sx8675iwltrt Semtech Corporation, sx8675iwltrt Datasheet - Page 19

• Manufacturer Part Number: sx8675iwltrt
• Description: Haptics Enabled Multitouch 4/5-wire Resistive Touchscreen Controller With Proximity Sensing
• Manufacturer: Semtech Corporation

ADVANCED COMMUNICATIONS & SENSING
The parameter SETDLY sets the settling time between the consecutive conversions of the same channel.
In most applications, SETDLY can be set to minimum (0.5us). However, in some particular applications where
an accuracy of 1LSB is required SETDLY may need to be increased.
4.7
4.7.1
The chip has three operating modes that are configured using the I2C as defined in § 11 :
At power-up the chip is set in manual mode.
4.7.2
In manual mode (MAN) the touchscreen interface is stopped and conversions must be manually triggered by the
host using SELECT and CONVERT command.
Rev 1 – 25
Host Operation
Overview
Manual (command ‘MAN’ and TOUCHRATE = 0).
Pen detect (command ‘PENDET’ and TOUCHRATE > 0).
Pen trigger (command ‘PENTRG’ and TOUCHRATE > 0).
Manual Mode (MAN)
th
July 2011
FILT
0
1
2
3
Nfilt Function
1
3
5
7
c
No average.
c
3 ADC samples are averaged.
c
5 ADC samples are averaged.
s
c
7 ADC samples are sorted and the 3 center samples are averaged.
n
n
max 1
n
n
=
=
=
=
Figure 19 – POWDLY and SETDLY (FILT=2)
1
-- -
3
s
1
-- -
3
1
-- -
5
n
Table 6 – Digital Processing Functions
4079
-- -- -- -- -- - - s
4095
4079
- - -- -- -- -- - - s
4095
4079
- - -- -- -- -- - - s
4095
s
m ax2
a
n
n
+
+
+
s
b
s
s
n 1
n 1
s
+
a
Resistive Touchscreen Controller with Proximity Sensing
–
–
s
c
s
+
+
19
b
s
s
n 2
n 2
–
s
–
c
+
s
s
min 1
n 3
SX8674/SX8675/SX8676
–
+
s
Haptics Enabled Multitouch 4/5-Wire
n 4
s
m in 2
–
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