wm9715l Wolfson Microelectronics plc, wm9715l Datasheet
wm9715l
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wm9715l Summary of contents
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... AC’97 Audio and Touchpanel CODEC DESCRIPTION The WM9715L is a highly integrated input / output device designed for mobile computing and communications. The device can connect directly to a 4-wire or 5-wire touchpanel, mono or stereo microphones, stereo headphones and a mono speaker, reducing total component count in the system ...
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... WM9715L DESCRIPTION .......................................................................................................1 FEATURES.............................................................................................................1 APPLICATIONS .....................................................................................................1 BLOCK DIAGRAM .................................................................................................1 TABLE OF CONTENTS .........................................................................................2 PIN CONFIGURATION...........................................................................................4 ORDERING INFORMATION ..................................................................................4 PIN DESCRIPTION ................................................................................................5 ABSOLUTE MAXIMUM RATINGS.........................................................................6 RECOMMENDED OPERATING CONDITIONS .....................................................6 ELECTRICAL CHARACTERISTICS ......................................................................7 AUDIO OUTPUTS.......................................................................................................... 7 AUDIO INPUTS.............................................................................................................. 8 AUXILIARY MONO DAC (AUXDAC).............................................................................. 8 TOUCHPANEL AND AUXILIARY ADC .......................................................................... 9 COMPARATORS ........................................................................................................... 9 REFERENCE VOLTAGES ........................................................................................... 10 DIGITAL INTERFACE CHARACTERISTICS................................................................ 10 HEADPHONE / SPEAKER OUTPUT THD VERSUS POWER ..................................... 11 POWER CONSUMPTION ...
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... APPLICATIONS INFORMATION .........................................................................72 RECOMMENDED EXTERNAL COMPONENTS........................................................... 72 RECOMMENDED COMPONENTS VALUES ............................................................... 73 LINE OUTPUT ............................................................................................................. 73 AC-COUPLED HEADPHONE OUTPUT....................................................................... 74 DC COUPLED (CAPLESS) HEADPHONE OUTPUT ................................................... 74 BTL LOUDSPEAKER OUTPUT ................................................................................... 75 COMBINED STEREO HEADSET / BTL EAR SPEAKER ............................................. 75 COMBINED HEADSET / SINGLE-ENDED EAR SPEAKER......................................... 75 PACKAGE DIMENSIONS ....................................................................................76 IMPORTANT NOTICE ..........................................................................................77 ADDRESS:................................................................................................................... 77 w WM9715L PD Rev 4.0 December 2007 3 ...
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... WM9715L PIN CONFIGURATION ORDERING INFORMATION DEVICE TEMP. RANGE WM9715LGEFL/V -25 to +85 WM9715LGEFL/RV -25 to +85 Note: Reel quantity = 2,200 w PACKAGE 48-lead QFN o C (Pb-free) 48-lead QFN o C (Pb-free, tape and reel) Production Data MOISTURE LEVEL PEAK SOLDERING TEMP SENSITIVITY MSL3 o 260 C MSL3 o 260 C PD Rev 4.0 December 2007 ...
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... Digital Output Clock Crystal Connection 2 Supply Digital Ground (return path for both DCVDD and DBVDD) Digital Input Serial Data Output from Controller / Input to WM9715L Digital Output Serial Interface Clock Output to Controller Digital Ground (return path for both DCVDD and DBVDD) Supply ...
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... WM9715L ABSOLUTE MAXIMUM RATINGS Absolute Maximum Ratings are stress ratings only. Permanent damage to the device may be caused by continuously operating at or beyond these limits. Device functional operating limits and guaranteed performance specifications are given under Electrical Characteristics at the test conditions specified. ESD Sensitive Device. This device is manufactured on a CMOS process therefore generically susceptible to damage from excessive static voltages ...
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... =20mW, R =32Ω SNR o C, 1kHz signal 48kHz, 18-bit audio data unless MIN TYP MAX -86 -80 50 400 500 -65 0. -80 -81 -77 -70 - =16Ω, THD Rev 4.0 December 2007 WM9715L UNIT V rms ...
