pin 3]
- Cathode2 [pin 8]
- d [pin 2]
- dp [pin 5]
- e [pin 1]
- f [pin 9]
- g [pin 10]
### D3 — [0.3" CC Orange 7 Segment Display](https://www.flux.ai/corynrobinson/0p3-cc-orange-7-segment-display~t8.md)
- Role Details: One of three common-cathode orange 7-segment heading digits
- Purchase Url: https://www.digikey.com/en/products/detail/kingbright/ACSC03-41SEKWA-F01/3084745
- Role: Display Digit
- Part Type: LED
- Forward Voltage: 2V
- Datasheet URL: https://www.kingbrightusa.com/images/catalog/SPEC/ACSC03-41SEKWA-F01.pdf
- Package: Through Hole
- Current: 10mA
- Manufacturer Name: Kingbright
- Manufacturer Part Number: ACSC03-41SEKWA-F01
**Pins:**
- a [pin 7]
- b [pin 6]
- c [pin 4]
- Cathode1 [pin 3]
- Cathode2 [pin 8]
- d [pin 2]
- dp [pin 5]
- e [pin 1]
- f [pin 9]
- g [pin 10]
### D4 — [SMBJ24A](https://www.flux.ai/cherepanyadima/smbj24a~2b.md)
- Role Details: Automotive input TVS clamp on the vehicle supply rail
- Part Type: TVS
- Role: TVS Protection
- Manufacturer Name: Taiwan Semiconductor Corporation
- Package: SMB
- Manufacturer Part Number: SMBJ24A-TR
- Datasheet URL: https://services.taiwansemi.com/storage/resources/datasheet/SMBJ%20SERIES_R2104.pdf
**Pins:**
- A [pin 2]
- K [pin 1]
### D5 — [SS14-E3/5AT](https://www.flux.ai/adrian95/ss14-e35at~pyx.md)
- Manufacturer Name: Vishay General Semiconductor - Diodes Division
- Part Type: Diode
- Role Details: Power-path isolation diode for low-loss input steering
- Datasheet URL: https://www.vishay.com/docs/88746/ss12.pdf
- Manufacturer Part Number: SS14-E3/5AT
- Role: Schottky Diode
- License: https://creativecommons.org/licenses/by/4.0/
- Package: SMA
**Pins:**
- A [pin 2]
- K [pin 1]
### F1 — [MF-PSML075/12-2](https://www.flux.ai/adrian95/mf-psml07512-2~j0j.md)
- Manufacturer Part Number: MF-PSML075/12-2
- Part Type: Fuse
- Role: Input Fuse
- License: https://creativecommons.org/licenses/by/4.0/
- Datasheet URL: https://www.bourns.com/docs/Product-Datasheets/MF-PSML-X.pdf
- Role Details: Resettable PTC fuse for vehicle input fault protection
- Manufacturer Name: Bourns Inc.
- Package: 0805
**Pins:**
- P1 [pin 1]
- P2 [pin 2]
### IC1 — [SPV1040TTR](https://www.flux.ai/jecstronic/spv1040ttr~36h.md)
- Manufacturer Part Number: SPV1040TTR
- Part Type: Integrated Circuit
- License: https://creativecommons.org/licenses/by/4.0/
- Package: TSSOP-8
- Role Details: Single-cell solar charger with MPPT to charge the storage cell from the dashboard solar panel
- Role: Solar Charger
- Manufacturer Name: STMicroelectronics
- Datasheet URL: https://www.st.com/content/ccc/resource/technical/document/datasheet/0d/30/c2/1a/92/03/48/cb/CD00287506.pdf/files/CD00287506.pdf/jcr:content/translations/en.CD00287506.pdf
**Pins:**
- GND [pin 2]
- ICTRL_MINUS [pin 6]
- ICTRL_PLUS [pin 7]
- LX [pin 3]
- MPP-SET [pin 1]
- VCTRL [pin 5]
- VOUT [pin 4]
- XSHUT [pin 8]
### J1 — [Type-C-2.0-6Pin](https://www.flux.ai/jharwinbarrozo/type-c-2p0-6pin~wh.md)
- Manufacturer Name: CIKI
- Role: USB-C Power Input
- Package: SMT
- Role Details: Optional 5V input for service power and charging path
- Datasheet URL: https://datasheet.lcsc.com/lcsc/2204071830_CIKI-Type-C-2-0-6Pin_C2987385.pdf
- Manufacturer Part Number: Type-C-2.0-6Pin
- Part Type: Connector
**Pins:**
- CC1
- CC2
- GND
- GND__1
- SHIELD
- SHIELD__1
- SHIELD__2
- SHIELD__3
- V-BUS
- V-BUS__1
### J2 — [B2B-PH-K-S](https://www.flux.ai/adrian95/b2b-ph-k-s~fx.md)
- Manufacturer Part Number: B2B-PH-K-S
- Part Type: Connector
- License: https://creativecommons.org/licenses/by/4.0/
- Package or Case Code: JST_B2B-PH-K-S
- Package: Through Hole
- Role: Battery Connector
- Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf
- Manufacturer Name: JST
- Role Details: 2-pin JST-PH connector for the single-cell battery
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
### J3 — [B2P-VH(LF)(SN)](https://www.flux.ai/adrian95/b2p-vhlfsn~cao.md)
- Manufacturer Name: JST Sales America Inc.
