ISO2-CMOS MT9196 Integrated Digital Phone Circuit (IDPC) Preliminary Information Features ISSUE 3 May 1995 • Programmable µ-Law/A-Law CODEC and Filters • Programmable CCITT (G.711)/sign-magnitude coding • Programmable transmit, receive and side-tone gains • Digital DTMF and single tone generation • Fully differential interface to handset transducers Description • Auxiliary analog interface • Interface to ST-BUS/SSI (compatible with GCI) • Serial microport control • Single 5 volt supply, low power operation • Anti-howl circuit for group listening speakerphone applications The MT9196 Integrated Digital Phone Circuit (IDPC) is designed for use in digital phone products. The device incorporates a built-in Filter/Codec, digital gain pads, DTMF generator and tone ringer. Complete telephony interfaces are provided for connecting to handset and speakerphone transducers. Internal register access is provided through a serial microport compatible with various industry standard micro-controllers. Ordering Information MT9196AE 28 Pin Plastic DIP MT9196AP 28 Pin Plastic LCC MT9196AS 28 Pin SOIC -40°C to +85°C Applications • Digital telephone sets • Wireless telephones • Local area communications stations VSSD VDD VSSA VSS SPKR VBias VRef Tone Generator Digital Gain &AAAA AAAAAAAA AAAAAAAA AAAAAAAAAAAA AAAAAAAA AAAAAA AAAA AAAAAAAA AAAA AAAA AAAA AAAA AA AAAA AAAA AAAA AAAA AAAA AAAA 21/ - 24dB AAAA AAAA AAAA AAAA AAAA AAAA A AAAA AAAA AAAA AAAA AAAA AAAA ∆3.0dB AAAAAAAAAA AAAA AAAA AAAAAAAA AAAAAAAA AAAAAAAAAAAAA AAAA AAAA AAAA Tx &AAAA Rx AAAA AAAA AAAAAAAA AAAA AAAA AAAAAAAA AAAAAAA AAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAA The device is fabricated in Mitel's ISO2-CMOS technology ensuring low power consumption and high reliability. Filter/Codec Gain AAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAAAAA AAA AAAA AAAA AAAA AAAA AAAA AAAA AAA AAAA AAAA AAAA AAAA AAAA AAAA AAA Encoder 7dB AAAA AAAA AAAA AAAA AAAA AAAA AAA AAAA AAAA AAAA AAAA AAAA AAAA AAA AAAA AAAA AAAA AAAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAA AAA AAAA AAAA AAAA AAAA AAAA AAAA AAA Decoder -7dB AAAA AAAA AAAA AAAA AAAA AAAA AAA AAAA AAAA AAAA AAAA AAAA AAAA AAAAAAAAAAAAAAAAAAAAAAAAAAA AAA AUXin AUXout MIC + MM+ Transducer Interface HSPKR + HSPKR SPKR + Din Timing Dout STB/F0i Flexible Digital Interface SPKR - ST-BUS C&D Channels CLOCKin Serial Microport XSTL2 WD PWRST IC IRQ CS DATA1 DATA2 SCLK Figure 1 - Functional Block Diagram 7-127 MT9196 4 3 2 1 28 27 26 5 25 24 6 23 7 22 8 21 9 20 10 19 11 12 13 14 15 16 17 18 AUXout VSS SPKR SPKR+ SPKRHSPKR+ HSPKRVDD WD IRQ Dout Din STB/F0i CLOCKin XSTAL2 PWRST IC VSSD CS SCLK DATA1 DATA2 M+ MVSSA MIC+ AUXin VRef VBias Preliminary Information 28 PIN PLCC MM+ VBias VRef PWRST IC VSSD CS SCLK DATA1 DATA2 WD IRQ Dout 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 VSSA MIC+ AUXin AUXout VSS SPKR SPKR+ SPKRHSPKR+ HSPKRVDD XSTAL2 CLOCKin STB/F0i Din 28 PIN SOIC/PDIP Figure 2 - Pin Connections Pin Description Pin # Name 1 M- Inverting Microphone (Input). Inverting input to microphone amplifier from the handset microphone. 2 M+ Non-Inverting Microphone (Input). Non-inverting input to microphone amplifier from the handset microphone. 3 VBias Bias Voltage (Output). (VDD/2) volts is available at this pin for biasing external amplifiers. Connect 0.1 µF capacitor to VSSA. 4 VRef Reference voltage for codec (Output). Nominally [(VDD/2)-1.5] volts. Used internally. Connect 0.1 µF capacitor to VSSA. 5 PWRST 6 IC 7 VSSD 8 CS 9 SCLK Serial Port Synchronous Clock (Input). Data clock for microport. TTL level compatible. 10 DATA1 Bidirectional Serial Data. Port for microprocessor serial data transfer. In Motorola/National mode of operation, this pin becomes the data transmit pin only and data receive is performed on the DATA2 pin. TTL level compatible input levels. 11 DATA2 Serial Data Receive. In Motorola/National mode of operation, this pin is used for data receive to the IDPC. In Intel mode, serial data transmit and receive are performed on the DATA1 pin and DATA2 is disconnected. Input level TTL compatible. 12 WD Watchdog (Output). Watchdog timer output. Active high. 13 IRQ Interrupt Request (Open Drain Output). Low true interrupt output to microcontroller. 14 Dout Data Output. A tri-state digital output for 8 bit wide channel data being sent to the Layer 1 device. Data is shifted out via this pin concurrent with the rising edge of BCL during the timeslot defined by STB, or according to standard ST-BUS timing. 15 Din Data Input. A digital input for 8 bit wide channel data received from the Layer 1 device. Data is sampled on the falling edge of BCL during the timeslot defined by STB, or according to standard ST-BUS timing. Input level is CMOS compatible. 7-128 Description Power-up Reset (Input). CMOS compatible input with Schmitt Trigger (active low). Internal Connection. Tie externally to VSS for normal operation. Digital Ground. Nominally 0 volts. Chip Select (Input). This input signal is used to select the device for microport data transfers. Active low. TTL level compatible. MT9196 Preliminary Information Pin Description (continued) Pin # Name 16 STB/F0i 17 CLOCKin Clock Input. The clock provided to this input is used by the internal phone functions. In STBUS mode this is the C4i input. In SSI synchronous mode, this is the Bit Clock input. In SSI-asynchronous mode this is an asynchronous 4 MHz Master Clock input. 