How it works

The PL2303 bridges USB communication and an asynchronous serial interface. A complete RS-232 connection must also provide the appropriate electrical signaling and connector wiring shown in the schematic.

USB, logic-level UART, and RS-232 are different electrical interfaces. Check the exact PL2303 variant and any level-shifting components rather than assuming the pins can be wired directly to another serial device.

Original schematic

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Figure 1 · NewCircuits archive · Download image ↓

On the bench

Use the driver supported by the actual chip revision and operating system. Verify connector pinout, signal direction, and ground continuity before connecting external equipment.

Resources & provenance

Rewritten from the original circuits/pcr/s40mn76_pcr002.php page. Component values and historical performance claims have not been independently bench-tested. The circuit figures have had their watermarks removed.

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