4KFPGA PCBHoward + Zitong · engineering review
ACTIVE BOARD SELECTIONXC7A25T-2CSG325I · three separate FPGA PCBs

The 50T material below is an earlier review. See the selected 25T placement and its current three-cable interface.

Open current 25T board ↗

Historical PCB checkpoint · 28 September 2026

Earlier 50T micro-HDMI board

This XC7A50T eight-layer review preserves the earlier headstage placement and per-board component candidates. The selected device is now XC7A25T-2CSG325I; open the current 25T board section ↗.

Historical unrouted reviewSuperseded device and DF40 interface · not for fabrication or purchase

01 / Historical native design

Earlier 50T board

The viewer reads the 28 September KiCad PCB. Switch between copper layers and footprints, or open the 3D export. This is placement and connection evidence, not a routed board.

XC7A50T-CSG325 · 36 × 38 mm
Eight copper layers · 0 tracks · 625 native ratsnest links*Open full native viewer ↗
Step14 board-scale proposal assigning 116 ASIC source balls to L1, L3 and L6, with J5 southwest and J7 northeast.
Step14 layer escape proposal. The colored assignments show no routed copper. The 44 north/south and 77 east/west opposite-half counts are route-feasibility warnings, not trace crossings. See the contact map ↗

02 / Purchasing draft

Fitted parts to source

Quantities are per one 50T FPGA PCB. Rows group identical CAD values, manufacturer codes and footprints. A candidate code still needs engineering and stock checks; “TBD” means the exact ordering part is unresolved.

