What is the difference between a 3.5mm and a 2.5mm interface headset?

• Double poles for single mic connectors, or mono connectors
• Three-pole for two-channel connectors
• Four-pole for the connector with MIC function and two-channel output

The 2.5mm PIN definition and function division is the same as 3.5mm, just a small diameter.

One, 3.5mm/2.5mm headphone plug Comparison

As the following figure shows, the difference between the two is the plug diameter, now 3.5MM is most commonly used.

Second, 3.5MM headphone plug definition

The 3.5MM plug is defined as the following figure (image source at the end of the address), please note that the iphone and Nokia Mic/gnd two locations in reverse. Therefore, you need to pay attention to the PIN definition in order to purchase the wiring or use it on a non original occasion.

Ordinary mobile phone headset, just add a two of the adapter, you can insert a computer notebook to use, environmental protection, no need for another computer headset.

Just look at the definition of the pin above (summarize so much and then refine it later):

• Four-pole plug into the three-pole seat-because the socket is a single contact, so mic circuit breaker, headphones can be used normally
• Two-pole plug into a single pole seat-single channel effective, another channel is open
• Two-pole plug into level three--leads to a channel short circuit
• Two-pole plug inserts a--mic and a channel short circuit
• Three-pole plug inserted into quadrupole--mic input short Circuit

So, in principle, do not go into the mix, although these low power low voltage connections generally will not burn the device