mc9s08jm60 Freescale Semiconductor, Inc, mc9s08jm60 Datasheet - Page 137

• Manufacturer Part Number: mc9s08jm60
• Description: Hcs08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

ADCSC2[ADTRG] bit. When enabled, the ADC will be triggered every time RTCINT matches
RTCMOD. The RTC interrupt does not have to be enabled to trigger the ADC.
The RTC can be configured to cause a hardware trigger in MCU run, wait, and stop3.
10.1.1.4
The ADC on MC9S08JM60 series contains only two analog pin enable registers, APCTL1 and APCTL2.
10.1.1.5
The ADC 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
is less than V
To improve accuracy, calibrate the bandgap voltage reference and temperature sensor. Calibrating at
25 °C will improve accuracy to ±4.5°C. Calibration at 3 points, –40°C, 25°C, and 125°C will improve
accuracy to ±2.5°C. Once calibration has been completed, the user will need to calculate the slope for both
hot and cold. In application code, the user would then calculate the temperature using
detailed above and then determine if the temperature is above or below 25°C. Once determined, if the
temperature is above or below 25°C, the user can recalculate the temperature using the hot or cold slope
value obtained during calibration.
10.1.2
The ADC is capable of running in stop3 mode but requires LVDSE and LVDE in SPMSC1 to be set.
Freescale Semiconductor
TEMP25
— V
— V
— m is the hot or cold voltage versus temperature slope in V/°C.
. If V
Low-Power Mode Operation
TEMP
TEMP25
TEMP25
Analog Pin Enables
Temperature Sensor
TEMP
Equation 10-1
is the voltage of the temperature sensor channel at the ambient temperature.
is greater than V
is the voltage of the temperature sensor channel at 25°C.
the hot slope value is applied in
Temp = 25 – ((V
provides an approximate transfer function of the temperature sensor.
MC9S08JM60 Series Data Sheet, Rev. 2
TEMP25
TEMP25
, the cold slope value is applied in
TEMP
and m values from the ADC Electricals table.
– V
TEMP25
Equation
) ÷ m)
Chapter 10 Analog-to-Digital Converter (S08ADC12V1)
10-1.
Equation
TEMP
, and compares to
Equation 10-1
10-1. If V
Eqn. 10-1
TEMP
as
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