Mapping PS button to PTT?

I use a Dual Shock 3 for my PC. I have the software to run it and it's run smoothly for me for several years. However, I use a Discord server to talk to my friends, and I have auto-mic there so they hear whatever I'm saying, while people in-game don't. But sometimes I need to talk to someone in game that isn't in my group or on my server, and the PS button on my DS3 is the only button that isn't taken up by something important. Is there a way I can map it to in-game PTT?