WM9712LGEFL/V Wolfson Microelectronics, WM9712LGEFL/V Datasheet
WM9712LGEFL/V
Specifications of WM9712LGEFL/V
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WM9712LGEFL/V Summary of contents
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... auxiliary ADC inputs • 1.8V to 3.6V supplies • 7x7mm QFN APPLICATIONS • Personal Digital Assistants (PDA) • Smartphones • Handheld and Tablet Computers http://www.wolfsonmicro.com/enews/ WM9712L Production Data, August 2006, Rev 4.5 Copyright ©2006 Wolfson Microelectronics plc. ...
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WM9712L 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 ...
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Production Data PRINCIPLE OF OPERATION - FIVE-WIRE TOUCHPANEL........................................ 40 CONTROLLING THE TOUCHPANEL DIGITISER ....................................................... 42 AUXILIARY ADC INPUTS ....................................................................................47 BATTERY MEASUREMENT USING THE BMON/AUX3 PIN ....................................... 47 BATTERY ALARM AND ANALOGUE COMPARATORS ....................................48 GPIO AND INTERRUPT CONTROL ....................................................................51 AC97 DATA ...
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... XTLIN 2 XTLOUT 3 DGND1 4 SDATAOUT 5 WM9712L BITCLK 6 QFN DGND2 7 SDATAIN 8 DCVDD 9 SYNC 10 RESETB 11 WIPER / AUX4 ORDERING INFORMATION DEVICE TEMP. RANGE WM9712LGEFL/V -25 to +85 WM9712LGEFL/RV -25 to +85 Note: Reel quantity = 2,200 ROUT2 35 LOUT2 34 SPKGND 33 MONOOUT 32 CAP2 31 BMON / AUX3 30 COMP2 / AUX2 29 COMP1 / AUX1 28 MICBIAS 27 VREF 26 AGND ...
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Production Data PIN DESCRIPTION PIN NAME 1 DBVDD 2 XTLIN 3 XTLOUT 4 DGND1 5 SDATAOUT 6 BITCLK 7 DGND2 8 SDATAIN 9 DCVDD 10 SYNC 11 RESETB 12 WIPER / AUX4 13 TPVDD 14 X+/BR 15 Y+/TR 16 X-/TL ...
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WM9712L 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 ...
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Production Data ELECTRICAL CHARACTERISTICS AUDIO OUTPUTS Test Conditions DBVDD=3.3V, DCVDD = 3.3V, AVDD=HPVDD=SPKVDD =3.3V, T otherwise stated. PARAMETER SYMBOL DAC to Line-Out (HPOUTL/R or MONOOUT with 10kΩ / 50pF load) Full-scale output Signal to Noise Ratio (A-weighted) Total Harmonic Distortion ...
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WM9712L 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, ...
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Production Data TOUCHPANEL AND AUXILIARY ADC Test Conditions DBVDD=3.3V, DCVDD = 3.3V, AVDD = TPVDD = 3.3V, T PARAMETER Input Pins X+, X-, Y+, Y-, WIPER/AUX4, COMP1/AUX1, COMP2/AUX2 and BMON/AUX3 Input Voltage Input leakage current ADC Resolution Differential Non-Linearity Error ...
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WM9712L 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 = ...
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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 ...
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WM9712L POWER CONSUMPTION The power consumption of the WM9712L depends on the following factors. • 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 ...
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Production Data DEVICE DESCRIPTION INTRODUCTION The WM9712L 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 GPIO functions, all controlled through a single ...
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WM9712L AUDIO PATHS OVERVIEW 20h:7 (Loopback) L Slot 3 ADC Left 1 Tone and 3D Left Channel 08h / 22h / 18 Bit DAC AC Link 0 20h:13 (3DE) 10h:12-8 00000 = +12dB 11111 = -34.5dB LINEINL to SPKR MIXER ...
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Production Data AUDIO INPUTS The following sections give an overview of the analogue audio input pins and their function. For more information on recommended external components, please refer to the “Applications Information” section. LINE INPUT The LINEINL and LINEINR inputs ...
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WM9712L 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 ...
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Production Data CAP2 Figure 2 Microphone Bias Schematic PHONE INPUT Pin 20 (PHONE mono, line level input designed to connect to the receive path of a telephony device. The pin connects directly to the record selector for phone ...
