iPad mini broken digitizer

There isn't. The Passcode is encrypted on your device and that device only. If you've backed up in the recent past, you'll have to access to that backup when you get your device back. If you haven't ever backed up the device, your data is most assuredly gone.

The time to backup your device to ensure no loss of data is before you have a catastrophic event. If the screen is locked and you can't unlock it, you can't back it up now.