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... WM9715L AUDIO INPUTS Test Conditions DBVDD=3.3V, DCVDD = 3.3V, AVDD = 3.3V, T PARAMETER LINEINL/R, MICL/R and PHONE pins Full Scale Input Signal Level (for ADC 0dB Input at 0dB Gain) Input Resistance Input Capacitance Line input to ADC (LINEINL, LINEINR) Signal to Noise Ratio (A-weighted) Total Harmonic Distortion Power Supply Rejection Microphone input to 32Ω ...
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... AUX ADC input DNL INL PSRR R RPU = 000001 PU I PIL = 1 P PIL = 0 AVDD = 3.3V AVDD = 1.8V during measurement average over time SYMBOL TEST CONDITIONS pin not selected as AUX ADC input 24.576MHz crystal WM9715L MIN TYP MAX AGND AVDD <10 12 ±0.15 -0.99 +1.75 ±3 ±4 ± VDD/2 ...
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... WM9715L REFERENCE VOLTAGES Test Conditions DBVDD=3.3V, DCVDD = 3.3V, AVDD = 3.3V, T PARAMETER Audio ADCs, DACs, Mixers Reference Input/Output Buffered Reference Output Microphone Bias Bias Voltage Bias Current Source Output Noise Voltage DIGITAL INTERFACE CHARACTERISTICS Test Conditions DBVDD = 3.3V, DCVDD = 3.3V PARAMETER Digital Logic Levels (all digital input or output pins) – CMOS Levels ...
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... Production Data HEADPHONE / SPEAKER OUTPUT THD VERSUS POWER -20 Headphone Power vs THD+N (32Ohm load) -40 -60 -80 -100 Power (mW) -20 Headphone Power vs THD+N (16Ohm load) -40 -60 -80 -100 Power (mW WM9715L PD Rev 4.0 December 2007 11 ...
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... Supply voltages: Reducing the supply voltages also reduces digital supply currents, and therefore results in significant power savings especially in the digital sections of the WM9715L. • Operating mode: Significant power savings can be achieved by always disabling parts of the WM9715L that are not used (e.g. audio ADC, DAC, touchpanel digitiser). Mode Description ...
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... Production Data DEVICE DESCRIPTION INTRODUCTION The WM9715L is designed to meet the mixed-signal requirements of portable and wireless computer systems. It includes audio recording and playback, touchpanel digitisation, battery monitoring, auxiliary ADC and interrupt functions, all controlled through a single 5-wire AC-Link interface. SOFTWARE SUPPORT The basic audio features of the WM9715L are software compatible with standard AC’97 device drivers ...
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... WM9715L AUDIO PATHS OVERVIEW 20h:7 (Loopback) L Slot 3 ADC Left 1 Left Channel Tone and 3D 08h / 22h / 18 Bit DAC AC Link 0 20h:13 (3DE) 10h:12-8 00000 = +12dB 11111 = -34.5dB LINEINL to SPKR MIXER LINEL PGA Pin 23 PCBEEP Pin 19 0Ch:0-4 00000 = +12dB 11111 = -34.5dB PHONE PHONE PGA ...
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... LINEINR input gain VOL (0dB) similar to LINEINLVOL 15 L2H 1 Mute LINEIN path to headphone mixer 1: Mute mute (ON) 14 L2S 1 Mute LINEIN path to speaker mixer 1: Mute mute (ON) 13 L2P 1 Mute LINEIN path to phone mixer 1: Mute mute (ON) WM9715L DESCRIPTION PD Rev 4.0 December 2007 15 ...
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... WM9715L It is also possible to use the LINEINL and LINEINR pins as a second differential microphone input. This is achieved by setting the DS bit (register 5Ch, bit 11) to ‘1’. This disables the line-in audio paths and routes the signal from LINEINL and LINEINR through the differential mic path came from the MIC1 and MIC2 pins ...
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... BIT LABEL DEFAULT 15 P2H 1 Mute PHONE path to headphone mixer 1: Mute mute (ON) 14 P2S 1 Mute PHONE path to speaker mixer 1: Mute mute (ON) 4:0 PHONE 01000 PHONE input gain VOL (0dB) 00000: +12dB … (1.5dB steps) 11111: -34.5dB WM9715L DESCRIPTION PD Rev 4.0 December 2007 17 ...