- Manufacturer Part Number: B2P-VH(LF)(SN)
- Role: Vehicle Power Input
- Part Type: Connector
- License: https://creativecommons.org/licenses/by/4.0/
- Role Details: 2-pin locking connector for protected automotive 12V input from dashboard harness
- Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/eVH.pdf
- Package: Through Hole
**Pins:**
- P1 [pin 1]
- P2 [pin 2]
### J4 — [ARM JTAG SWD 10Pin 0.05" Connector](https://www.flux.ai/vasy_skral/arm-jtag-swd-10pin-005-connector~y0b.md)
- Role Details: ARM Cortex standard 2x5 1.27mm SWD connector for programming and debug
- Manufacturer Name: Analog Devices
- Package: SMD
- Datasheet URL: https://suddendocs.samtec.com/catalog_english/ftsh_smt.pdf
- Manufacturer Part Number: FTSH-105-01-L-DV-007-K
- Part Type: Connector
- Symbol Style: parametric-v1
- Role: SWD Debug Header
**Pins:**
- ~RESET~ [pin 10]
- GND [pin 5]
- GND [pin 3]
- GNDDetect [pin 9]
- NC/TDI [pin 8]
- SWDCLK/TCK [pin 4]
- SWDIO/TMS [pin 2]
- SWO/TDO [pin 6]
- VTref [pin 1]
### RV1 — [PTV09A-4020F-B103](https://www.flux.ai/jecstronic/ptv09a-4020f-b103~9bb.md)
- Datasheet URL: https://www.bourns.com/docs/Product-Datasheets/PTV09.pdf
- Part Type: Potentiometer
- Manufacturer Part Number: PTV09A-4020F-B103
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Dimmer Potentiometer
- Role Details: 10k linear user brightness control input for MCU ADC
- Package: Through Hole
- Manufacturer Name: Bourns Inc.
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
- 3 [pin 3]
- MH1 [pin 4]
- MH2 [pin 5]
### SW1 — [PTR902-2015K-A104](https://www.flux.ai/jecstronic/ptr902-2015k-a104~709.md)
- Manufacturer Name: Texas Instruments Inc.
- Role Details: Rotary dimmer knob with integrated switch for brightness control and system off input
- Role: Dimmer Control
- Package: Through Hole
- Manufacturer Part Number: PTR902-2015K-A104
- License: https://creativecommons.org/licenses/by/4.0/
- Part Type: Potentiometer
- Datasheet URL: https://www.bourns.com/docs/Product-Datasheets/PTR90.pdf
**Pins:**
- R1_1 [pin 1]
- R1_2 [pin 2]
- R1_3 [pin 3]
- R2_1 [pin 4]
- R2_2 [pin 5]
- R2_3 [pin 6]
- SW_1 [pin 7]
- SW_2 [pin 8]
### U1 — [STM32L031G6U6S](https://www.flux.ai/vasyl/stm32l031g6u6s~zrh.md)
- Manufacturer Part Number: STM32L031G6U6S
- Role: Microcontroller
- Datasheet URL: https://www.st.com/resource/en/datasheet/stm32l031c6.pdf
- Manufacturer Name: STMicroelectronics
- Package: UFQFPN-28
- Part Type: Microcontroller
- Role Details: Main controller for compass heading calculation, display update, dimmer ADC input, and power-state control
**Pins:**
- BOOT0 [pin 1]
- NRST [pin 4]
- P14 [pin 22]
- PA0 [pin 6]
- PA1 [pin 7]
- PA10 [pin 20]
- PA13 [pin 21]
- PA14 [pin 23]
- PA2 [pin 8]
- PA3 [pin 9]
- PA4 [pin 10]
- PA5 [pin 11]
- PA6 [pin 12]
- PA7 [pin 13]
- PA8 [pin 18]
- PA9 [pin 19]
- PB0 [pin 14]
- PB1 [pin 15]
- PB3 [pin 24]
- PB4 [pin 25]
- PB5 [pin 26]
- PB6 [pin 27]
- PB7 [pin 28]
- PC14 [pin 2]
- PC15 [pin 3]
- VDD [pin 17]
- VDDA [pin 5]
- VSS [pin 16]
### U2 — [LIS3MDL](https://www.flux.ai/kicad-part-library/lis3mdl~yb6.md)
- Manufacturer Part Number: LIS3MDL
- Role Details: I2C compass sensor used for heading measurement and calibration
- Package: LGA-12
- Package or Case Code: LGA-12_2x2mm_P0.5mm
- Role: Magnetometer
- Datasheet URL: https://www.st.com/resource/en/datasheet/lis3mdl.pdf
