TC1724 Datasheet, PDF (76/134 Pages) Infineon Technologies AG – 32-Bit Single-Chip Microcontroller

TC1724
Electrical Parameters
2) Applies to AINx, when used as auxiliary reference input.
3) This represents an equivalent switched capacitance. This capacitance is not switched to the reference voltage
at once. Instead smaller capacitances are successively switched to the reference voltage.
4) The sum of DNL/INL/GAIN/OFF errors does not exceed the related TUE total unadjusted error.
5) If the analog reference voltage range is below V_DDM but still in the defined range of V_DDM / 2 and V_DDM is used,
then the ADC converter errors increase. If the reference voltage is reduced by the factor k (k<1),
TUE,DNL,INL,Gain, and Offset errors increase also by the factor 1/k.
6) If a reduced analog reference voltage between 1V and V_DDM / 2 is used, then there are additonal decrease in
the ADC speed and accuracy.
7) If the analog reference voltage is > V_DDM, then the ADC converter errors increase.
8) For 10-bit conversions the error value must be multiplied with a factor 0.25.
9) For 8-bit conversions the error value must be multiplied with a factor 0.0625.
10) If the alternate reference is used, or f_ADCI is more than 16 MHz, or STC is lower than 8, the accuracy of the ADC
may decrease.
11) Q_CONV is calculated as Q_CONV = C_AREF*V_AREF. The Qconv can be calculated according to this formula.
12) The leakage current definition is a continous function,as shown in figure ADCx Analoge Input Leakage. The
numerical values defined determine the characteristic points of the given countinuous linear approximation -
they do not define step function.
13) The broken wire detection delay against V_AGND is measured in numbers of consecutive precharge cycles at a
conversion rate of not more than 250μs. Results below 10% (199_H).
14) The broken wire detection delay against V_AREF is measured in numbers of consecutive precharge cycles at a
conversion rate of not more than 10μs. This function is influenced by leakage current, in particular at high
temperature.Results above 60% (999_H).
15) Measured without noise.
16) For 10-bit conversion the TUE is ±2LSB; for 8-bit conversion the TUE is ±1LSB
17) A running conversion may become inexact in case of violating the normal conditions (voltage overshoot).
18) If the reference voltage V_AREF increase or the V_DDM decrease, so that V_AREF = (V_DDM + 0.05V to V_DDM + 0.07V),
then the accuracy of the ADC decrease by 4LSB12.
Table 24 Conversion Time (Operating Conditions apply)
Parameter
Symbol Values
Unit Note
Conversion
t_C
time with
post-calibration
Conversion
time without
post-calibration
CC 2 × T_ADC + (4 + STC + n) × T_ADCI μs
2 × T_ADC + (2 + STC + n) × T_ADCI
n = 8, 10, 12 for
n - bit conversion
T_ADC = 1 / f_FPI
T_ADCI = 1 / f_ADCI
Data Sheet
5-31
V1.2, 2014-06