PTT is a way of provider TPM, they are not two separate things. PTT is a non-dedicated hardware approach to TPM 2.0. PTT is designed for low power devices, often used in industrial computing.

Traditionally TPM requires a TPM module, a dedicated hardware processor and firmware for security. With TPM 2.0 dedicated hardware is no longer required. PTT is Intel's implementation of TPM 2.0 for low power systems.