(kicad_pcb
  (version 20211014)
  (generator "jayis1 AlloyScan PCB Layout")
  (general (thickness 1.6) (legacy_teardrops no))
  (paper "A4")
  (title_block
    (title "AlloyScan — Multi-Frequency Eddy Current Alloy Identifier")
    (date "2026-07-24")
    (rev "1.0")
    (company "jayis1")
    (comment 1 "Open-source handheld metal alloy scanner")
    (comment 2 "4-layer FR-4, 34x28mm")
    (comment 3 "CERN-OHL-S v2")
  )
  (layers
    (0 "F.Cu" signal)
    (1 "In1.Cu" signal "GND")
    (2 "In2.Cu" signal "PWR")
    (31 "B.Cu" signal)
    (32 "B.Adhes" user "B.Adhesive")
    (33 "F.Adhes" user "F.Adhesive")
    (34 "B.Paste" user)
    (35 "F.Paste" user)
    (36 "B.SilkS" user "B.Silkscreen")
    (37 "F.SilkS" user "F.Silkscreen")
    (38 "B.Mask" user)
    (39 "F.Mask" user)
    (40 "Dwgs.User" user "User.Drawings")
    (41 "Cmts.User" user "User.Comments")
    (42 "Eco1.User" user "User.Eco1")
    (43 "Eco2.User" user "User.Eco2")
    (44 "Edge.Cuts" user)
    (45 "Margin" user)
    (46 "B.CrtYd" user "B.Courtyard")
    (47 "F.CrtYd" user "F.Courtyard")
    (48 "B.Fab" user)
    (49 "F.Fab" user)
  )
  (setup
    (stackup
      (layer "F.Cu" (type "copper") (thickness 0.035))
      (layer "dielectric 1" (type "core") (thickness 0.2) (material "FR4"))
      (layer "In1.Cu" (type "copper") (thickness 0.035))
      (layer "dielectric 2" (type "core") (thickness 1.0) (material "FR4"))
      (layer "In2.Cu" (type "copper") (thickness 0.035))
      (layer "dielectric 3" (type "core") (thickness 0.2) (material "FR4"))
      (layer "B.Cu" (type "copper") (thickness 0.035))
    )
    (pad_to_mask_clearance 0.05)
    (pcbplotparams (layerselection 0x00010fc_ffffffff) (usegerberextensions false)
      (usegerberattributes true) (usegerberadvancedattributes true)
      (creategerberjobfile true) (svgprecision 6) (excludeedgelayer true)
      (plotframeref false) (viasonmask false) (mode 1) (useauxorigin false)
      (hpglpennumber 1) (hpglpenspeed 10) (hpglpendepth 0.02) (hpglpenoverlay 0)
      (psnegative false) (psa4output false) (plotreference true) (plotvalue true)
      (plotinvisibletext false) (sketchpadsonfab false) (subtractmaskfromsilk true)
      (outputformat 1) (mirror false) (drillshape 0) (scaleselection 1)
      (outputdirectory "gerbers/"))
  )

  (net 0 "")
  (net 1 "GND")
  (net 2 "+3V3")
  (net 3 "+5V")
  (net 4 "-5V")
  (net 5 "VBAT")
  (net 6 "VDD")
  (net 7 "/DAC_OUT")
  (net 8 "/ADC_IN")
  (net 9 "/SPI1_SCK")
  (net 10 "/SPI1_MISO")
  (net 11 "/SPI1_CS")
  (net 12 "/SPI2_SCK")
  (net 13 "/SPI2_MOSI")
  (net 14 "/SPI2_CS")
  (net 15 "/OLED_DC")
  (net 16 "/OLED_RST")
  (net 17 "/SPI3_SCK")
  (net 18 "/SPI3_MISO")
  (net 19 "/SPI3_MOSI")
  (net 20 "/SPI3_CS")
  (net 21 "/USART2_TX")
  (net 22 "/USART2_RX")
  (net 23 "/I2C3_SCL")
  (net 24 "/I2C3_SDA")
  (net 25 "/TRIGGER")
  (net 26 "/BTN_UP")
  (net 27 "/BTN_DOWN")
  (net 28 "/BTN_OK")
  (net 29 "/LED_GREEN")
  (net 30 "/LED_YELLOW")
  (net 31 "/LED_RED")
  (net 32 "/BUZZER")
  (net 33 "/AMP_EN")
  (net 34 "/COIL_EXC")
  (net 35 "/COIL_SENSE")
  (net 36 "/BAT_MON")
  (net 37 "/CHARGE_STAT")
  (net 38 "N-0001")
  (net 39 "N-0002")