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... WM9715L PCBEEP INPUT Pin 19 (PCBEEP mono, line level input intended for externally generated signal or warning tones routed directly to the record selector and all three output mixers, without an input amplifier. The signal gain into each mixer can be independently controlled, with a separate mute bit for each signal path ...
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... ADC data appears on both the left and right AC-Link slots. HIGH PASS FILTER The WM9715L audio ADC incorporates a digital high-pass filter that eliminates any DC bias from the ADC output data. The filter is enabled by default. For DC measurements, it can be disabled by writing a ‘ ...
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... WM9715L RECORD SELECTOR The record selector determines which input signals are routed into the audio ADC. The left and right channels can be selected independently. This is useful for recording a phone call: one channel can be used for the RX signal and the other for the TX signal, so that both sides of the conversation are digitized ...
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... Record Gain changes immediately 1: Record Gain changes when signal is zero or after time-out 6 GRR 0 Gain range select (right) Similar to GRL 5:0 RECVOLR 000000 Record Volume (right) Similar to RECVOLL WM9715L DESCRIPTION Extended (GRL=1) 000000: -17.25dB 000001: -16.5dB … (0.75dB steps) 111111: +30dB PD Rev 4.0 December 2007 21 ...
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... WM9715L AUTOMATIC LEVEL CONTROL The WM9715L has an automatic level control that aims to keep a constant recording volume irrespective of the input signal level. This is achieved by continuously adjusting the PGA gain so that the signal level at the ADC input remains constant. A digital peak detector monitors the ADC output and changes the PGA gain if necessary ...
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... ATK 0010 ALC attack (gain ramp-down) time (24ms) 0000 = 6ms 0001 = 12ms 0010 = 24ms … (time doubles with every step) 1010 or higher = 6.14s WM9715L DESCRIPTION 17 x MCLK period 16 x MCLK period 15 x MCLK period 14 x MCLK period PD Rev 4.0 December 2007 ...
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... When the signal is very quiet and consists mainly of noise, the ALC function may cause “noise pumping”, i.e. loud hissing noise during silence periods. The WM9715L has a noise gate function that prevents noise pumping by comparing the signal level at the input pins (i.e. before the record PGA) against a noise gate threshold, NGTH ...
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... DAC. (Contrary to the AC’97 specification, they have no effect on analogue input signals or signals played through the auxiliary DAC. Nevertheless, the ID2 and ID5 bits in the reset register, 00h, are set to ‘1’ to indicate that the WM9715L supports tone control and bass boost.) The DAC output has a PGA for volume control. The DAC sample rate can be controlled by writing to a control register (see “ ...
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... WM9715L TONE CONTROL / BASS BOOST The WM9715L provides separate controls for bass and treble with programmable gains and filter characteristics. This function operates on digital audio data before it is passed to the audio DACs. Bass control can take two different forms: • Linear bass control: bass signals are amplified or attenuated by a user programmable gain ...
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... DEFAULT 13 3DE 0 (disabled) 5 3DLC 0 4 3DUC 0 3:0 3DDEPTH 0000 WM9715L DESCRIPTION 3D enhancement enable Lower Cut-off Frequency 0 = Low (200Hz at 48kHz sampling High (500Hz at 48kHz sampling) Upper Cut-off Frequency 0 = High (2.2kHz at 48kHz sampling Low (1.5kHz at 48kHz sampling) 3D Depth 0000: 0% (minimum 3D effect) 0001: 6.67% … 1110: 93.3% 1111: 100% (maximum) PD Rev 4 ...
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... WM9715L AUXILIARY DAC AUXDAC is a simple 12-bit mono DAC. It can be used to generate DC signals (with the numeric input written into a control register signals such as telephone-quality ring tones or system beeps (with the input signal supplied through an AC-Link slot mode (XSLE = 1), the input data is binary offset coded ...
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... Under these circumstances, the AUXDAC cannot convert high digital input values to the correct analogue equivalent; its digital input range must therefore be limited accordingly. If necessary, this limitation can be circumvented by setting gains for the AUXDAC signal in register 12h using a higher DCVDD voltage. w (DCVDD-0.7) / √2 Vrms or AVDD / 3.3 Vrms WM9715L PD Rev 4.0 December 2007 29 ...
