2 layers364 × 203 mm
2 layers93.7 × 98.4 mm
Cmii
dbalsom/et20001Resources related to the Tseng Labs ET2000 EGA chipset
- Size
- 93.7 × 98.4 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 33
- Nets
- 82
- Pads
- 295
- Tracks, vias
- 1,339, 85
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 22 Jan 2026
- Updated
- 27 Jan 2026
Overview
Cmii is an open-source printed circuit board by dbalsom, from the dbalsom/et2000 repository on GitHub, published under the MIT licence. It is a 2-layer board of 93.7 × 98.4 mm with 33 parts on 82 nets, routed with 1,339 tracks and 85 vias.
It is built around the 74LS373SC, 74LS240DC and 74LS74PC, with the 74LS02PC, 74LS139PC and 74LS20P-E among its other parts. Its parts include 15 capacitors, 11 ICs, 2 resistors and 1 connector.
Main components
6
74LS373SC
--55℃~+125℃ 1 2.6mA 24mA 38ns@5V,150pF 4.75V~5.25V 74LS 8 Output enable Tri-State - Buffers, Drivers, Receivers, Transceivers ROHSTexas InstrumentsBuffers, Drivers, Receivers, Transceivers74LS240DC
--55℃~+125℃ 1 15mA 18ns@5V,45pF 24mA 29mA 4.75V~5.25V 74LS Output enable Schmitt trigger Tri-State - Buffers, Drivers, Receivers, TransceiversTexas InstrumentsBuffers, Drivers, Receivers, Transceivers
74LS74PC
DIP-140ns 0℃~+70℃ 1 2 20MHz 3.5pF 35ns@5V,50pF 4.5ns 4.75V~5.25V 400uA 74LS Series 8mA 8mA Asynchronous Complementary D-Type Rising Edge Set and Reset DIP-14 Flip FlopsTexas InstrumentsFlip Flops74LS02PC
DIP-140℃~+70℃ 15ns@5V,15pF 2 2.7V 2V 4 4.75V~5.25V 400uA 500mV 74LS 800mV 8mA 8mA NOR Gate DIP-14 Logic Gates ROHSonsemiLogic Gates
74LS139PC
PDIP-1622ns 74LS 8mA Decoder Single Supply PDIP-16 Signal Switches, Multiplexers, DecodersonsemiSignal Switches, Multiplexers, Decoders74LS20P-E
DIP-14-20℃~+75℃ 15ns@5V,15pF 2 2.7V 2V 4 4.75V~5.25V 400mV、500mV 400uA 74LS 800mV 8mA NAND Gate DIP-14 Logic Gates ROHSRenesas ElectronicsLogic Gates
Parts
33| Qty | Value | Footprint | References |
|---|---|---|---|
| 12 | 0.1uF | Capacitor_THT:C_Axial_L3.8mm_D2.6mm_P7.50mm_Horizontal | C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12 |
| 3 | 74LS74 | Package_DIP:DIP-14_W7.62mm | U9, U10, U11 |
| 2 | 22uF | Capacitor_THT:C_Disc_D4.3mm_W1.9mm_P5.00mm | C13, C14 |
| 2 | 74LS373 | Package_DIP:DIP-20_W7.62mm | U7, U8 |
| 2 | R | Resistor_THT:R_Axial_DIN0309_L9.0mm_D3.2mm_P12.70mm_Horizontal | R1, R2 |
| 1 | 6116-15 | Package_DIP:DIP-24_18.0mmx34.29mm_W15.24mm | U2 |
| 1 | 74LS02 | Package_DIP:DIP-14_W7.62mm | U4 |
| 1 | 74LS139 | Package_DIP:DIP-16_W7.62mm | U5 |
| 1 | 74LS20 | Package_DIP:DIP-14_W7.62mm | U6 |
| 1 | 74LS240 | Package_DIP:DIP-20_W7.62mm | U3 |
| 1 | C_Small | Capacitor_THT:C_Axial_L3.8mm_D2.6mm_P7.50mm_Horizontal | C15 |
| 1 | Conn_02x20_Odd_Even | Connector_PinHeader_2.54mm:PinHeader_2x20_P2.54mm_Vertical | J1 |
| 1 | R_Network07 | Resistor_THT:R_Array_SIP8 | RN1 |
| 1 | Z084000xP | Package_DIP:DIP-40_W15.24mm | U1 |
The 30 most common of 33 parts.
Questions
How big is the Cmii PCB?
It measures 93.7 × 98.4 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Cmii use?
33 parts, built around the 74LS373SC, 74LS240DC, 74LS74PC and 74LS02PC. 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 Cmii KiCad files?
From the dbalsom/et2000 repository on GitHub, at the commit this page was made from: the board is cmii/kicad/cmii.kicad_pcb and its schematic cmii/kicad/cmii.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Cmii design in my own project?
Its repository publishes it under the MIT licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
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