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WM9712L 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 ...
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Production Data AUDIO ADC The WM9712L has a stereo sigma-delta ADC to digitize audio signals. The ADC achieves high quality audio recording at low power consumption. The ADC sample rate can be controlled by writing to a control register (see ...
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WM9712L 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 ...
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Production Data RECORD GAIN The amplitude of the signal that enters the audio ADC is controlled by the Record PGA (Programmable Gain Amplifier). The PGA gain can be programmed either by writing to the Record Gain register the ...
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WM9712L AUTOMATIC LEVEL CONTROL The WM9712L 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 ...
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Production Data REGISTER ADDRESS 62h ALC / Noise Gate Control 60h ALC Control Table 9 ALC Control w BIT LABEL DEFAULT 15:14 ALCSEL 00 ALC function select (OFF ALC off (PGA gain set by register Right ...
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WM9712L MAXIMUM GAIN The MAXGAIN register sets the maximum gain value that the PGA can be set to whilst under the control of the ALC. This has no effect on the PGA when ALC is not enabled. PEAK LIMITER To ...
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Production Data AUDIO DACS STEREO DAC The WM9712L has a stereo sigma-delta DAC that achieves high quality audio playback at low power consumption. Digital tone control, adaptive bass boost and 3-D enhancement functions operate on the digital audio data before ...
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WM9712L TONE CONTROL / BASS BOOST The WM9712L 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 ...
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Production Data 3D STEREO ENHANCEMENT The 3D stereo enhancement function artificially increases the separation between the left and right channels by amplifying the (L-R) difference signal in the frequency range where the human ear is sensitive to directionality. The programmable ...
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WM9712L 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 ...
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Production Data 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 ...
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WM9712L EAR SPEAKER OUTPUT – OUT3 Pin 37 (OUT3) has a buffer that can drive load impedances down to 16Ω. It can be used to: • Drive an ear speaker (phone receiver). The speaker can be connected differentially between OUT3 ...
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Production Data 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 ...
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WM9712L PHONE OUTPUT (MONOOUT) The MONOOUT output (pin 33) is intended for connection to the TX side of a wireless chipset. The signal is generated in a dedicated mono mixer not necessarily a mono mix of the stereo ...
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Production Data JACK INSERTION AND AUTO-SWITCHING In a phone application, a BTL ear speaker may be connected across OUT3 and HPOUTL, and a stereo headphone on HPOUTL and HPOUTR. Typically, only one of these two output devices is used at ...
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WM9712L DIGITAL AUDIO (SPDIF) OUTPUT The WM9712L supports the SPDIF standard using pin 47 as its output. Note that pin 47 can also be used as a GPIO pin. The GE5 bit (register 56h, bit 5) selects between GPIO and ...
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Production Data AUDIO MIXERS MIXER OVERVIEW The WM9712L 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. ...
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WM9712L 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”) ...
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Production Data VARIABLE RATE AUDIO / SAMPLE RATE CONVERSION By using an AC’97 Rev2.2 compliant audio interface, the WM9712L can record and playback at all commonly used audio sample rates, and offer full split-rate support (i.e. the DAC, ADC and ...
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WM9712L TOUCHPANEL INTERFACE The WM9712L 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 ...
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Production Data The principle of operation is illustrated below (Note: the illustrations assume that the top plate is used for X and the bottom plate for Y measurements, although the reverse is also possible). Figure 6 X Co-ordinate Measurement on ...
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WM9712L When the touchpanel is not being touched, no current flows in the circuit, and the PENDOWN signal is low. When the panel is touched with a pen or finger, current flows through R the comparator output goes high. The ...
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Production Data For an X co-ordinate measurement, the top left and bottom left corners of the touchpanel are grounded internally to the WM9712, while the top right and bottom right contacts are connected to TPVDD. The bottom plate becomes a ...
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WM9712L CONTROLLING THE TOUCHPANEL DIGITISER All touchpanel functions are accessed and controlled through the AC-Link interface. PHYSICAL CHARACTERISTICS The physical characteristics of the touchpanel interface are controlled through register 78, as shown below. REGISTER ADDRESS 78h Table 25 Touchpanel Digitiser ...