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... WM9715L ANALOGUE AUDIO OUTPUTS The following sections give an overview of the analogue audio output pins. For more information on recommended external components, please refer to the “Applications Information” section. HEADPHONE OUTPUTS – HPOUTL AND HPOUTR The HPOUTL and HPOUTR (pins 39 and 41) are designed to drive a 16Ω or 32Ω headphone or a line output ...
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... OUT3 Volume VOL (0dB) 000000: 0dB (maximum) 000001: -1.5dB … (1.5dB steps) 011111: -46.5dB 1xxxxx: -46.5dB WM9715L DESCRIPTION inverse of HPOUTR (for BTL ear speaker) VREF (for capless headphone drive) mono mix of both headphone channels (for single-ended ear speaker) inverse of MONOOUT (for differential mono output) PD Rev 4 ...
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... WM9715L LOUDSPEAKER OUTPUTS – LOUT2 AND ROUT2 The LOUT2 and ROUT2 outputs are designed to differentially drive an 8Ω mono speaker. They can also be used as a stereo line-out or headphone output. For speaker drive, the LOUT2 signal must be inverted (INV = 1), so that the left and right channel are added up in the speaker [R– ...
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... If the chip temperature reaches approximately 150°C, and the ENT bit is set, the WM9715L de-asserts bit 11 in register 54h, which can be set up to generate an interrupt to the CPU (see “Interrupt Control” section). ...
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... WM9715L DIGITAL AUDIO (SPDIF) OUTPUT The WM9715L supports the SPDIF standard using the SPDIF_OUT pin as its output. Register 3Ah is a read/write register that controls SPDIF functionality and manages bit fields propagated as channel status (or sub-frame in the V case). With the exception of V, this register should only be written to when the SPDIF transmitter is disabled (SPDIF bit in register 2Ah is ‘ ...
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... AUDIO MIXERS MIXER OVERVIEW The WM9715L has three separate low-power audio mixers to cover all audio functions required by smartphones, PDAs and handheld computers. The diagram below shows the routing of the analogue audio signals into the mixers. The numbers at the mixer inputs refer to the control register bits that control the volume and muting for that particular signal ...
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... WM9715L SPEAKER MIXER The speaker mixer drives the LOUT2 and ROUT2 output. The following signals can be mixed into the speaker path: • PHONE (controlled by register 0Ch, see “Audio Inputs”) • LINE_IN (controlled by register 10h, see “Audio Inputs”) • the stereo DAC signal (controlled by register 18h, see “Audio DACs”) • ...
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... Production Data VARIABLE RATE AUDIO / SAMPLE RATE CONVERSION By using an AC’97 Rev2.2 compliant audio interface, the WM9715L can record and playback at all commonly used audio sample rates, and offer full split-rate support (i.e. the DAC, ADC and AUXDAC sample rates are completely independent of each other – any combination is possible). ...
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... WM9715L TOUCHPANEL INTERFACE The WM9715L includes a touchpanel driver and digitiser circuit for use with 4-wire or 5-wire resistive touchpanels. The following functions are implemented: • X co-ordinate measurement • Y co-ordinate measurement • Pen down detection, with programmable sensitivity • Touch pressure measurement (4-wire touchpanel only) • ...
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... Pen down detection uses a zero power comparator (effectively a CMOS logic gate) with an internal, programmable pull-up resistor R touchpanel less sensitive to touch, while lowering that controls pen-down sensitivity. Increasing R PU makes it more sensitive. PU WM9715L makes the PU PD Rev 4.0 December 2007 39 ...
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... The PENDOWN signal can be transmitted through the PENDOWN pin (see “Interrupt Control” section). Additionally, its state is reflected in the PNDN bit (register 7Ah, bit 15) and the interrupt logic block (register 54h, bit 13), where it can wake the WM9715L from sleep mode (see “Interrupt Control” section). ...
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... Pen down detection works in a similar fashion for both 4-wire and 5-wire touchpanels (see Four-Wire Touchpanel Operation 5-wire touchpanel, all four contacts of the bottom plate are grounded, and the top plate contact is connected to the internal programmable pull-up resistor WM9715L . PU PD Rev 4.0 December 2007 ...
