wm9715l Wolfson Microelectronics plc, wm9715l Datasheet - Page 46

• Manufacturer Part Number: wm9715l
• Description: Ac?97 Audio And Touchpanel Codec
• Manufacturer: Wolfson Microelectronics plc

WM9715L
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Setting DEL to ‘1111’ reduces the settling time to zero, i.e. measurements begin immediately. This
mode is intended for fast sampling on AUX inputs. It is NOT intended for touchpanel digitisation.
There are several side-effects when DEL is set to ‘1111’:
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Co-ordinate mode does not work, i.e. the WM9715L behaves as if COO = 0, even if COO
= 1 (see “Measurement Types”)
If X / Y co-ordinate or touch pressure measurements are selected (ADCSEL = 001, 010
or 011), then the switch matrix is constantly on, and current constantly flows in the
touchpanel. This increases power consumption in the system, and is therefore not
recommended for battery powered systems
In continuous mode (CTC = 1), setting DEL = 1111 increases the sampling rate of the
touchpanel ADC (see “Initiation of Measurements”)
PD Rev 4.0 December 2007
Production Data
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