Datasheet

Chapter 10 Analog-to-Digital Converter (S08ADC12V1)
MC9S08JM60 Series Data Sheet, Rev. 3
136 Freescale Semiconductor
NOTE
Selecting the internal bandgap channel requires BGBE =1 in SPMSC1 see
Section 5.7.7, “System Power Management Status and Control 1 Register
(SPMSC1).” For value of bandgap voltage reference see Appendix A.8,
“Analog Comparator (ACMP) Electricals.”
10.1.1.2 Alternate Clock
The ADC is capable of performing conversions using the MCU bus clock, the bus clock divided by two,
the local asynchronous clock (ADACK) within the module, or the alternate clock (ALTCLK). The
ALTCLK on this device is the MCGERCLK.
The selected clock source must run at a frequency such that the ADC conversion clock (ADCK) runs at a
frequency within its specified range (f
ADCK
) after being divided down from the ALTCLK input as
determined by the ADIV bits.
ALTCLK is active while the MCU is in wait mode provided the conditions described above are met. This
allows ALTCLK to be used as the conversion clock source for the ADC while the MCU is in wait mode.
ALTCLK cannot be used as the ADC conversion clock source while the MCU is in stop3.
10.1.1.3 Hardware Trigger
The RTC on this device can be enabled as a hardware trigger for the ADC module by setting the
Table 10-1. ADC Channel Assignment
ADCH Channel Input Pin Control ADCH Channel Input Pin Control
00000 AD0 PTB0/MISO2/ADP0 ADPC0 10000 AD16 V
REFL
N/A
00001 AD1 PTB1/MOSI2/ADP1 ADPC1 10001 AD17 V
REFL
N/A
00010 AD2 PTB2/SPSCK2/ADP2 ADPC2 10010 AD18 V
REFL
N/A
00011 AD3 PTB3/SS2
/ADP3 ADPC3 10011 AD19 V
REFL
N/A
00100 AD4 PTB4/KBIP4/ADP4 ADPC4 10100 AD20 V
REFL
N/A
00101 AD5 PTB5/KBIP5/ADP5 ADPC5 10101 AD21 Reserved N/A
00110 AD6 PTB6/ADP6 ADPC6 10110 AD22 Reserved N/A
00111 AD7 PTB7/ADP7 ADPC7 10111 AD23 Reserved N/A
01000 AD8 PTD0/ADP8/ACMP+ ADPC8 11000 AD24 Reserved N/A
01001 AD9 PTD1/ADP9/ACMP- ADPC9 11001 AD25 Reserved N/A
01010 AD10 PTD3/KBIP3/ADP10 ADPC10 11010 AD26 Temperature
Sensor
1
1
For more information, see Section 10.1.1.5, “Temperature Sensor.”
N/A
01011 AD11 PTD4/ADP11 ADPC11 11011 AD27 Internal Bandgap N/A
01100 AD12 V
REFL
ADPC12 11100 Reserved N/A
01101 AD13 V
REFL
ADPC13 11101 V
REFH
V
REFH
N/A
01110 AD14 V
REFL
ADPC14 11110 V
REFL
V
REFL
N/A
01111 AD15 V
REFL
ADPC15 11111 module
disabled
None N/A