Bill of materials
I’m not expecting anyone to actually want to build this as a complete development board but just in case, here’s the full bill of materials.
| Identifiers | Value | Quantity | Description | Footprint |
|---|---|---|---|---|
| C1, C2, C3, C4, C5, C6, C7, C53, C54, C55, C56, C57 | 2.2µ | 12 | Ceramic capacitor | 0402 |
| C8, C14, C15, C16, C17, C18, C19, C20, C21, C22, C23, C24, C25, C26, C45, C46, C47, C48, C49, C50, C51, C52 | 470n | 22 | Ceramic capacitor | 0402 |
| C9, C10, C11, C12, C13, C27, C28, C29, C30, C31, C32, C33, C34, C35, C36, C37, C38, C39, C40, C41, C42, C43, C44, C58, C59, C60, C61, C62, C63, C64, C65, C66, C67, C68, C69, C70, C71, C72 | 47n | 38 | Ceramic capacitor | 0402 |
| C73 | 15p 5% | 1 | Ceramic capacitor | 0603 |
| C74, C81, C82, C83, C84 | 22µ | 5 | Ceramic capacitor | 0805 |
| C75 | 470n | 1 | Ceramic capacitor | 0603 |
| C76, C78 | 10µ | 2 | Ceramic capacitor | 0805 |
| C77 | 8200p | 1 | Ceramic capacitor | 0603 |
| C79, C80, C85, C86, C87, C88 | 100n | 6 | Ceramic capacitor | 0603 |
| C89, C90 | 470µ | 2 | Electrolytic capacitor | Radial 4x8x12mm |
| D1 | Schottky | 1 | ST Micro STPS3L40S | DO-214AB |
| D2 | red LED | 1 | Power LED | 0603 |
| D3, D4, D5, D6, D7 | red LED | 5 | Indicator LEDs | 2012 |
| L1, L2 | 3.3µ | 2 | LQH44PN3R3MP0L | 4x4mm |
| P1 | GPIO Header 39×3 | 1 | 39×3 pin header | 2.54mm |
| P2 | GPIO Header 28×2 | 1 | 28×2 pin header | 2.54mm |
| P3 | USB mini B | 1 | USB power entry | SMD |
| P4 | Header 1×4 | 1 | 1.8V power header | 2.54mm |
| P5 | Header 1×2 | 1 | GCK2 input | 2.54mm |
| P6 | Header 1×2 | 1 | 50MHz oscillator enable | 2.54mm |
| P7 | Header 2×6 | 1 | CLK/MODE header | 2.54mm |
| P8 | Header 1×5 | 1 | PROG header | 2.54mm |
| P9 | Header 2×7 | 1 | JTAG IDC boxed header | 2.54mm |
| P10 | Header 2×2 | 1 | 3.3V power header | 2.54mm |
| P11 | Header 1×4 | 1 | 5V power header | 2.54mm |
| R1 | 27k 1% | 1 | SMD resistor | 0603 |
| R2 | 100k | 1 | 0603 | |
| R3 | 20k 1% | 1 | 0603 | |
| R4 | 45.3k | 1 | 0603 | |
| R5, R7, R8, R9, R10, R11, R12, R13 | 10k | 8 | 0603 | |
| R6, R14, R15, R16, R17, R18 | 390 | 6 | 0805 | |
| R19, R20, R22, R23, R24, R25, R26, R27, R30, R31, R32, R33, R34, R37, R38, R39, R40, R41, R42, R43 | 100 | 20 | 0402 | |
| R21, R28, R29, R35, R36 | 187 | 5 | 0402 | |
| SW1 | Button | 1 | PCB mount button | through hole |
| U1 | XCV600e FPGA | 1 | Xilinx Virtex-e | FG676 BGA |
| U2 | LMR10515 | 1 | TI switching regulator | SOT23-5 |
| U3 | TPS54339DDA | 1 | TI switching regulator | SO-8 powerpad |
| U4 | S25FL127S | 1 | Spansion 128Mb flash | SO-8 (208mil) |
| U5 | MT48LC16M16A2P-6A | 1 | Micron SDRAM | TSOP2-54 |
| U6 | IS61LV5128AL | 1 | ISSI 512Kb SRAM | TSOP2-44 |
| X1 | ASE-50.000MHZ-LR-T | 1 | Abracon 50MHz oscillator | 3.2×2.5mm |
PCB Design and Layout
I stated earlier that I would be constraining the board size to 10x10cm so that I can qualify for an affordable prototype four layer service. The next decision to make is the layer stackup.
I went for a commonly used arrangement of signal – ground – power/signal – signal. Having a ground plane directly below the top means that I can do impedance controlled routing on the top layer with traces that don’t have to be very wide. All the differential pairs are set to the correct 12.3 mil width for 50Ω impedance control on this board.
