Information

ADCx_SC1n field descriptions (continued)
Field Description
0 Single-ended conversions and input channels are selected.
1 Differential conversions and input channels are selected.
4–0
ADCH
Input channel select
The ADCH bits form a 5-bit field that selects one of the input channels. The input channel decode
depends on the value of the DIFF bit. DAD0-DAD3 are associated with the input pin pairs DADPx and
DADMx.
The successive approximation converter subsystem is turned off when the channel select bits are all set
(ADCH = 11111). This feature allows for explicit disabling of the ADC and isolation of the input channel
from all sources. Terminating continuous conversions this way prevents an additional single conversion
from being performed. It is not necessary to set the channel select bits to all ones to place the ADC in a
low-power state when continuous conversions are not enabled because the module automatically enters
a low-power state when a conversion completes.
00000 When DIFF=0, DADP0 is selected as input; when DIFF=1, DAD0 is selected as input.
00001 When DIFF=0, DADP1 is selected as input; when DIFF=1, DAD1 is selected as input.
00010 When DIFF=0, DADP2 is selected as input; when DIFF=1, DAD2 is selected as input.
00011 When DIFF=0, DADP3 is selected as input; when DIFF=1, DAD3 is selected as input.
00100 When DIFF=0, AD4 is selected as input; when DIFF=1, it is reserved.
00101 When DIFF=0, AD5 is selected as input; when DIFF=1, it is reserved.
00110 When DIFF=0, AD6 is selected as input; when DIFF=1, it is reserved.
00111 When DIFF=0, AD7 is selected as input; when DIFF=1, it is reserved.
01000 When DIFF=0, AD8 is selected as input; when DIFF=1, it is reserved.
01001 When DIFF=0, AD9 is selected as input; when DIFF=1, it is reserved.
01010 When DIFF=0, AD10 is selected as input; when DIFF=1, it is reserved.
01011 When DIFF=0, AD11 is selected as input; when DIFF=1, it is reserved.
01100 When DIFF=0, AD12 is selected as input; when DIFF=1, it is reserved.
01101 When DIFF=0, AD13 is selected as input; when DIFF=1, it is reserved.
01110 When DIFF=0, AD14 is selected as input; when DIFF=1, it is reserved.
01111 When DIFF=0, AD15 is selected as input; when DIFF=1, it is reserved.
10000 When DIFF=0, AD16 is selected as input; when DIFF=1, it is reserved.
10001 When DIFF=0, AD17 is selected as input; when DIFF=1, it is reserved.
10010 When DIFF=0, AD18 is selected as input; when DIFF=1, it is reserved.
10011 When DIFF=0, AD19 is selected as input; when DIFF=1, it is reserved.
10100 When DIFF=0, AD20 is selected as input; when DIFF=1, it is reserved.
10101 When DIFF=0, AD21 is selected as input; when DIFF=1, it is reserved.
10110 When DIFF=0, AD22 is selected as input; when DIFF=1, it is reserved.
10111 When DIFF=0, AD23 is selected as input; when DIFF=1, it is reserved.
11000 Reserved.
11001 Reserved.
11010 When DIFF=0, Temp sensor (single-ended) is selected as input; when DIFF=1, Temp sensor
(differential) is selected as input.
11011 When DIFF=0,Bandgap (single-ended) is selected as input; when DIFF=1, Bandgap (differential)
is selected as input.
11100 Reserved.
11101 When DIFF=0, V
REFSH
is selected as input; when DIFF=1, -V
REFSH
(differential) is selected as
input. Voltage reference selected is determined by the REFSEL bits in the SC2 register.
11110 When DIFF=0, V
REFSL
is selected as input; when DIFF=1, it is reserved. Voltage reference
selected is determined by the REFSEL bits in the SC2 register.
11111 Module disabled.
Chapter 31 Analog-to-Digital Converter (ADC)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 587