@@chicken Your high level description of the ESI module is spot on. I will like to add my two cents to the description. Each AFE has two types of inputs (ESICIx and ESICHx), The main difference is that with ESICHx you can excite sensors (AFE1 and AFE2 use the same excitation logic) and ESICIx inputs are not connected to the excitation logic. In addition to ACLK, SMCLK or 32KHz oscillator you can also use ESICLK which has a nominal frequency of 4.8 MHz but can be tunned to operate between 2.3 -7.9 MHz in ~78 KHz increments. Also, the ESI module allows you to divde your low frequency clock source by a wide number of dividers (refer to Table 28-25 in SLAU367) Correct, you can program up to 127 states and the state transition are driven by output of PPU(PPUS1, PPU2,PPUS3) and bit Q6. Note: if you are using PPUS3 and bit Q6 for next PSM state transition you need to properly configure the ESIPSM register for such operation.