The decoder chip works. It replaces 1/4 of the 74139 for the Z88 design.
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| Part No | Chip | Manufacture | Speed nS | Package | Price | |||
|---|---|---|---|---|---|---|---|---|
| Min | Typ | Max | ||||||
| 1741279 | SN74LVC2G32QDCURQ1 | Ti | <2.5 | SM8 | $ 0.55 | |||
| SN74LVC1G139DCUT Decoder | Ti / Farnell | <2.5 | VSSOP | £0.404 | ||||
SN74LVC2G32DCTR OR Gate | Ti / Farnell | SSOP-8 | £0.377 | |||||
The 2 input positive display or gates fast times.
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Signal lines are used on all 4 layers.
| Power Allocation | |
|---|---|
| top copper | GND |
| inner 1 | GND |
| inner 2 | Vcc |
| bottom | GND |
Things to check
differences between
VSSOP (8)
SM8
SSOP-8
footprint
Provisional Layout
To be updated when completed
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