Phone Connector (audio) - Configurations and Schematic Symbols

Configurations and Schematic Symbols

These examples are meant to illustrate each possible component of such jacks, but many other configurations using these basic components are available. All examples in the above figure are oriented so the plug 'enters' from the right.

A. A two-conductor TS phone connector. The connection to the sleeve is the rectangle towards the right, and the connection to the tip is the line with the notch. Wiring connections are illustrated as white circles.

B. A three-conductor TRS phone connector. The upper connector is the tip, as it is farther away from the sleeve. The sleeve is shown connected directly to the chassis, a very common configuration. This is the typical configuration for a balanced connection. Some jacks have metal mounting connections (which would make this connection) and some have plastic, to isolate the sleeve from the chassis, and provide a separate sleeve connection point, as in A.

C. This three-conductor jack has two isolated SPDT switches. They are activated by a plug going into the jack, which disconnects one throw and connects the other. The white arrowheads indicate a mechanical connection, while the black arrowheads indicate an electrical connection. This would be useful for a device that turns on when a plug is inserted, and off otherwise, with the power routed through the switches.

D. This three-conductor jack has two normally closed switches connected to the contacts themselves. This would be useful for a patch point, for instance, or for allowing another signal to feed the line until a plug is inserted. The switches open when a plug is inserted. A common use for this style of connector is a stereo headphone jack that shuts off the default output (speakers) when the connector is plugged in.

The most common circuit configurations are the simple mono and stereo jacks (A and B above), however there are a great number of variants manufactured.