Tool/software:
Referring to the TPS1663 data sheet, section 7.3, The resistance for PLIM is limited to the range of 60.4 to 150 kOhm.
The set value for the power limit is given by PLIM (W) = R.PLIM (Kohm). (Equation 5 in section 9.3.5 of data sheet)
This limits the lower-end of the use of PLIM to 60.4 Watts (nominal).
Figure 7-7 indicates that for power limiting above 100 W, the percent accuracy is 6% and between 100 and 60 W, the accuracy is changes linearly to 7%. That is, at 100 W, the accuracy is 6%. With a 40W decrease in PLIM to 60 W, the PLIM accuracy becomes worse by 1%
Questions:
- Fig 7-7 implies that the reason for the 60.4kOhm lower limit on R.PLIM is low accuracy. Is this correct?
- If R.PLIM is set to less than 60.4KOhm, does the IC work correctly (albeit with lower accuracy)?
- If R.PLIM were 20 kOhm (That is, the eFuse is set for a power limit of 20 W, which is a 40 W decrease from what is shown in Figure 7-7), would the expected accuracy then be 8%?