—grouped part lines
—fitted PCB references
0schematic DNP items excluded
FunctionCAD part / valueQtyReferencesPurchase status / engineering itemPart source
XC7A50T FPGAXC7A50T-CSG325; speed/temperature grade TBDXC7A50T-CSG3251U1Exact code TBDSelect and qualify the full speed and temperature suffix.Source ↗
GTP MGTAVCC regulator; GTP MGTAVTT regulator; power_asic; power_aux; power_coreTPS62135RGXRTPS62135RGXR5U2; U3; U4; U5; U7Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Single-image configuration flashMX25U3232FZBI02MX25U3232FZBI021U6Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Configuration level translatorTXU0304RUTRTXU0304RUTR1U8Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Configuration rail supervisorTLV803EA17DPWRTLV803EA17DPWR1U9Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Custom micro-HDMI cable interface467651001CUSTOM 12 V + JTAG + GTP1J4Electrical review pending12 V is selected for this custom cable, but the proposed R3 interposer has no implemented power path. Qualify the total load, cable/contact current, protection, return path and receiver before applying power.Source ↗
Two 60-contact ASIC mezzanine receptaclesDF40TC-60DS-0.4V(51)DF40TC-60DS-0.4V(51)2J5; J7Mechanical approval pendingTwo rigid DF40T pairs need spacing, alignment and mate review before ordering.Source ↗
GTP power reviewTBD - 2.54mm 2-pin header and removable shuntINIT_B HOLD - shunt before power1J6Exact code TBDSelect and verify an exact ordering part before purchase.Manufacturer source TBD
125 MHz LVDS GTP reference candidateSiT9396AA-02A3-1800-125.000000SiT9396AA-02A3-1800-125.0000001Y2Candidate exact codeVerify 125 MHz phase noise, 1.8 V rail noise and GTP input timing before ordering.Source ↗
Red input-present test LEDAPTD1608LSURCKRED INPUT PRESENT1D1Candidate exact codeRaw input indication only; confirm supply voltage, current, brightness and polarity.Source ↗
Green FPGA-DONE test LEDAPTD1608LZGCKGREEN FPGA DONE1D2Candidate exact codeDONE indication only; verify Q1 drive, current, brightness and polarity.Source ↗
GTP power review; power_asic; power_aux; power_cfg; power_coreXFL4020-102MEC1uH 5.4A Isat30%5L1; L2; L3; L4; L5Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP power reviewMPZ2012S300AT00030R@100MHz / DCR<=10m2FB1; FB2Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
power_inputMSAST32MAB5476MPNDT147u 25V X5R1C1Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP power review; power_asic; power_aux; power_cfg; power_core; power_inputGRM188R72A104KA35D100n 100V X7R6C2; C4; C8; C12; C16; C125Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP power review; power_asic; power_aux; power_cfg; power_coreMSAST31LBB5226MTNA0122u 25V X5R5C3; C7; C11; C15; C124Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP power review; power_asic; power_aux; power_cfg; power_coreEMK212BBJ226MG-T22u 16V X5R5C5; C9; C13; C17; C126Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP power review; power_asic; power_aux; power_cfg; power_coreGRM188R71H103KA01D10n 50V X7R5C6; C10; C14; C18; C127Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
decoupling_coreETPE330M9GB330u 2.5V POSCAP ESR9m@300kHz1C20Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
decoupling_bramGRM32ER60J107ME20L100u 6.3V X5R1C21Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP local bypass; decoupling_aux; decoupling_bank14; decoupling_bank15; decoupling_bank34; decoupling_bank35; decoupling_coreGRM21BR71A475KA73L4.7u 10V X7R18C22; C23; C24; C25; C26; C27; C41; C42; C51; C52; C64; C65; C70; C71; C76; C77; C128; C131Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
decoupling_aux; decoupling_bank14; decoupling_bank15; decoupling_bank34; decoupling_bank35; decoupling_bram; decoupling_coreGRT155R71A474KE01D470n 10V X7R30C28; C29; C30; C31; C32; C33; C34; C35; C36; C37; C43; C44; C45; C46; C53; C54; C55; C56; C66; C67; C68; C69; C72; C73; C74; C75; C78; C79; C80; C81Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
decoupling_asic_bulk; decoupling_aux; decoupling_bank0; decoupling_bank14_bulkGRM32ER70J476ME20L47u 6.3V X7R4C40; C50; C82; C92Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP local bypass; decoupling_xadcGRT155R71C104KE01D100n 16V X7R5C90; C129; C130; C132; C133Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
decoupling_xadcGRM188R71A105KA61D1u 10V X7R1C91Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Boot flash; Reference clockGRM155R71C104KA88D100n4C100; C134; C135; C136Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Boot flashGRM155R61C105KA12D1u 16V X5R1C101Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Boot flash; Reference clockGRM155R71C104KA88D100n 16V X7R11C137; C138; C139; C140; C141; C142; C143; C144; C145; C146; C147Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP reference oscillator supply bypassGRM188R61A106MAALD10u 10V X5R1C148Candidate exact codeCheck effective capacitance at bias and placement beside Y2.Source ↗
power_coreTNPW060332K4BEEA32.4k 0.1%1R1Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
power_asic; power_aux; power_coreTNPW060369K8BEEA69.8k 0.1%3R2; R4; R8Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
power_auxTNPW0603110KBEEA110k 0.1%1R3Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP voltage feedbackTBD - exact 0603 0.1% <=25ppm/K ordering code5.05k 0.1%1R5Exact code TBDSelect and verify an exact ordering part before purchase.Source ↗
GTP voltage feedbackTBD - exact 0603 0.1% <=25ppm/K ordering code6.98k 0.1%2R6; R125Exact code TBDSelect and verify an exact ordering part before purchase.Source ↗
power_asicTNPW060380K6BEEA80.6k 0.1%1R7Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
power_coreWSLP1206R0120FEA12m 1% 1W1R9Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP power review; power_aux; power_coreCRCW0603100KFKEA100k4R10; R11; R126; R127Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Boot flashCRCW04022K40FKED2.4k1R100Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Boot flash; Programming JTAGCRCW04024K70FKED4.7k6R101; R102; R108; R109; R110; R128Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Programming JTAGCRCW040233R0FKED332R103; R118Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Programming JTAGCRCW04021K00FKED1k2R111; R114Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
Programming JTAGCRCW040210K0FKED10k4R115; R116; R117; R129Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
power_aux_bulk_isolationWSLP1206R0150FEA15m 1% 1W1R122Candidate exact codeCheck the exact ordering suffix, supplier stock and electrical fit before purchase.Source ↗
GTP reference resistorTBD 100 ohm 1% 0402100R 1%1R123Exact code TBDSelect and verify an exact ordering part before purchase.Source ↗
GTP voltage feedbackTBD - exact 0603 0.1% <=25ppm/K ordering code3.10k 0.1%1R124Exact code TBDSelect and verify an exact ordering part before purchase.Source ↗
Separate test-LED current limitsCRCW06033K30FKEA3.3k2R130; R131Candidate exact codeCurrent and power depend on the unresolved cable input voltage.Source ↗
FPGA-DONE switch gate pull-downCRCW0402470KFKED470k1R132Candidate exact codeCheck Q1 default-off behavior and DONE startup timing.Source ↗
FPGA-DONE LED low-side switchDMN52D0U-7DMN52D0U1Q1Candidate exact codeVerify 1.8 V gate drive and LED turn-on margin on the bench.Source ↗

This table is generated from the compact native schematic and checked against PCB references. Copper-only pads and 0 DNP schematic items are excluded. No components or boards have been ordered.

