SLASEE4C January 2018 – December 2019 MSP430FR2512 , MSP430FR2522
PRODUCTION DATA.
Refer to the PDF data sheet for device specific package drawings
To show sensitivity, in terms of farads, the internal reference capacitor is used as the change in capacitance. In the mutual-capacitance case, the 0.1-pF capacitor is used. In the self-capacitance case, the 1-pF reference capacitor is used. For simplicity, the results for only button 1 on both the CAPTIVATE-PHONE and CAPTIVATE-BSWP panels are reported in Table 7-1.
CONVERSION COUNT | CONVERSION GAIN | CAPTIVATE-PHONE BUTTON 1 | CAPTIVATE-BSWP BUTTON 1 | ||
---|---|---|---|---|---|
CONVERSION TIME (µs) | COUNTS FOR 0.1-pF CHANGE | CONVERSION TIME (µs) | COUNTS FOR 1-pF CHANGE | ||
100 | 100 | 25 | 6 | 50 | 8 |
200 | 200 | 50 | 10 | 100 | 16 |
200 | 100 | 50 | 21 | 100 | 31 |
800 | 400 | 200 | 70 | 400 | 112 |
800 | 200 | 200 | 140 | 400 | 202 |
800 | 100 | 200 | 257 | 400 | 333 |
An alternative measure in sensitivity is the ability to resolve capacitance change over a wide range of base capacitance. Table 7-2 shows example conversion times (for a self-mode measurement of discrete capacitors) that can be used to achieve the desired resolution for a given parasitic load capacitance.
CAPACITANCE Cp (pF)(1) | CONVERSION COUNT/GAIN | CONVERSION TIME (µs) | COUNTS FOR 0.130-pF CHANGE | COUNTS FOR 0.260-pF CHANGE | COUNTS FOR 0.520-pF CHANGE |
---|---|---|---|---|---|
23 | 400/100 | 200 | 10 | 23 | 35 |
50 | 550/100 | 275 | 11 | 24 | 37 |
78 | 650/100 | 325 | 11 | 23 | 36 |
150 | 850/100 | 425 | 11 | 22 | 35 |
150(2) | 1200/200 | 600 | 11 | 23 | 37 |
200(2) | 1200/150 | 600 | 13 | 26 | 41 |