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... RPR 0 Wake-up on pen-down mode 0: Wake-up the AC-Link only (hold SDATAIN high until controller sends warm reset or cold reset) 1: Wake-up the WM9715L without waiting for a reset signal from the controller Production Data DESCRIPTION /1 = TYP 68kΩ (most sensitive TYP 34kΩ ...
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... Table 25 Touchpanel Digitiser Control (Initiation of Measurements) In continuous mode (CTC = 1), the WM9715L autonomously initiates measurements at the rate set by CR, and supplies the measured data to the CPU on one of the unused AC’97 time slots. DMA- enabled CPUs can write the data directly into a FIFO without any intervention by the CPU core. This reduces CPU loading and speeds up the execution of user programs in handheld systems ...
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... SLT 78h Table 27 Touchpanel Digitiser Data To avoid losing data that has not yet been read, the WM9715L can delay overwriting register 7Ah with new data until the old data has been read. This function is enabled using the WAIT bit. w BIT ...
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... TOUCHPANEL SETTLING TIME For accurate touchpanel measurements, some settling time may be required between the switch matrix applying a voltage across the touchpanel plate and the ADC sampling the signal. This time delay function is built into the WM9715L and can be programmed as shown below. REGISTER ADDRESS ...
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... AUX inputs NOT intended for touchpanel digitisation. There are several side-effects when DEL is set to ‘1111’: • Co-ordinate mode does not work, i.e. the WM9715L behaves as if COO = 0, even if COO = 1 (see “Measurement Types”) • 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 ...
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... Production Data AUXILIARY ADC INPUTS The ADC used for touchpanel digitisation can also be used for auxiliary measurements, provided that it is enabled (register 78h, PRP = 11). The WM9715L has four pins that can be used as auxiliary ADC inputs: • COMP1 / AUX1 (pin 29) • COMP2 / AUX2 (pin 30) • ...
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... WM9715L BATTERY ALARM AND ANALOGUE COMPARATORS The battery alarm function differs from battery measurement in that it does not actually measure the battery voltage. Battery alarm only indicates “OK”, “Low” or “Dead”. The advantage of the battery alarm function is that it does not require a clock and can therefore be used in low-power sleep or standby modes ...
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... Production Data The WM9715L has two on-chip comparators that can be used to implement a battery alarm function, or other functions such as a window comparator. Each comparator has one of its inputs tied to any one of three device pins and the other tied to a voltage reference. The voltage reference can be either internally generated (VREF = AVDD/2) or externally connected on AUX4 (pin 12) ...
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... COMP2 had never triggered. Note: If COMP2 triggers while the WM9715L is in sleep mode, and the delay is enabled, then the device starts the on-chip crystal oscillator in order to count the time delay. ...
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... THE ADCIRQ PIN In a typical use case with touchscreen measurements running continuously, “AUXADC data available” is the most frequent type of interrupt event from the WM9715L. In the interest of minimizing software overheads recommended to use the dedicated ADCIRQ pin to transmit this type of interrupt. ...
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... The GENIRQ output is enabled using registers 56h and 4Ch. Its polarity can be controlled using the IRQINV bit in register 58h, and interrupt wake-up (i.e. re-activating the AC-Link when an interrupt occurs after the WM9715L has been put into sleep mode, see “Power Management”) is enabled by the WAKEEN bit in register 58h. ...
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... Not Sticky (GIn bit follows internal interrupt signal) Interrupt Enable Wake Up (generate interrupts from this pin wake-up (no interrupts generated) xI N/A Interrupt Status Read: Returns status of each interrupt bit Write: Writing ‘0’ clears sticky bit WM9715L DESCRIPTION PD Rev 4.0 December 2007 53 ...
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... As can be seen from the table above, most blocks are ‘ON’ by default. However, if the PWRUP pin is held high during reset, the WM9715L starts up with all blocks powered down, saving power. This is achieved by connecting a pull-up resistor (e.g. 100kΩ) from PWRUP to DBVDD. Note that the state of PWRUP during reset only affects register 26h ...
