To reach active voltage of touch section of the mobile, a touch regulator ic is available. This regulator ic can be found in many other sections such as the Display Camera section…
- PIN number 4 comes from 3.7v power ic. If this voltage is not available then the touch will not be enabled, if this voltage is not received by checking, Touch will be enabled when placed in direct jumper from vbat.
- Pin number 3 comes from cpu ic to active voltage 1.8v, if active voltage is not found, then it jumper with an active voltage of 1.8 v.
- Output voltage at pin number 1 will be 3.2v. If the signal does not arrive, check the en signal and input voltage if the signal and input voltage is coming, the regulatior may be bad.
Mi Note 3 touch regulator IC
Camera regulator IC