MC9S12KG128 Datasheet, PDF (573/600 Pages) Freescale Semiconductor, Inc – Microcontrollers

Appendix A Electrical Characteristics
A.5 ATD Characteristics
This section describes the characteristics of the analog to digital converter.
A.5.1 ATD Operating Characteristics
The Table A-11 shows conditions under which the ATD operates.
The following constraints exist to obtain full-scale, full range results:
VSSA ≤ VRL ≤ VIN ≤ VRH ≤ VDDA. This constraint exists since the sample buffer amplifier can not
drive beyond the power supply levels that it ties to. If the input level goes outside of this range it will
effectively be clipped.
Table A-11. 5V ATD Operating Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
Rating
Symbol
Min
Typ
Max
Unit
1 D Reference Potential
2 C Differential Reference Voltage¹
Low VRL
VSSA
—
VDDA/2
V
High VRH
VDDA/2
—
VDDA
V
VRH-VRL
4.75
5.0
5.25
V
3 D ATD Clock Frequency
f_ATDCLK
0.5
—
2.0
MHz
4 D ATD 10-Bit Conversion Period
Clock Cycles² N_CONV10
14
—
28
Cycles
Conv, Time at 2.0MHz ATD Clock f_ATDCLK T_CONV10
7
—
14
µs
Conv, Time at 4.0MHz³ ATD Clock f_ATDCLK T_CONV10
3.5
—
7
µs
5 D ATD 8-Bit Conversion Period
Clock Cycles¹ N_CONV8
12
—
26
Cycles
Conv, Time at 2.0MHz ATD Clock f_ATDCLK T_CONV8
6
—
13
µs
6 D Stop Recovery Time (V_DDA=5.0 Volts)
t_SR
—
—
20
µs
7 P Reference Supply current (two ATD modules)
I_REF
—
—
0.750
mA
8 P Reference Supply current (one ATD module)
I_REF
—
—
0.375
mA
1 _{Full accuracy is not guaranteed when differential voltage is less than 4.75V}
2 _{The minimum time assumes a final sample period of 2 ATD clocks cycles while the maximum time assumes a final sample}
period of 16 ATD clocks.
3 _{Reduced accuracy see Table A-14 and Table A-15.}
MC9S12KG128 Data Sheet, Rev. 1.15
Freescale Semiconductor
573