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Production Data INITIATION OF MEASUREMENTS The WM9712L touchpanel interface supports both polling routines and DMA (direct memory access) to control the flow of data from the touchpanel ADC to the host CPU polling routine, the CPU starts each ...
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WM9712L When COO is ‘0’, the WM9712L performs one type of measurement once (in polling mode) or continuously (in continuous mode). The co-ordinate mode (COO = ‘1’) makes it easier to obtain co-ordinate pairs rather than single co- ordinates. In ...
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Production Data If the SLEN bit is set to ‘1’, then the touchpanel data appears on the AC-Link slot selected by the SLT control bits, as shown below. The Slot 0 ‘tag’ bit corresponding to the selected time slot is ...
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WM9712L 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 NOT intended for touchpanel digitisation. There are several side-effects when DEL is set ...
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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 WM9712L has four pins that can be used as auxiliary ADC ...
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WM9712L 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 ...
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Production Data The WM9712L 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 ...
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WM9712L COMP2 DELAY FUNCTION COMP2 has an optional delay function for use when the input signal is noisy. When COMP2 triggers and the delay is enabled (i.e. COMP2DEL is non-zero), then GPIO bit 14 does not change state immediately, and ...
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Production Data GPIO AND INTERRUPT CONTROL The WM9712L has five GPIO pins that operate as defined in the AC’97 Revision 2.2 specification. Each GPIO pin can be set input output, and has corresponding bits ...
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WM9712L GPIO BIT 6- Table 37 GPIO Bits and Pins w SLOT12 TYPE PIN NO. BIT 5 GPIO Pin 44 6 GPIO Pin 45 7 GPIO Pin 46 8 GPIO ...
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Production Data The properties of the GPIOs are controlled through registers 4Ch to 52h, as shown below. REGISTER ADDRESS 4Ch 4Eh 50h 52h 54h Table 38 GPIO Control The following procedure is recommended for handling interrupts: When the controller receives ...
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WM9712L REGISTER ADDRESS 56h GPIO pins function select Table 39 Using GPIO Pins for Non-GPIO Functions REGISTER ADDRESS 58h Additional Functional Control Table 40 Additional Functionality for GPIO Pins w BIT LABEL DEFAULT 2 GE2 1 GPIO2 / IRQ output ...
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Production Data POWER MANAGEMENT The WM9712L includes the standard power down control register defined by the AC’97 specification (register 26h). Additionally, it also allows more specific control over the individual blocks of the device through register 24h. Each particular circuit ...
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WM9712L REGISTER ADDRESS 24h Additional power down control Note: When analogue inputs or outputs are disabled, they are internally connected to VREF through a large resistor (VREF=AVDD/2 except in OFF mode, when VREF itself is disabled). This maintains the potential ...
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Production Data LOW POWER STANDBY MODE If all the bits in registers 26h and 24h are set, then the WM9712L is in low-power standby mode and consumes very little current. A 1MΩ resistor string remains connected across AVDD to generate ...
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WM9712L AC97 DATA AND CONTROL INTERFACE INTERFACE PROTOCOL The WM9712Lhas a single AC’97 interface for both data transfer and control. The AC-Link uses 5 wires: • SDATAIN (pin 8) carries data from the WM9712L to the controller • SDATAOUT (pin ...
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Production Data INTERFACE TIMING Test Characteristics: DBVDD = 3.3V, DCVDD = 3.3V, DGND1 = DGND2 = 0V, T CLOCK SPECIFICATIONS Figure 17 Clock Specifications (50pF External Load) BITCLK frequency BITCLK period BITCLK output jitter BITCLK high pulse width (Note 1) ...
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WM9712L SIGNAL RISE AND FALL TIMES SDATAOUT Figure 19 Signal Rise and Fall Times (50pF External Load) Incoming signals (from the AC’97 controller to the WM9712L) SDATAOUT rise time SDATAOUT fall time SYNC rise time SYNC fall time Outgoing signals ...
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Production Data COLD RESET (ASYNCHRONOUS, RESETS REGISTER SETTINGS) RESETB Figure 21 Cold Reset Timing Note: For correct operation SDATAOUT and SYNC must be held LOW for entire RESETB active low period otherwise the device may enter test mode. See AC'97 ...
