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Koyomi LVDS HAT

A Raspberry Pi RGB/DPI-to-LVDS display board for driving the Sony VAIO P's 1600 x 768 panel, with a compact four-layer production candidate and documented fabrication evidence.

KiCadRaspberry PiLVDSVAIO POpen hardware

R2.7 fabrication candidate Drag to rotate · Scroll to zoom

Default branchmain

LicenseCERN-OHL-S-2.0

Current revisionR2.7 fabrication candidate

UpdatedAug 21, 2026

README

Project Koyomi — display testing HAT

A tested Raspberry Pi HAT for driving the Sony VAIO P display through the Pi's DPI interface and a Texas Instruments SN75LVDS83B LVDS transmitter.

The Toshiba LT080EE04100 panel has no backlight driver, so Koyomi breaks out its backlight connections for external driver development.

TensorFleet's copy adds the missing F.Mask apertures to both DLP2ADN121HL4L filters. The change creates exactly 16 solder-mask openings that KiCad DRC did not flag as missing.

The compact R2.7 variant keeps the same electrical interface and 23-part fitted set in a 29.33% smaller four-layer board.

Raspberry Pi display configuration

dtoverlay=vc4-kms-dpi-generic
dtparam=hactive=1600,hfp=32,hsync=65,hbp=97
dtparam=vactive=768,vfp=1,vsync=1,vbp=8
dtparam=clock-frequency=83600000,rgb666
dtoverlay=i2c-gpio,i2c_gpio_sda=23,i2c_gpio_scl=24

Project essentials

What this board does

Understand the board’s purpose and major capabilities at a glance.

SN75LVDS83B RGB/DPI-to-LVDS conversion
1600 x 768 Toshiba LT080EE04100 panel support
58.0 x 22.2 mm compact R2.7 production candidate
Four-layer board with 23 fitted parts, all on the top side
KiCad source, STEP models, renders, BOM/CPL and reproducible audits

Release status

Prototype readiness

See whether the design is electrically and mechanically ready.

✓

Electrical checks passDRC, ERC and interface audit

DRC errors: 0
ERC errors: 0
Unconnected pads: 0
Interface audit: 11 nets pass

Sony VAIO knowledge base

Project documentation

Browse the design history, fabrication notes, verification reports, and mechanical work already documented in the repository.

22 documents

Start here 2

Koyomi LVDS HAT overview Tested Sony VAIO P display hardware, setup notes and project background. README.md GPIO breakout board Companion breakout documentation for Raspberry Pi display bring-up. gpio-breakout/README.md

Fabrication 3

R2.6 production package Production-baseline fabrication package and release guidance. fab/r2.6-compact-rgb-production-jlc-candidate/README.md R2.7 production package Compact fabrication candidate, assembly outputs and sourcing gates. fab/r2.7-compact-rgb-production-jlc-candidate/README.md GPIO breakout A1 fabrication Manufacturing notes for the companion GPIO breakout revision. gpio-breakout/fab/a1-jlc/README.md

Design revisions 8

Compact RGB R2.0 First compact RGB-to-LVDS board revision. variants/koyomi-lvds-hat-rgb-compact-r2.0/README.md Single-side R2.1 Single-side assembly iteration and design rationale. variants/koyomi-lvds-hat-rgb-compact-r2.1-single-side/README.md Backlight FFC R2.2 Backlight FFC interface revision for the VAIO P panel. variants/koyomi-lvds-hat-rgb-compact-r2.2-backlight-ffc/README.md Routed R2.3 Routed compact-board iteration and implementation notes. variants/koyomi-lvds-hat-rgb-compact-r2.3-routed/README.md Sideband bridge R2.4 Sideband bridge changes and electrical design notes. variants/koyomi-lvds-hat-rgb-compact-r2.4-sideband-bridge/README.md Production R2.6 Electrically complete compact production baseline. variants/koyomi-lvds-hat-rgb-compact-r2.6-production/README.md 30% floorplan R2.7 Smaller mechanical floorplan study and its design constraints. variants/koyomi-lvds-hat-rgb-compact-r2.7-30pct-floorplan/README.md R2.7 fabrication status Explicit readiness and do-not-manufacture status for the floorplan study. variants/koyomi-lvds-hat-rgb-compact-r2.7-30pct-floorplan/FABRICATION_STATUS.md

Verification 7

R2.0 verification Electrical and physical checks recorded for revision R2.0. variants/koyomi-lvds-hat-rgb-compact-r2.0/reports/verification.md R2.1 verification Electrical and physical checks recorded for revision R2.1. variants/koyomi-lvds-hat-rgb-compact-r2.1-single-side/reports/verification.md R2.2 verification Electrical and physical checks recorded for revision R2.2. variants/koyomi-lvds-hat-rgb-compact-r2.2-backlight-ffc/reports/verification.md R2.3 verification Routing and validation evidence for revision R2.3. variants/koyomi-lvds-hat-rgb-compact-r2.3-routed/reports/verification.md R2.4 verification Sideband bridge validation evidence for revision R2.4. variants/koyomi-lvds-hat-rgb-compact-r2.4-sideband-bridge/reports/verification.md R2.6 verification Production-baseline electrical, interface and fabrication checks. variants/koyomi-lvds-hat-rgb-compact-r2.6-production/reports/verification.md R2.7 verification Recorded validation state for the reduced floorplan revision. variants/koyomi-lvds-hat-rgb-compact-r2.7-30pct-floorplan/reports/verification.md

