Datasheet

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AUXILIARY AND TEMPERATURE MEASUREMENT
t
COORDINATE
+
OH3
f
OSC
)N @
ǒ(
B)2
)
@
f
OSC
f
ADC
)OH
CONV
Ǔ
@
ǒ
1
f
OSC
Ǔ
)
ǒ
L
PPRO
f
OSC
Ǔ
(12)
CS
Deactivated
NoTouch
Detected
HostWriteto
ControlByte1D[6:3]
As DAV
WaitingforHostto
ReadAUXData
CS
Deactivated
Reading
AUX-Data
Register
Sample,Conversion,and
AveragingforAUXMeasurement
CS
Deactivated
P ograr mm dfor
Non-Continuous
AUXMeasurement
e
t
COORDINATE
NoTouch
Detected
t
COORDINATE
+
OH3
f
OSC
)N @
ǒ(
B)2
)
@
f
OSC
f
ADC
)OH
CONV
Ǔ
@
ǒ
1
f
OSC
Ǔ
)
ǒ
L
PPRO
f
OSC
Ǔ
(13)
CS
Deactivated
NoTouch
Detected
HosttoWriteto
ControlByte1D[6:3]
As DAV
CS
Deactivated
Reading
AUX-Data
Register
Sample,Conversion,
andAveragingfor
AUXMeasurement
CS
Deactivated
P ograr mm dfor
Continuous
AUXMeasurement
e
CS
Deactivated
Reading
AUX-Data
Register
t
COORDINATE
t
COORDINATE
t
COORDINATE
Sample,Conversion,
andAveragingfor
AUXMeasurement
Sample,Conversion,
andAveragingfor
AUXMeasurement
TSC2005
SBAS379C – DECEMBER 2006 – REVISED MARCH 2008
The TSC2005 can measure the voltage from the auxiliary input (AUX) and from the internal temperature sensor.
Applications for the AUX can include external temperature sensing, ambient light monitoring for controlling
backlighting, or sensing the current drawn from batteries. There are two converter functions that can be used for
the measurement of the AUX:
1. Non-continuous AUX measurement shown in Figure 39 (converter function select bits C[3:0] = Control Byte 1
D[6:3] = 0101); or
2. Continuous AUX Measurement shown in Figure 40 (converter function select bits C[3:0] = Control Byte 1
D[6:3] = 1000).
See Table 7 for more information on the converter function select bits.
There are also two converter functions for the measurement of the internal temperature sensor:
1. TEMP1 measurement (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0110); or
2. TEMP2 measurement (converter function select bits C[3:0] = Control Byte 1 D[6:3] = 0111).
See Table 7 for more information on the converter function select bits.
For the detailed calculation of the internal temperature sensor, please see the SubSec1 9.3 section. These two
converter functions have the same timing as the non-continuous AUX measurement operation as shown in
Figure 39 ; therefore, Equation 12 can also be used for internal temperature sensor measurement. The time
needed to make a non-continuous auxiliary measurement or an internal temperature sensor measurement is
given by:
Where:
OH3 = overhead time #3 = 3.5 internal clock cycles.
Figure 39. Non-Touch Screen, Non-Continuous AUX Measurement
The time needed to make continuous auxiliary measurement is given by:
Figure 40. Non-Touch Screen, Continuous AUX Measurement
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