03 / Beyond this PCB

System items still needed

These items are outside the fitted FPGA PCB BOM. Known prototype quantities are shown; unresolved selections and quantities stay TBD.

Additional itemQuantity Current candidateWhat must be settled
Routing-board mating plugs2Hirose DF40TC-60DP-0.4V(51)Pair with J5/J7 receptacles; rigid-board spacing, alignment and assembly approval pending. Source ↗
Routing-board PCB and ASICs1 routing board; 8 ASICs proposed; spares TBDMatching routing design and ASIC ordering code TBDThe FPGA board BOM cannot specify the ASIC or routing-board parts; obtain the carrier design and approved ASIC code. Source ↗
Custom micro-HDMI cable and strain relief1 cable set; spares TBDCustom 19-contact wiring, not standard HDMIConfirm 3 TX/1 RX channel map, shield, length, supply voltage, contact current and 100% continuity test.
µHDMI pass-through interposer / downstream interface1 proposed prototype; electronics TBDR3 XEM8310 ↔ BRK8310 interposer candidateConfirm GTY clock/IP, selective MC3 routing, BRK J6 pass-through, cable, protection, power and physical fit; there is no interposer PCB. Current plan ↗
JTAG programmer and voltage adapter1 tool set1.8 V compatible JTAG candidateSelect exact probe, keyed adapter and bring-up cable; confirm I/O voltage before use.
Edge I/O test fixture and J6 shunt1 fixture; 1 shunt; spares TBD1.5 V compatible probes, ground return and keyed INIT_B jumperMatch the final edge-pad pitch and J6 header before ordering; fixture and jumper are outside the fitted PCB BOM.
Routing-board ASIC LDO power feedTBDSeparate supply/return path and routing-board rail partsNo DF40T supply contacts are spare. Select feed hardware, LDOs and protection after load budgets; J4.19 0.8 A is only a contact rating. Source ↗
Input supply and protection1 source; protection BOM TBD12 V selected; connector protection, current limiting and backfeed control TBDThe 12 V route is not implemented or load-qualified. Verify total FPGA plus ASIC load, inrush, cable loss and startup sequence. Source ↗
PCB fabrication and assembly1 prototype lot; spares TBDEight-layer board, stencil and assemblyFabricator stackup, controlled impedance, via process, thermal and assembly reviews pending.

The FPGA and all fitted on-board flash, clock, LEDs and passives are counted above in the native per-board table. All rows here are system planning items, not a purchase authorization. Download system CSV ↓ · JSON ↓

04 / Before ordering

Resolve the design choices

The 50T board is useful for review now. These items determine whether its candidates can become an orderable BOM.

  1. Complete the selected 12 V power contract. Establish the FPGA plus ASIC load and routing-board feed, then design the protected source, cable and rail calculations together.
  2. Close connector identities. Approve both DF40T mating pairs, their spacing and alignment, plus J4 and the custom cable drawing.
  3. Approve FPGA and passive order codes. Select the complete XC7A50T suffix and exact codes for every TBD line.
  4. Complete the GTP/GTY design. The 3-TX/1-RX contact mapping is selected; verify reference clock, XEM GTY implementation, cable polarity, coupling and ESD, then route and check the PCB.
  5. Qualify manufacturing and power. Close ERC/DRC, current and thermal budgets, startup and shutdown, measurements at the FPGA pins, cable tests and supplier stackup.

05 / Source files

Review the evidence

Open the complete project with its local libraries and hierarchical sheets. The PDF and validation records match this dated unrouted revision.

The web ZIP is a 68-file portable derivative of the 69-file local Step15 project: only optional KiCad .kicad_prl UI preferences are omitted, and all other project-file hashes match. Read the package provenance ↗