US Patent 10282579 Initiating fingerprint capture with a touch screen

A method for initiating fingerprint capture in an electronic device is described. The device includes a touch screen with a sensing region, a touch controller, a fingerprint controller, and a host. The device is placed in a low power doze mode where the fingerprint controller is in a low power state and the device scans for an object proximate to the sensing region. When an object is proximate to the sensing region, the device executes a validation mode to determine whether the object is a fingerprint. When a fingerprint is detected, the device sends a wake up signal to the fingerprint controller and places the fingerprint controller in a high power mode. One or more fingerprint images are then captured.