ad7879-1acbz-rl Analog Devices, Inc., ad7879-1acbz-rl Datasheet - Page 15

• Manufacturer Part Number: ad7879-1acbz-rl
• Description: Low Voltage Controller For Touch Screens
• Manufacturer: Analog Devices, Inc.

Temperature Calculations
If an explicit temperature reading in degrees Celsius is required,
calculate for the single measurement method by
1.
2.
3.
4.
5.
Calculate the scale factor of the ADC in degrees per LSB
Degrees per LSB = ADC LSB size/−2.1 mV =
(V
Save the ADC output (D
temperature, T
Take the ADC reading, D
measured, T
Calculate the difference in degrees between T
ΔT = (D
Add ΔT to T
CC
/4096)/−2.1 mV
AMB
− D
AMB
CAL
CAL
.
.
CAL
.
) × degrees per LSB
CAL
AMB
) at the calibration
, at the temperature to be
CAL
and T
AMB
by
Rev. 0 | Page 15 of 36
Example
Using V
The ADC output is 983 decimal at 25°C, equivalent to a diode
forward voltage of 0.6 V.
The ADC output at T
Degrees per LSB = (2.5/4096)/−2.1 × 10
ΔT = (880 − 983) × −0.291 = 30°C
T
AMB
CC
= 25 + 30 = 55°C
= 2.5 V as reference,
AMB
is 880.
−3
= −0.291
AD7879