
CompaqportableIII
raymondh2/CompaqPortableIII
Current PCB Memory Expansion board layout is untested. The backplane for the expansion cards is tested and working.

The SN75477P is a buffers, Drivers, Receivers, Transceiver made by Texas Instruments in a PDIP-8 package with 8 pins. 0℃~+70℃ 1 100uA 2 300mA 350ns@5V,15pF 4.5V~5.5V TTL-compatible CMOS Unidirectional PDIP-8 Buffers, Drivers, Receivers, Transceivers ROHS.
PCBKit's library has its KiCad symbol (EasyEDA_Cloud:SN75477DE4G4, from EasyEDA) and its footprint (Package_DIP:DIP-8_W8.89mm_SMDSocket_LongPads, from KiCad's library), ready for a KiCad board. 250 are in stock at JLCPCB (part C2859816). 2 open-source boards in 2 repositories on GitHub use it.
| Pin | Name | Type |
|---|---|---|
| 1 | S | Unspecified |
| 2 | 1A | Unspecified |
| 3 | 1Y | Unspecified |
| 4 | GND | Unspecified |
| 5 | CLAMP | Unspecified |
| 6 | 2Y | Unspecified |
| 7 | 2A | Unspecified |
| 8 | VCC | Unspecified |

raymondh2/CompaqPortableIII
Current PCB Memory Expansion board layout is untested. The backplane for the expansion cards is tested and working.

<iframe src="https://pcbkit.io/embed/parts/ti/SN75477P" title="SN75477P in PCBKit" width="100%" height="480" style="border:0;border-radius:12px" allow="fullscreen" loading="lazy"></iframe><img src="https://pcbkit.io/embed/parts/ti/SN75477P.jpg" alt="SN75477P" width="1200" height="900">[](https://pcbkit.io/parts/ti/SN75477P)Yes. The symbol is EasyEDA_Cloud:SN75477DE4G4 and the footprint Package_DIP:DIP-8_W8.89mm_SMDSocket_LongPads, both drawn on this page. PCBKit places them on a board for you when you design with it.
PDIP-8, with 8 pins. Its footprint is drawn on this page.
Texas Instruments publishes it: the Datasheet link on this page opens it.
JLCPCB lists it as part C2859816, with 250 in stock; the sellers' links on this page open their listings.
Parts like it in the library: the SN75451BP by Texas Instruments, the SN75452BP by Texas Instruments, the SN75454BP by Texas Instruments and the SN75462P by Texas Instruments. Check their datasheets: a part that fits the footprint may still differ in its ratings.
2 boards in 2 repositories on GitHub; the most starred are listed on this page, with their KiCad files.