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... The touchpanel digitiser is OFF by default. SLEEP MODE Whenever the PR4 bit (reg. 26h) is set, the AC-Link interface is disabled, and the WM9715L is in sleep mode. There is in fact a very large number of different sleep modes, depending on the other control bits. For example, the low-power standby mode described below is a sleep mode desirable to use sleep modes whenever possible, as this will save power ...
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... WM9715L LOW POWER STANDBY MODE If all the bits in registers 26h and 24h are set, then the WM9715L is in low-power standby mode and consumes very little current. A 1MΩ resistor string remains connected across AVDD to generate VREF. This is necessary if the on-chip analogue comparators are used (see “Battery Alarm and Battery Measurement” ...
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... RECSR = 001 in register 1Ah) in sleep or standby modes. However, should it be necessary to maintain the VREF potential at MIC1, MIC2 or PCBEEP, this can be achieved by choosing any suitable register settings that are not identical to those shown above. w WM9715L PD Rev 4.0 December 2007 57 ...
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... WM9715L AC97 DATA AND CONTROL INTERFACE INTERFACE PROTOCOL The WM9715Lhas a single AC’97 interface for both data transfer and control. The AC-Link uses 5 wires: • SDATAIN (pin 8) carries data from the WM9715L to the controller • SDATAOUT (pin 5) carries data from the controller to the WM9715L • ...
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... DATA SETUP AND HOLD Figure 18 Data Setup and Hold (50pF External Load) Note: Setup and hold times for SDATAIN are with respect to the AC’97 controller, not the WM9715L. Setup to falling edge of BITCLK Hold from falling edge of BITCLK Output valid delay from rising edge of ...
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... Incoming signals (from the AC’97 controller to the WM9715L) SDATAOUT rise time SDATAOUT fall time SYNC rise time SYNC fall time Outgoing signals (from the WM9715L to the AC’97 controller) BITCLK rise time BITCLK fall time SDATAIN rise time SDATAIN fall time AC-LINK POWERDOWN ...
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... Figure 22 Warm Reset Timing SYNC active high pulse width SYNC inactive to BITCLK startup delay w t RST_LOW BITCLK PARAMETER SYMBOL PARAMETER SYMBOL t t RST2CLK MIN TYP t 1.0 RST_LOW t 162.8 RST2CLK MIN TYP 1.3 SYNC_HIGH t 162.4 RST2CLK PD Rev 4.0 December 2007 WM9715L MAX UNIT µs ns MAX UNIT µ ...
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... AUXDACSLT 66h- Vendor Reserved 74h 76h Digitiser Reg 1 POLL 78h Digitiser Reg 2 PRP PNDN 7Ah Digitiser Read Back 7Ch Vendor ID1 7Eh Vendor ID2 Table 43 WM9715L Register Map SE3 SE2 SE1 SE0 ID9 ID8 ID7 LOUT2 Volume ...
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... Indicates that the WM9715L has a headphone output Indicates that the WM9715L does not support simulated stereo Indicates that the WM9715L supports bass and treble control Indicates that the WM9715L does not support modem functions Indicates that the WM9715L does not have a dedicated microphone ADC DEFAULT 1 (mute) Mutes LOUT2 and ROUT2 ...
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... WM9715L Register 08h controls the bass and treble response of the left and right audio DAC (but not AUXDAC). REG BIT LABEL ADDR 08h 11:8 BASS 6 DAT 4 TC 3:0 TRBL Register 0Ah controls the analogue input pin PCBEEP. REG BIT LABEL ADDR ...
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... Enables 20dB gain boost for ADC to phone mixer path 000 (mic) Selects left ADC signal source 000 (mic) Selects right ADC signal source DESCRIPTION DESCRIPTION DESCRIPTION DESCRIPTION DESCRIPTION PD Rev 4.0 December 2007 WM9715L REFER TO Auxiliary DAC REFER TO Audio Mixers, Side Tone Control REFER TO Analogue Audio Outputs REFER TO ...
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... RMU 14 GRL 13:8 RECVOLL GRR 5:0 RECVOLR Register 20h is a “general purpose” register as defined by the AC’97 specification. Only two bits are implemented in the WM9715L. REG BIT LABEL DEFAULT ADDR 20h 13 3DE 0 (OFF (OFF) Register 22h controls 3D stereo enhancement for the audio DACs. ...
