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)
TSC
NotAddressed
NoTouch
Detected
HostWriteto
ControlByte1D[6:3]
As DAV
WaitingforHostto
ReadAUXData
TSC
NotAddressed
Reading
AUX-Data
Register
Sample,Conversion,and
AveragingforAUXMeasurement
TSC
NotAddressed
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)
TSC
NotAddressed
NoTouch
Detected
HosttoWriteto
ControlByte1D[6:3]
As DAV
TSC
NotAddressed
Reading
AUX-Data
Register
Sample,Conversion,
andAveragingfor
AUXMeasurement
TSC
NotAddressed
P ograr mm dfor
Continuous
AUXMeasurement
e
TSC
Not
Addressed
Reading
AUX-Data
Register
t
COORDINATE
t
COORDINATE
t
COORDINATE
Sample,Conversion,
andAveragingfor
AUXMeasurement
Sample,Conversion,
andAveragingfor
AUXMeasurement
TSC2004
SBAS408E – JUNE 2007 – REVISED MARCH 2008
The TSC2004 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 46 (converter function select bits C[3:0] = Control Byte 1
D[6:3] = 0101); or
2. Continuous AUX Measurement shown in Figure 47 (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 Internal Temperature Sensor
section. These two converter functions have the same timing as the non-continuous AUX measurement
operation as shown in Figure 46 ; 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 46. Non-Touch Screen, Non-Continuous AUX Measurement
The time needed to make continuous auxiliary measurement is given by:
Figure 47. Non-Touch Screen, Continuous AUX Measurement
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Product Folder Link(s): TSC2004