Bill of Materials (TTL Buffer Boards) - IanSB/RGBtoHDMI GitHub Wiki

Introduction

This page lists the parts needed by the TTL buffer boards for use with the 6-12 bit boards (by IanB)

These boards are not essential as you can connect directly to the 12 way header on the main board. However they perform two functions:

  1. They buffer the signals and protect the CPLD from damage
  2. They bring their connectors to the outside of the recommended case so that leads for different computers can be easily swapped.

The latest gerbers are here:

images/TTL_interfaces.jpg

3 bit buffer parts

Part Description Supplier Quantity Part Ref Min Order Notes
4K7 0805 Resistor RS 905-2924 4 off R1-4 50 R5 Not fitted
100nf 0805 Multilayer Ceramic Capacitor RS 464‑6688 1 off C1 50 working voltage ≥ 10V
Schottky diode MBR130LSFT1G Farnell 2463407 1 off D1 5 SOD-123FL package
74LS08 TTL Farnell 1287549 1 off U1 1 SOIC package
Samtec SSW-106-02-T-D-RA 2x6 way 0.1" female right angle PCB Header Farnell 2779580 1 off P1 1
Samtec TLW-104-06-T-S 1x4 way male header RS 198-2815 1 off P2 1 Long side of pins goes in PCB
Samtec TLW-101-06-T-S 1x1 way male header RS 198-2806 2 off P6, P7 1 P6 & P7 should be trimmed flush with the plastic to act as support/spacers (see photo)
6 Way IDC header (vertical) Farnell 2215302 1 off P4 10

PC buffer parts

Part Description Supplier Quantity Part Ref Min Order Notes
100nf 0805 Multilayer Ceramic Capacitor RS 464‑6688 1 off C1 50 working voltage ≥ 10V
Bourns 4605X-101-472LF 4K7 x 4 Resistor Network Farnell 9356100 2 off RN1-2 1
74LS245 TTL Farnell 1287549 1 off U1 1 SOIC package
Samtec SSW-106-02-T-D-RA 2x6 way 0.1" female right angle PCB Header Farnell 2779580 1 off P1 1
Samtec TLW-104-06-T-S 1x4 way male header RS 198-2815 1 off P2 1 Long side of pins goes in PCB
Samtec TLW-101-06-T-S 1x1 way male header RS 198-2806 2 off P6, P7 1 P6 & P7 should be trimmed flush with the plastic to act as support/spacers (see photo)
9 way D-sub female Farnell 1084678 1 off P4 5

6 bit buffer parts

Part Description Supplier Quantity Part Ref Min Order Notes
100nf 0805 Multilayer Ceramic Capacitor RS 464‑6688 1 off C1 50 working voltage ≥ 10V
Bourns 4605X-101-472LF 4K7 x 4 Resistor Network Farnell 9356100 2 off RN1-2 1
Schottky diode MBR130LSFT1G Farnell 2463407 1 off D1 5 SOD-123FL package
74LS245 TTL Farnell 1287549 1 off U1 1 SOIC package
Samtec SSW-106-02-T-D-RA 2x6 way 0.1" female right angle PCB Header Farnell 2779580 1 off P1 1
Samtec TLW-104-06-T-S 1x4 way male header RS 198-2815 1 off P2 1 Long side of pins goes in PCB
Samtec TLW-101-06-T-S 1x1 way male header RS 198-2806 2 off P6, P7 1 P6 & P7 should be trimmed flush with the plastic to act as support/spacers (see photo)
10 Way IDC header (vertical) Farnell 2843527 1 off P4 10

8 bit buffer parts

Part Description Supplier Quantity Part Ref Min Order Notes
100nf 0805 Multilayer Ceramic Capacitor RS 464‑6688 2 off C1-2 50 working voltage ≥ 10V
Bourns 4606X-101-472LF 4K7 x 5 Resistor Network Farnell 9356240 2 off RN1-2 1
Schottky diode MBR130LSFT1G Farnell 2463407 1 off D1 5 SOD-123FL package
74LS245 TTL Farnell 1287549 1 off U1 1 SOIC package
74LS08 TTL Farnell 1287549 1 off U2 1 SOIC package
Samtec SSW-106-02-T-D-RA 2x6 way 0.1" female right angle PCB Header Farnell 2779580 1 off P1 1
Samtec TLW-104-06-T-S 1x4 way male header RS 198-2815 1 off P2 1 Long side of pins goes in PCB
Samtec TLW-101-06-T-S 1x1 way male header RS 198-2806 2 off P6, P7 1 P6 & P7 should be trimmed flush with the plastic to act as support/spacers (see photo)
12 Way IDC header (vertical) Farnell 2843528 1 off P4 10

Cable assembly

The cable assembly will vary with each board and will require a matching IDC connector and ribbon cable plus an appropriate connector for the computer. A standard 9 way CGA/EGA/MDA cable should plug into the PC buffer board.

Note after trimming their pins as mentioned above, P6 and P7 act as feet and rest on top of the Pi zero's camera connector to stop P2 on the buffer boards from falling out of its socket if you push down on their external connectors which might result in the bottom of the buffer boards shorting against components on the Pi zero.