**Pins:**
- ~{CS} [pin 10]
- C1 [pin 4]
- DRDY [pin 8]
- GND [pin 12]
- GND [pin 3]
- GND [pin 2]
- INT [pin 7]
- SCL/SPC [pin 1]
- SDA/SDI/SDO [pin 11]
- SDO/SA1 [pin 9]
- Vdd [pin 5]
- Vdd_IO [pin 6]
### U3 — [MAX7219EWG+](https://www.flux.ai/jharwinbarrozo/max7219ewgplus~kjc.md)
- Role Details: SPI-controlled 7-segment LED driver for three orange digits with programmable brightness
- Part Type: Integrated Circuit
- Manufacturer Name: Maxim Integrated
- Package: SOIC-24
- Manufacturer Part Number: MAX7219EWG+
- Role: Display Driver
- Datasheet URL: https://datasheets.maximintegrated.com/en/ds/MAX7219-MAX7221.pdf
**Pins:**
- 1 / DIN
- 10 / DIG_5
- 11 / DIG_1
- 12 / LOAD
- 13 / CLK
- 14 / SEG_A
- 15 / SEG_F
- 16 / SEG_B
- 17 / SEG_G
- 18 / ISET
- 19 / V+
- 2 / DIG_0
- 20 / SEG_C
- 21 / SEG_E
- 22 / SEG_DP
- 23 / SEG_D
- 24 / DOUT
- 3 / DIG_4
- 4 / GND
- 5 / DIG_6
- 6 / DIG_2
- 7 / DIG_3
- 8 / DIG_7
- 9 / GND__1
### U4 — [MPQ4433GLE-AEC1-Z](https://www.flux.ai/monolithicpower/mpq4433gle-aec1-z~t91.md)
- Manufacturer Part Number: MPQ4433GLE-AEC1-Z
- Package: QFN-3x4
- Datasheet URL: https://www.monolithicpower.com/en/documentview/productdocument/index/version/2/document_type/Datasheet/lang/en/sku/MPQ4433-AEC1
- Manufacturer Name: Monolithic Power Systems
- Role: Buck Regulator
- Role Details: AEC-qualified automotive step-down regulator generating the protected 5V rail from vehicle input
- Package or Case Code: QFN-3x4_MPQ4433_MNP
- Product Info Url: https://www.monolithicpower.com/en/catalog/product/view/id/530?utm_source=ultralibrarian&utm_medium=component_search&utm_campaign=listing
- Product Image Url: https://www.monolithicpower.com/pub/media/catalog/product/M/P/MPQ4433-AEC1_530_1.jpg
**Pins:**
- AGND [pin 13]
- BIAS [pin 8]
- BST [pin 11]
- EN [pin 5]
- FB [pin 15]
- FREQ [pin 16]
- PG [pin 7]
- PGND [pin 4]
- PGND [pin 9]
- PHASE [pin 1]
- SS [pin 14]
- SW [pin 10]
- SW [pin 3]
- SYNC [pin 6]
- VCC [pin 12]
- VIN [pin 2]
### U5 — [MCP1700T-3302E-TT](https://www.flux.ai/adrian95/mcp1700t-3302e-tt~h60.md)
- Role Details: 3.3V post-regulator for low-noise logic and sensor power
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Part Number: MCP1700T-3302E/TT
- Datasheet URL: https://datasheet.octopart.com/MCP1700T-3302E/TT-Microchip-datasheet-532260.pdf
- Part Type: Integrated Circuit
- Package: SOT-23-3
- Manufacturer Name: Microchip Technology
- Role: LDO
**Pins:**
- GND [pin 1]
- VI [pin 3]
- VO [pin 2]
### U6 — [LM5050-2](https://www.flux.ai/kicad-part-library/lm5050-2~os.md)
- Datasheet URL: http://www.ti.com/lit/ds/symlink/lm5050-2.pdf
- Role: Reverse Polarity Protection
- Package or Case Code: TSOT-23-6
- Manufacturer Name: Texas Instruments Inc.
- Package: TSOT-23-6
- Manufacturer Part Number: LM5050-2
- Role Details: Automotive input ideal-diode controller ahead of VIN_PROTECTED rail
**Pins:**
- ~{FGD} [pin 1]
- GATE [pin 5]
- GND [pin 2]
- IN [pin 4]
- OFF [pin 3]
- OUT [pin 6]
*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/brooks/fj-cruiser-solar-compass~cd](https://www.flux.ai/brooks/fj-cruiser-solar-compass~cd).*
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*Generated from [https://www.flux.ai/brooks/fj-cruiser-solar-compass~cd](https://www.flux.ai/brooks/fj-cruiser-solar-compass~cd)*