sc9s08mz16 Freescale Semiconductor, Inc, sc9s08mz16 Datasheet - Page 198

• Manufacturer Part Number: sc9s08mz16
• Description: Hcs08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 11 Analog-to-Digital Converter (S08ADC10V1)
f
frequency requirement, when an oscillator circuit is used it must be configured for high range operation
(RANGE = 1).
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.
11.2.2
The ADC hardware trigger, ADHWT, is output from the real time interrupt (RTI) counter. The RTI counter
can be clocked by either ICGERCLK or a nominal 1 kHz clock source within the RTI block. The 1 kHz
clock source can be used with the MCU in run, wait, or stop3. With the ICG configured for either FBE or
FEE mode, ICGERCLK can be used with the MCU in run or wait.
The period of the RTI is determined by the input clock frequency and the RTIS bits. When the ADC
hardware trigger is enabled, a conversion is initiated upon an RTI counter overflow. The RTI counter is a
free running counter that generates an overflow at the RTI rate determined by the RTIS bits.
11.2.2.1
The ADC on SC9S08MZ16 contains only two analog pin enable registers, APCTL1 and APCTL2.
11.2.2.2
The ADC is capable of running in stop3 mode but requires LVDSE and LVDE in SPMSC1 to be set.
11.2.3
The ADC1 module includes a temperature sensor whose output is connected to one of the ADC analog
channel inputs.
where:
For temperature calculations, use the V
In application code, the user reads the temperature sensor channel, calculates V
V
less than V
For more information on using the temperature sensor, consult AN3031.
198
ADCK
TEMP25
and the maximum frequency is four times the maximum value for f
— V
— V
— m is the hot or cold voltage versus temperature slope in V/°C.
. If V
TEMP25
Hardware Trigger
Temperature Sensor
TEMP
TEMP25
Analog Pin Enables
Low-Power Mode Operation
TEMP
Equation 11-1
is the voltage of the temperature sensor channel at the ambient temperature.
the hot slope value is applied in
is greater than V
is the voltage of the temperature sensor channel at 25°C.
provides an approximate transfer function of the temperature sensor.
Temp = 25 - ((V
SC9S08MZ16 MCU Data Sheet, Rev. 1
TEMP25
TEMP25
the cold slope value is applied in
TEMP
and m values from the ADC Electricals table.
-V
Equation
TEMP25
) ÷ m)
11-1.
ADCK
Equation
. Because of the minimum
TEMP
Freescale Semiconductor
, and compares to
11-1. If V
Eqn. 11-1
TEMP
is