  ; ---- Footprints ----

  (footprint "Package_DFN_QFN:QFN-68-1EP_7x7mm_P0.35mm"
    (layer "F.Cu")
    (tedit 0)
    (attr smd)
    (at 12 10)
    (property "Reference" "U1")
    (property "Value" "STM32G474CEU6")
    (property "Footprint" "Package_DFN_QFN:QFN-68-1EP_7x7mm_P0.35mm")
    (property "Datasheet" "https://www.st.com/resource/en/datasheet/stm32g474ce.pdf")
    (property "Description" "MCU: STM32G474 Cortex-M4 @ 170MHz")
    (property "Manufacturer" "STMicroelectronics")
    (property "MPN" "STM32G474CEU6")
    (property "Author" "jayis1")
  )

  (footprint "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm"
    (layer "F.Cu")
    (at 22 6)
    (property "Reference" "U2")
    (property "Value" "THS3091D")
    (property "Footprint" "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm")
    (property "MPN" "THS3091D")
    (property "Description" "High-speed current-feedback op-amp for coil excitation")
    (property "Author" "jayis1")
  )

  (footprint "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm"
    (layer "F.Cu")
    (at 22 12)
    (property "Reference" "U3")
    (property "Value" "AD8429ARZ")
    (property "Footprint" "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm")
    (property "MPN" "AD8429ARZ")
    (property "Description" "Low-noise instrumentation amplifier G=100")
    (property "Author" "jayis1")
  )

  (footprint "Package_DFN_QFN:DFN-8-1EP_3x3mm_P0.5mm_EP1.7x2.4mm"
    (layer "F.Cu")
    (at 22 18)
    (property "Reference" "U4")
    (property "Value" "ADS8866IDRCR")
    (property "Footprint" "Package_DFN_QFN:DFN-8-1EP_3x3mm_P0.5mm")
    (property "MPN" "ADS8866IDRCR")
    (property "Description" "16-bit 1MSPS SAR ADC (SPI)")
    (property "Author" "jayis1")
  )

  (footprint "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm"
    (layer "F.Cu")
    (at 6 6)
    (property "Reference" "U5")
    (property "Value" "MAX7403CPA")
    (property "Footprint" "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm")
    (property "MPN" "MAX7403CPA+")
    (property "Description" "Switched-cap 700kHz Bessel LPF")
    (property "Author" "jayis1")
  )

  (footprint "RF_Module:BMD-300"
    (layer "F.Cu")
    (at 6 18)
    (property "Reference" "U6")
    (property "Value" "BMD-300")
    (property "Footprint" "RF_Module:BMD-300")
    (property "MPN" "BMD-300")
    (property "Description" "BLE 5.0 module (Nordic nRF52832)")
    (property "Author" "jayis1")
  )

  (footprint "Display:OLED_128x64_1.3in_SH1106"
    (layer "F.Cu")
    (at 15 3)
    (property "Reference" "DISP1")
    (property "Value" "SH1106_1.3_OLED")
    (property "Footprint" "Display:OLED_128x64_1.3in")
    (property "MPN" "SH1106 OLED 1.3in")
    (property "Description" "1.3 inch OLED 128x64 monochrome display")
    (property "Author" "jayis1")
  )

