900844 Datasheet, PDF (90/118 Pages) Freescale Semiconductor, Inc – Integrated Power Management IC for Ultra-mobile and Embedded Applications

FUNCTIONAL DEVICE OPERATION
ADC SUBSYSTEM
Table 57. ADC Inputs
Channel SELECT[4:0]
ADC Input Signal
Input Level
Scaling
Scaled Version
8
01000
Reserved
Reserved
Reserved
Reserved
9
01001
Battery Pack Thermistor
0 – 2.4 V
x1
0– 2.4 V
10
01010
General Purpose ADIN10
Touch screen X+
0-200 mV / 0-2.0 V
0 – 1.2
10x / 1x
x2
0 – 2.4 V
0 – 2.4 V
11
01011
General Purpose ADIN11
Touch screen X-
0-200 mV / 0-2.0 V
0 – 1.2
10x / 1x
x2
0 – 2.4 V
0 – 2.4 V
12
01100
13
01101
14
01110
General Purpose ADIN12
Touch screen Y+
General Purpose ADIN13
Touch screen Y-
General Purpose ADIN14
0-200 mV / 0-2.0 V
0 – 1.2
0-200 mV / 0-2.0 V
0 – 1.2
0-200 mV / 0-2.0 V
10x / 1x
x2
10x / 1x
x2
10x / 1x
0 – 2.4 V
0 – 2.4 V
0 – 2.4 V
0 – 2.4 V
0 – 2.4 V
15
01111
General Purpose ADIN15
0-200 mV / 0-2.0 V
10x / 1x
0 – 2.4 V
16
10000
General Purpose ADIN16
0-200 mV / 0-2.0 V
10x / 1x
0 – 2.4 V
17
10001
General Purpose ADIN17
0-200 mV / 0-2.0 V
10x / 1x
0 – 2.4 V
18
10010
General Purpose ADIN18
0-200 mV / 0-2.0 V
10x / 1x
0 – 2.4 V
19
10011
20
10100
General Purpose ADIN19
General Purpose ADIN20
0-200 mV / 0-2.0 V
0-200 mV / 0-2.0 V
10x / 1x
10x / 1x
0 – 2.4 V
0 – 2.4 V
21
10101
General Purpose ADIN21
0-200 mV / 0-2.0 V
10x / 1x
0 – 2.4 V
22
10110
Reserved
Reserved
Reserved
Reserved
23
10111
Reserved
Reserved
Reserved
Reserved
24
11000
25
11001
26
11010
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
27
11011
Reserved
Reserved
Reserved
Reserved
28
11100
Reserved
Reserved
Reserved
Reserved
29
11101
Reserved
Reserved
Reserved
Reserved
30
11110
31
11111
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Notes
18. Equivalent to -3.0 to +3.0 A of current with a 20 mOhm sense resistor
Some of the internal signals are first scaled to adapt the range to the input range of the ADC. Note that the 10 bit ADC core
will convert over the entire scaled version of the input channel, so always from a 2.40 V, full scale.
For some applications, an external resistor divider network may be used to scale down the voltage to be measured to the ADC
input range. The source resistance presented by this may be greater than the maximum specified Rs, see ADC Section on
Table 3. In that case, the readout value will be lower than expected due to the dynamic input impedance of the ADC converter.
This readout error presents itself as a gain error which can be compensated for by factory phasing. An alternative is to place a
100 nF bypass capacitor at the ADIN input concerned.
RESERVED CHANNELS POSSIBLE USAGE
Only 22 of the possible 32 ADC channels are currently associated with an specific function. The remaining channels are
currently designated as reserved channels for future needs. Table 58 is a proposed usage for some of these channels for
additional flexibility.
900844
90
Analog Integrated Circuit Device Data
Freescale Semiconductor