WM9713LGEFL/RV Wolfson Microelectronics, WM9713LGEFL/RV Datasheet - Page 73

• Manufacturer Part Number: WM9713LGEFL/RV
• Description: Audio CODECs Stereo AC'97 CODEC T/P Interface
• Manufacturer: Wolfson Microelectronics

Specifications of WM9713LGEFL/RV

• Number Of Adc Inputs: 1
• Number Of Dac Outputs: 1
• Conversion Rate: 8 KSPs
• Interface Type: AC97
• Resolution: 12 bit
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-48
• Minimum Operating Temperature: - 25 C
• Number Of Channels: 1 ADC, 1 DAC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Pre-Production
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CONVERSION RATE
As stated previously the conversion rate is specified by the CR bits (reg 76h).
CR may be set to 93.75Hz (every 512 AC-Link Frames), 120Hz (every 400 AC-Link Frames),
153.75Hz (every 312 AC-Link frames) or 187.5Hz (every 256 AC-Link frames).
If only one ADRSEL[7:1] bit is set then each individual conversion occurs at the rate specified by
CR.
If multiple ADRSEL[7:1] bits are set then the complete set of conversions requested is completed at
the rate specified by CR.
DATA READBACK
This data is stored in register 7Ah, and can be retrieved by reading the register in the usual manner
(see AC-Link Interface section). Additionally, the data can also be passed to the controller on one of
the AC-Link time slots not used for audio functions.
The output data word of the touchpanel interface consists of three parts:
If the data is being read back using the polling method, there are several ways to determine when a
measurement has finished:
Table 50 Touchpanel Digitiser Data
7Ah
or
AC-Link slot
selected by
SLT
78h
REGISTER
ADDRESS
•
•
•
•
•
•
Reading back the POLL bit. If it has been reset to ‘0’, then the measurement has finished.
Monitoring the ADA signal, see GPIO and interrupt section. ADA goes high after every
single conversion. If operating in co-ordinate mode (COO=1) then ADA goes high after
every group of 3 conversions.
Reading back 7Ah until the new data appears
Pen Status (1 bit) – this is also passed to the GPIO logic block, which can be
programmed to generate an interrupt and/or wake up the WM9713L on pen down
(see GPIO and Interrupt Control).
Output data from the touchpanel ADC (12 bits)
ADCSRC: 3 additional bits that indicate the source of the ADC data. In co-ordinate
mode (COO = ‘1’), the WM9713L schedules different types of measurements
autonomously and so these register bits may be required.
15
14:12
11:0
9
BIT
PNDN
ADCSRC
ADCD
WAIT
LABEL
0
000
000h
0
DEFAULT
Pen Status (Read-only)
0 = Pen up
1 = Pen down
Touchpanel ADC Source
000 = No measurement
001 = X co-ordinate measurement
010 = Y co-ordinate measurement
011 = Pressure measurement (4-wire only)
100 = COMP1/AUX1 measurement (pin 29)
101 = COMP2/AUX2 measurement (pin 30)
110 = AUX3 measurements (SPKVDD/3)
111 = WIPER/AUX4 measurement (pin 12)
Touchpanel ADC Data (Read-only)
Bit 0 = LSB
Bit 11 = MSB
Touchpanel ADC Data Control
0 = Overwrite existing data in 7Ah with new
data
1 = Retain existing data in 7Ah until it is read
DESCRIPTION
PP Rev 3.2 September 2008
WM9713L
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