2 layers99.6 × 99.7 mm
2 layers87.5 × 86.4 mm
Isa post card
ifilot/isa-post-cardISA post card for XT-class systems (8 bit)
- Size
- 87.5 × 86.4 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 37
- Nets
- 130
- Pads
- 302
- Tracks, vias
- 811, 49
- Pours
- 214
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 8 Aug 2025
- Updated
- 29 Sep 2025
Overview
Isa post card is an open-source printed circuit board by ifilot, from the ifilot/isa-post-card repository on GitHub. It is a 2-layer board of 87.5 × 86.4 mm with 37 parts on 130 nets, routed with 811 tracks and 49 vias.
It is built around the 74HCT688D and 74HC00D. Its parts include 8 capacitors, 6 resistors, 6 ICs, 6 diodes and 3 connectors. It belongs with the retro computing and games boards and the FPGA and CPLD boards of this library.
Main components
2README
README.mdISA POST card
8-bit ISA post card for XT-class systems
Parts
37| Qty | Value | Footprint | References |
|---|---|---|---|
| 7 | 100n | Capacitor_THT:C_Disc_D5.0mm_W2.5mm_P5.00mm | C2, C3, C4, C5, C6, C7, C8 |
| 4 | 1k | Resistor_THT:R_Array_SIP8 | RN3, RN4, RN5, RN6 |
| 3 | 1k | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R1, R2, R5 |
| 2 | 10k | Resistor_THT:R_Array_SIP9 | RN1, RN2 |
| 2 | 2.4k | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R3, R4 |
| 2 | 74HCT688 | Package_DIP:DIP-20_W7.62mm_Socket | U1, U2 |
| 2 | D168K | Display_7Segment:D1X8K | U5, U6 |
| 2 | SW_DIP_x05 | Button_Switch_THT:SW_DIP_SPSTx05_Slide_9.78x14.88mm_W7.62mm_P2.54mm | SW1, SW2 |
| 1 | +12V | LED_THT:LED_D5.0mm | D2 |
| 1 | +5V | LED_THT:LED_D5.0mm | D1 |
| 1 | -12V | LED_THT:LED_D5.0mm | D4 |
| 1 | -5V | LED_THT:LED_D5.0mm | D3 |
| 1 | 10u | Capacitor_THT:CP_Radial_D4.0mm_P1.50mm | C1 |
| 1 | 500 | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R6 |
| 1 | 74HC00 | Package_DIP:DIP-14_W7.62mm_Socket | U4 |
| 1 | ATF1504AS-xJx44 | Package_LCC:PLCC-44_THT-Socket | U3 |
| 1 | Bus_ISA_8bit_AB_Rev0 | components:ISA_CARD_EDGE_CONNECTOR_8BIT_Rev1 | J3 |
| 1 | CLK | LED_THT:LED_D5.0mm | D5 |
| 1 | POWER | Connector_PinHeader_2.54mm:PinHeader_1x02_P2.54mm_Vertical | J2 |
| 1 | PROGRAMMER | Connector_IDC:IDC-Header_2x05_P2.54mm_Vertical | J4 |
| 1 | RESET | LED_THT:LED_D5.0mm | D6 |
Questions
How big is the Isa post card PCB?
It measures 87.5 × 86.4 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Isa post card use?
37 parts, built around the 74HCT688D and 74HC00D. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Isa post card KiCad files?
From the ifilot/isa-post-card repository on GitHub, at the commit this page was made from: the board is pcb/isa-post-card.kicad_pcb and its schematic pcb/isa-post-card.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Isa post card design in my own project?
Its repository states no licence, so its author keeps all rights: ask ifilot before reusing the design.
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