  (footprint "Package_SO:SOIC-16_3.9x9.9mm_P1.27mm"
    (layer "F.Cu")
    (at 6 24)
    (property "Reference" "U7")
    (property "Value" "W25Q128JVSIQ")
    (property "Footprint" "Package_SO:SOIC-16_3.9x9.9mm_P1.27mm")
    (property "MPN" "W25Q128JVSIQ")
    (property "Description" "16 MB SPI flash")
    (property "Author" "jayis1")
  )

  (footprint "Sensor_VL53L0X:VL53L0X"
    (layer "F.Cu")
    (at 28 24)
    (property "Reference" "U8")
    (property "Value" "VL53L0X")
    (property "Footprint" "Sensor:VL53L0X")
    (property "MPN" "VL53L0X")
    (property "Description" "Time-of-flight laser distance sensor")
    (property "Author" "jayis1")
  )

  (footprint "Package_TO_SOT_SMD:SOT-23-6"
    (layer "F.Cu")
    (at 28 14)
    (property "Reference" "U9")
    (property "Value" "TPS63020DSJR")
    (property "Footprint" "Package_TO_SOT_SMD:SOT-23-6")
    (property "MPN" "TPS63020DSJR")
    (property "Description" "Buck-boost converter 3.3V output")
    (property "Author" "jayis1")
  )

  (footprint "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm"
    (layer "F.Cu")
    (at 28 8)
    (property "Reference" "U10")
    (property "Value" "LM7660IN")
    (property "Footprint" "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm")
    (property "MPN" "LM7660IN")
    (property "Description" "Voltage inverter for -5V supply")
    (property "Author" "jayis1")
  )

  (footprint "Package_TO_SOT_SMD:SOT-23-3"
    (layer "F.Cu")
    (at 2 22)
    (property "Reference" "U11")
    (property "Value" "AP2112K-3.3")
    (property "Footprint" "Package_TO_SOT_SMD:SOT-23-3")
    (property "MPN" "AP2112K-3.3")
    (property "Description" "3.3V LDO for BLE/display")
    (property "Author" "jayis1")
  )

  (footprint "Package_DFN:TP4056"
    (layer "F.Cu")
    (at 2 14)
    (property "Reference" "U12")
    (property "Value" "TP4056")
    (property "Footprint" "Package_SO:SOIC-8_3.9x4.9mm_P1.27mm")
    (property "MPN" "TP4056")
    (property "Description" "USB-C Li-ion battery charger")
    (property "Author" "jayis1")
  )

  ; ---- Passive components ----

  (footprint "Inductor_SMD:L_0603_1608Metric"
    (layer "F.Cu")
    (at 24 14)
    (property "Reference" "L1")
    (property "Value" "10uH")
    (property "Author" "jayis1")
  )

  (footprint "Inductor_SMD:L_0805_2012Metric"
    (layer "F.Cu")
    (at 26 16)
    (property "Reference" "L2")
    (property "Value" "22uH")
    (property "Author" "jayis1")
  )

  (footprint "Capacitor_SMD:C_0402_1005Metric"
    (layer "F.Cu")
    (at 14 16)
    (property "Reference" "C1")
    (property "Value" "100nF")
    (property "Author" "jayis1")
  )

  (footprint "Capacitor_SMD:C_0402_1005Metric"
    (layer "F.Cu")
    (at 14 18)
    (property "Reference" "C2")
    (property "Value" "100nF")
    (property "Author" "jayis1")
  )

  (footprint "Capacitor_SMD:C_0805_2012Metric"
    (layer "F.Cu")
    (at 14 20)
    (property "Reference" "C3")
    (property "Value" "10uF")
    (property "Author" "jayis1")
  )

  (footprint "Capacitor_SMD:C_0603_1608Metric"
    (layer "F.Cu")
    (at 16 16)
    (property "Reference" "C4")
    (property "Value" "1uF")
    (property "Author" "jayis1")
  )

  (footprint "Resistor_SMD:R_0402_1005Metric"
    (layer "F.Cu")
    (at 18 16)
    (property "Reference" "R1")
    (property "Value" "10k")
    (property "Author" "jayis1")
  )