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... PR1 0 ADC inverse of PR0 Note: PR6 to PR0 default the PWRUP pin is held high during reset, otherwise they default to 0. Register 28h is a read-only register that indicates to the driver which advanced AC’97 features the WM9715L supports. REG BIT LABEL DEFAULT ...
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... DEFAULT 0 Validity bit; ‘0’ indicates frame valid, ‘1’ indicates frame not valid 0 Indicates that the WM9715L does not support double rate SPDIF output (read-only) 10 Indicates that the WM9715L only supports 48kHz sampling on the SPDIF output (read-only) 0 Generation level; programmed as required by user 0000000 Category code ...
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... Selects analogue bias for lowest power, depending on AVDD supply. 0X=3.3V, 10=2.5V, 11=1.8V Selects source of SPDIF data. 0=from SDATAOUT, 1= from audio ADC Disables ADC high-pass filter Enables thermal sensor Selects time slots for stereo ADC data. 00=slots 3 and 4, 01=7/8, 10=6/9, 11=10/11 WM9715L REFER TO Interrupt Control REFER TO Battery Alarm Power Management N/A ...
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... Selects time slot for readback of touchpanel data Selects mode of operation. 00=OFF, 01=pen detect with wake-up, 10=pen detect without wake-up, 11=running Selects wake-up mode. 0=AC-Link only, 1=AC-Link and WM9715L auto-wake-up Selects 4-wire or 5-wire touchpanel Selects when touchpanel measurements take place. 0=always, 1=only when pen is down Controls data readback from register 7Ah ...
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... LABEL DEFAULT ADDR 7Ch 15:8 F7:0 57h 7:0 S7:0 4Dh 7Eh 15:8 T7:0 4Ch 7:0 REV7:0 12h w DESCRIPTION ASCII character “W” for Wolfson ASCII character “M” ASCII character “L” Part family identifier WM9715L REFER TO Intel’s AC’97 Component Specification, Revision 2.2, page 50 PD Rev 4.0 December 2007 71 ...
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... WM9715L APPLICATIONS INFORMATION RECOMMENDED EXTERNAL COMPONENTS Figure 23 External Components Diagram w Production Data PD Rev 4.0 December 2007 72 ...
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... Pull-up resistor, ensures that all circuit blocks are OFF by default AC’97 master clock frequency. A bias resistor is not required but if connected will not affect operation if the value is large (above 1MΩ (2π x 10.1kΩ x 1µ WM9715L PD Rev 4.0 December 2007 73 ...
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... If the DC coupled output is connected to the line- grounded piece of equipment, then OUT3 becomes short-circuited. Although the built-in short circuit protection will prevent any damage to the WM9715L, the audio signal will not be transmitted properly. • OUT3 cannot be used for another purpose ...
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... GPIO pin on the system CPU. Depending on the state of the switch, the GPIO pin is either grounded or high (due to a pull-up resistor). Whenever the CPU detects a change in the GPIO logic level, it should update the WM9715L registers to enable / disable the appropriate analogue outputs. COMBINED HEADSET / SINGLE-ENDED EAR SPEAKER Instead of a BTL ear speaker, a single-ended ear speaker can also be used, as shown below ...
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... WM9715L PACKAGE DIMENSIONS FL: 48 PIN QFN PLASTIC PACKAGE EXPOSED GROUND PADDLE BOTTOM VIEW (A3) SIDE VIEW C SEATING PLANE W (A3 Exposed lead Half etch tie bar Symbols Dimensions (mm) MIN NOM A 0.80 0. 0.02 A3 0.20 REF b 0.18 0.25 D 7.00 BSC D2 5.00 5.15 E 7.00 BSC E2 5.00 5.15 e 0.5 BSC G 0 ...
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... Wolfson is not liable for any such representations, warranties or liabilities or for any reliance placed thereon by any person. ADDRESS: Wolfson Microelectronics plc 26 Westfield Road Edinburgh EH11 2QB United Kingdom Tel :: +44 (0)131 272 7000 Fax :: +44 (0)131 272 7001 Email :: sales@wolfsonmicro.com w WM9715L PD Rev 4.0 December 2007 77 ...