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XC2361B Datasheet, PDF (88/128 Pages) Infineon Technologies AG – 16/32-Bit Single-Chip Microcontroller with 32-Bit Performance | |||
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XC2361B, XC2363B, XC2364B, XC2365B
XC2000 Family / Value Line
Electrical Parameters
Sample time and conversion time of the XC236xBâs A/D converters are programmable.
The timing above can be calculated using Table 21.
The limit values for fADCI must not be exceeded when selecting the prescaler value.
Table 21 A/D Converter Computation Table
GLOBCTR.5-0 A/D Converter
INPCRx.7-0
Sample Time1)
(DIVA)
Analog Clock fADCI
(STC)
tS
000000B
fSYS
00H
tADCI Ã 2
000001B
fSYS / 2
01H
tADCI Ã 3
000010B
fSYS / 3
02H
tADCI Ã 4
:
fSYS / (DIVA+1)
:
tADCI Ã (STC+2)
111110B
fSYS / 63
FEH
tADCI Ã 256
111111B
fSYS / 64
FFH
tADCI Ã 257
1) The selected sample time is doubled if broken wire detection is active (due to the presampling phase).
Converter Timing Example A:
Assumptions: fSYS
Analog clock
fADCI
Sample time
tS
Conversion 10-bit:
tC10
Conversion 8-bit:
tC8
= 80 MHz (i.e. tSYS = 12.5 ns), DIVA = 03H, STC = 00H
= fSYS / 4 = 20 MHz, i.e. tADCI = 50 ns
= tADCI Ã 2 = 100 ns
= 13 à tADCI + 2 à tSYS = 13 à 50 ns + 2 à 12.5 ns = 0.675 μs
= 11 à tADCI + 2 à tSYS = 11 à 50 ns + 2 à 12.5 ns = 0.575 μs
Converter Timing Example B:
Assumptions: fSYS
Analog clock
fADCI
Sample time
tS
Conversion 10-bit:
tC10
Conversion 8-bit:
tC8
= 40 MHz (i.e. tSYS = 25 ns), DIVA = 02H, STC = 03H
= fSYS / 3 = 13.3 MHz, i.e. tADCI = 75 ns
= tADCI Ã 5 = 375 ns
= 16 à tADCI + 2 à tSYS = 16 à 75 ns + 2 à 25 ns = 1.25 μs
= 14 à tADCI + 2 à tSYS = 14 à 75 ns + 2 à 25 ns = 1.10 μs
Data Sheet
88
V1.2, 2010-04
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