XC2786X Datasheet, PDF (87/120 Pages) Infineon Technologies AG – 16/32-Bit Single-Chip Microcontroller with 32-Bit Performance

XC2786X
XC2000 Family Derivatives
Electrical Parameters
Table 18
A/D Converter Characteristics (cont’d)
(Operating Conditions apply)
Parameter
Switched capacitance
of the reference input
Resistance of
the reference input path
Symbol
Limit Values
Min.
Max.
C_AREFS CC –
7
R_AREF CC –
2
Unit Test
Condition
pF ⁶⁾⁷⁾
kΩ ⁶⁾⁷⁾
1) TUE is tested at V_AREFx = V_DDPA, V_AGND = 0 V. It is verified by design for all other voltages within the defined
voltage range.
The specified TUE is valid only if the absolute sum of input overload currents on Port 5 or Port 15 pins (see
I_OV specification) does not exceed 10 mA, and if V_AREF and V_AGND remain stable during the measurement time.
2) V_AIN may exceed V_AGND or V_AREFx up to the absolute maximum ratings. However, the conversion result in these
cases will be X000_H or X3FF_H, respectively.
3) The limit values for f_ADCI must not be exceeded when selecting the peripheral frequency and the prescaler
setting.
4) This parameter includes the sample time (also the additional sample time specified by STC), the time to
determine the digital result and the time to load the result register with the conversion result.
Values for the basic clock t_ADCI depend on programming and are found in Table 19.
5) The total unadjusted error TUE is the maximum deviation from the ideal ADC transfer curve, not the sum of
individual errors.
All error specifications are based on measurement methods standardized by IEEE 1241.2000.
6) Not subject to production test - verified by design/characterization.
7) These parameter values cover the complete operating range. Under relaxed operating conditions
(temperature, supply voltage) typical values can be used for calculation. At room temperature and nominal
supply voltage the following typical values can be used:
C_AINTtyp = 12 pF, C_AINStyp = 5 pF, R_AINtyp = 1.0 kΩ, C_AREFTtyp = 15 pF, C_AREFStyp = 10 pF, R_AREFtyp = 1.0 kΩ.
V _AIN
R_Source
C _Ext
R_{AIN, On}
A/D Converter
C _AINT ^- C _AINS
C_AINS
Figure 15 Equivalent Circuitry for Analog Inputs
Data Sheet
85
MCS05570
V2.1, 2008-08