Mechanical 2

R2.3 printable models Mechanical print-model notes for enclosure and fit checks. variants/koyomi-lvds-hat-rgb-compact-r2.3-routed/mechanical/print-models/README.md R2.7 printable models Mechanical print-model notes for the reduced floorplan. variants/koyomi-lvds-hat-rgb-compact-r2.7-30pct-floorplan/mechanical/print-models/README.md

Repository map

Important files

Open the primary design sources, project setup, and release evidence.

koyomi-lvds-hat.kicad_sch Canonical electrical design

koyomi-lvds-hat.kicad_pcb Tested upstream board with FL1/FL2 mask correction

koyomi-lvds-hat.kicad_pro KiCad project configuration and board setup

fabrication-approval.json Machine-readable fabrication and purchasing gates

reports/ DRC, ERC, interface, assembly and sourcing audits

Bill of materials

Parts required for assembly

Grouped component lines from the committed R2.7 manufacturing package. Purchasing blockers are highlighted.

12Line items

23Fitted parts

TopAssembly side

2Sourcing blockers

Part / value	Designators	Package	JLCPCB part	Status
1 µF	C1, C4	0603	`C1592`	Ready
100 nF	C2, C5	0603	`C1591`	Ready
10 nF	C3, C6	0603	`C1589`	Ready
4.7 µF	C7, C8	0603	`C1705`	Ready
DLP2ADN121HL4L	FL1, FL2	Murata DLP2ADN	`C710576`	Source part
SN75LVDS83B	IC1	TSSOP-56	`C35164`	Ready
I-PEX 20374-R30E-31	J2	I-PEX 30-pin	`C5311655`	Source part
Hirose FH12-12S-0.5SH	JBL1	FFC 12-pin	`C88360`	Ready
Hirose FH41-40S-0.5SH	JFFC1	FFC 40-pin	`C596805`	Ready
4.7 kΩ	R1, R2	0603	`C844791`	Ready
47 Ω array	RN1–RN6	4×0603 array	`C425204`	Ready
AP2114H-2.5	U1	SOT-223-3	`C460313`	Ready

Purchasing gate

C5311655 requires pre-order and C710576 requires consignment. Electrical and placement checks already pass.

README

Project Koyomi — display testing HAT

A tested Raspberry Pi HAT for driving the Sony VAIO P display through the Pi's DPI interface and a Texas Instruments SN75LVDS83B LVDS transmitter.

The Toshiba LT080EE04100 panel has no backlight driver, so Koyomi breaks out its backlight connections for external driver development.

TensorFleet's copy adds the missing F.Mask apertures to both DLP2ADN121HL4L filters. The change creates exactly 16 solder-mask openings that KiCad DRC did not flag as missing.

The compact R2.7 variant keeps the same electrical interface and 23-part fitted set in a 29.33% smaller four-layer board.

Raspberry Pi display configuration


                  dtoverlay=vc4-kms-dpi-generic
dtparam=hactive=1600,hfp=32,hsync=65,hbp=97
dtparam=vactive=768,vfp=1,vsync=1,vbp=8
dtparam=clock-frequency=83600000,rgb666
dtoverlay=i2c-gpio,i2c_gpio_sda=23,i2c_gpio_scl=24

Release readiness R2.7 fabrication candidate

✓

Fabrication approvedPrototype gate passed

✓ DRC errors 0

✓ ERC errors 0

✓ Unconnected pads 0

✓ Interface audit 11 nets pass

✓ Fabrication Approved

! Purchase Parts blocked

Board properties

Board: 58.0 x 22.2 mm base
Copper: 4 layers
Finish: ENIG
Minimum via: 0.20 mm
Assembly: Top-side Economic PCBA
Mating system: CM5 carrier B2.2

Hardware revisions

Fabrication ready R2.7 compact RGB A 29.33% smaller, fully routed four-layer prototype with zero DRC/ERC errors and a reproducible JLCPCB package. Purchase remains gated by parts sourcing. Production baseline R2.6 compact RGB The 65.0 x 28.25 mm electrically complete baseline with single-side assembly, audited interfaces and checksumed manufacturing outputs. Tested upstream Original HAT The working Raspberry Pi HAT design with the TensorFleet FL1/FL2 solder-mask correction applied to its canonical KiCad source.

Source of truth

Values shown here come from the committed R2.7 approval, assembly and interface reports.

Inspect reports ↗