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WM9712L REGISTER MAP Note: Highlighted bits differ from the AC’97 specification (newly added for non-AC’97 function, or same bit used in a different way, or for another function) Reg Name 15 14 00h Reset 0 SE4 02h LOUT2/ROUT2 Volume MU ...
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... MONOOUT VOL w DESCRIPTION Indicates a codec from Wolfson Microelectronics Indicates 18 bits resolution for ADCs and DACs Indicates that the WM9712L supports bass boost Indicates that the WM9712L has a headphone output Indicates that the WM9712L does not support simulated stereo Indicates that the WM9712L supports bass and treble control ...
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WM9712L 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 ...
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Production Data Register 12h controls the output signal of the auxiliary DAC. REG BIT LABEL ADDR 12h 15 A2H 14:12 A2HVOL 11 A2S 10:8 A2SVOL 7 A2P 6:4 A2PVOL 0 AXE Register 14h controls the side tone paths. REG BIT ...
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WM9712L Register 1Ch controls the.recording gain. REG BIT LABEL ADDR 1Ch 15 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 ...
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Production Data Register 26h is for power management according to the AC’97 specification. Note that the actual state of many circuit blocks depends on both register 24h AND register 26h. REG BIT LABEL DEFAULT ADDR 14 PR6 see note 13 ...
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WM9712L Register 3Ah controls the SPDIF output. REG BIT LABEL ADDR 3Ah DRS 13:12 SPSR PRE 2 COPY 1 AUDIB 0 PRO Register 4Ch to 54h control the GPIO pins and virtual ...
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Production Data Register 58h controls several additional functions. REG BIT LABEL ADDR 58h 15:13 COMP2DEL 000 (no delay) 12 JIEN 0 11 FRC 0 10 SVD 0 (enabled) 3:2 DIE REV Indicates device revision. 00=Rev.A, 01=Rev.B, 10=Rev.C 1 WAKEEN 0 ...
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WM9712L Register 64h controls the input signal of the auxiliary DAC. REG BIT LABEL ADDR 64h 15 XSLE 14:12 AUXDACSLT 11:0 AUXDACVAL Registers 76h, 78h and 7Ah control the touchpanel interface. REG BIT LABEL ADDR 76h 15 POLL 0 14:12 ...
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Production Data APPLICATIONS INFORMATION RECOMMENDED EXTERNAL COMPONENTS DVDD AVDD GND AGND AC-LINK AVDD DVDD AGND GND Layout Notes C6, C9 C11 and C13 should be as close to the relative ...
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WM9712L RECOMMENDED COMPONENTS VALUES COMPONENT SUGGESTED REFERENCE VALUE 100nF 10uF C9 100nF C10 10uF C11 100nF C12 10uF C13 100nF C14 10uF C27 & C28 22pF C15 - C20 1uF C21 - C23 2.2uF ...
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Production Data AC-COUPLED HEADPHONE OUTPUT The circuit diagram below shows how to connect a stereo headphone to the WM9712L. WM9712L Figure 25 Simple Headphone Output Circuit Diagram The DC blocking capacitors C1 and C2 together with the load resistance determine ...
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WM9712L BTL LOUDSPEAKER OUTPUT LOUT2 and ROUT2 can differentially drive a mono 8Ω loudspeaker as shown below. WM9712L Figure 27 Speaker Output Connection (INV = 1) The right channel is inverted by setting the INV bit, so that the signal ...
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Production Data JACK INSERT DETECTION The circuit diagram below shows how to detect when a headphone or headset has been plugged into the headphone socket. It generates an interrupt, instructing the controller to enable HPOUTL and HPOUTR and disable OUT3. ...
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WM9712L PACKAGE DRAWING 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 ...
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... Production Data IMPORTANT NOTICE Wolfson Microelectronics plc (“Wolfson”) products and services are sold subject to Wolfson’s terms and conditions of sale, delivery and payment supplied at the time of order acknowledgement. Wolfson warrants performance of its products to the specifications in effect at the date of shipment. Wolfson reserves the right to make changes to its products and specifications or to discontinue any product or service without notice ...