  (footprint "Resistor_SMD:R_0402_1005Metric"
    (layer "F.Cu")
    (at 18 18)
    (property "Reference" "R2")
    (property "Value" "10k")
    (property "Author" "jayis1")
  )

  (footprint "Resistor_SMD:R_0402_1005Metric"
    (layer "F.Cu")
    (at 18 20)
    (property "Reference" "R3")
    (property "Value" "4k7")
    (property "Author" "jayis1")
  )

  (footprint "Resistor_SMD:R_0402_1005Metric"
    (layer "F.Cu")
    (at 20 20)
    (property "Reference" "R4")
    (property "Value" "4k7")
    (property "Author" "jayis1")
  )

  (footprint "Resistor_SMD:R_0805_2012Metric"
    (layer "F.Cu")
    (at 20 22)
    (property "Reference" "R5")
    (property "Value" "100k")
    (property "Author" "jayis1")
  )

  (footprint "Resistor_SMD:R_0805_2012Metric"
    (layer "F.Cu")
    (at 20 24)
    (property "Reference" "R6")
    (property "Value" "100k")
    (property "Author" "jayis1")
  )

  (footprint "Resistor_SMD:R_0603_1608Metric"
    (layer "F.Cu")
    (at 22 22)
    (property "Reference" "R7")
    (property "Value" "220")
    (property "Description" "Buzzer current limit")
    (property "Author" "jayis1")
  )

  ; ---- Connectors ----

  (footprint "Connector_USB:USB-C_Receptacle_HRO"
    (layer "F.Cu")
    (at 2 28)
    (property "Reference" "J1")
    (property "Value" "USB-C")
    (property "Author" "jayis1")
  )

  (footprint "Connector_PinHeader_2.54mm:PinHeader_1x04"
    (layer "F.Cu")
    (at 30 20)
    (property "Reference" "J2")
    (property "Value" "SWD")
    (property "Description" "SWD debug header")
    (property "Author" "jayis1")
  )

  (footprint "Connector_Coil:Probe_Coil"
    (layer "F.Cu")
    (at 28 2)
    (property "Reference" "L3")
    (property "Value" "Excitation_Coil")
    (property "Description" "Ferrite-cored excitation coil, 80 turns")
    (property "Author" "jayis1")
  )

  (footprint "Connector_Coil:Probe_Coil"
    (layer "F.Cu")
    (at 30 4)
    (property "Reference" "L4")
    (property "Value" "Sense_Coil")
    (property "Description" "Ferrite-cored sense coil, 200 turns")
    (property "Author" "jayis1")
  )

  ; ---- Board outline ----
  (gr_line (start 0 0) (end 34 0) (layer "Edge.Cuts") (width 0.1))
  (gr_line (start 34 0) (end 34 28) (layer "Edge.Cuts") (width 0.1))
  (gr_line (start 34 28) (end 0 28) (layer "Edge.Cuts") (width 0.1))
  (gr_line (start 0 28) (end 0 0) (layer "Edge.Cuts") (width 0.1))

  ; ---- Silkscreen ----
  (gr_text "AlloyScan v1.0" (at 12 2) (layer "F.SilkS") (effects (font (size 0.8 0.8))))
  (gr_text "jayis1 2026" (at 12 26) (layer "F.SilkS") (effects (font (size 0.6 0.6))))

  ; ---- Vias for ground stitching ----
  (via (at 4 4) (size 0.3) (drill 0.15) (layers "F.Cu" "B.Cu") (net 1))
  (via (at 30 4) (size 0.3) (drill 0.15) (layers "F.Cu" "B.Cu") (net 1))
  (via (at 4 24) (size 0.3) (drill 0.15) (layers "F.Cu" "B.Cu") (net 1))
  (via (at 30 24) (size 0.3) (drill 0.15) (layers "F.Cu" "B.Cu") (net 1))
  (via (at 17 14) (size 0.3) (drill 0.15) (layers "F.Cu" "B.Cu") (net 1))
)