18 XSTL2 19 VDD Description Data Strobe/Frame Pulse (Input). For SSI mode this input determines the 8 bit timeslot used by the device for both transmit and receive data. This active high signal has a repetition rate of 8 kHz. Standard frame pulse definitions apply in ST-BUS mode. CMOS level compatible input. Crystal Input (4.096 MHz). Used in conjunction with the CLOCKin pin to provide the master clock signal via external crystal. Positive Power Supply (Input). Nominally 5 volts. 20 HSPKR- Inverting Handset Speaker (Output). Output to the handset speaker (balanced). 21 HSPKR+ Non-Inverting Handset Speaker (Output). Output to the handset speaker (balanced). 22 SPKR- Inverting Speaker (Output). Output to the speakerphone speaker (balanced). 23 SPKR+ Non-Inverting Speaker (Output). Output to the speakerphone speaker (balanced). 24 VSSSPKR Power Supply Rail for Speaker Driver. Nominally 0 Volts. 25 AUXout Auxiliary Port (Output). Access point to the D/A (analog) signals of the receive path as well as to the various analog inputs. 26 AUXin Auxiliary Port (Input). An analog signal may be fed to the filter/codec transmit section and various loopback paths via this pin. No external anti-aliasing is required. 27 MIC+ Non-inverting on-hook answer back Microphone (Input). Microphone amplifier noninverting input pin. 28 VSSA Analog Ground (Input). Nominally 0 V. 7-129 MT9196 Overview The functional block diagram of Figure 1 depicts the main operations performed by the MT9196 IDPC. Each of these functional blocks will be described individually in the sections to follow. This overview will describe some of the end-user features which may be implemented as a direct result of the level of integration found within the IDPC. The main feature required of a digital telephone is to convert the digital Pulse Code Modulated (PCM) information, being received by the telephone set, into an analog electrical signal. This signal is then applied to an appropriate audio transducer such that the information is finally converted into intelligible acoustic energy. The same is true of the reverse direction where acoustic energy is converted first into an electrical analog and then digitized (into PCM) before being transmitted from the set. Along the way if the signals can be manipulated, either in the analog or the digital domains, other features such as gain control and signal generation may be added. Finally, most electro-acoustic transducers (loudspeakers) require a large amount of power if they are to develop an acoustic signal. The inclusion of audio amplifiers to provide this power is required. The IDPC features complete Analog/Digital and Digital/Analog conversion of audio signals (Filter/ CODEC) and an analog interface to electro-acoustic devices (Transducer Interface). Full programmability of the receive path and side-tone gains is available to set comfortable listening levels for the user. Transmit path gain control is available for setting nominal transmit levels into the network. A digital, anti-feedback circuit permits both the handset microphone and the speaker-phone speaker to be enabled at the same time for group listening applications. This anti-feedback circuit limits the total loop gain there by preventing a singing condition from developing. Signalling in digital telephone systems, behind the PBX or standard ISDN applications, is handled on the D-channel and generally does not require DTMF tones. Locally generated tones, in the set, however, can be used to provided “comfort tones” or “key confirmation” to the user, similar to the familiar DTMF tones generated by conventional phones during initial call set-up. Also, as the network slowly evolves from the dial pulse/DTMF methods to the DChannel protocols it is essential that the older methods be available for backward compatibility. As an example, once a call has been established (i.e., from your office to your home) using the D-Channel Preliminary Information signalling protocol it may be necessary to use inband DTMF signalling to manipulate your personal answering machine in order to retrieve messages. Thus the locally generated tones must be of network quality. The IDPC can generate the required tone pairs as well as single tones to accommodate any inband signalling requirement. Each of the programmable parameters within the functional blocks is accessed through a serial microcontroller port compatible with Intel MCS-51 ®, Motorola SPI® and National Semiconductor Microwire® specifications. Functional Description In this section each of the functional blocks within IDPC is described along with all of the associated control/status bits. Each time a control/status bit(s) is described it is followed by the address register where it will be found. The reader is referred to the section titled 'Register Summary' for a complete listing of all address registers, the control/status bits associated with each register and a definition of the function of each control/status bit. The Register Summary is useful for future reference of control/ status bits without the need to locate them in the text of the functional descriptions. Filter/CODEC The Filter/CODEC block implements conversion of the analog 3.3 kHz speech signals to/from the digital domain compatible with 64 kb/s PCM B-Channels. Selection of companding curves and digital code assignment are register programmable. These are CCITT G.711 A-law or µ-Law, with true-sign/ Alternate Digit Inversion or true-sign/Inverted Magnitude coding, respectively. Optionally, signmagnitude coding may also be selected for proprietary applications. The Filter/CODEC block also implements transmit and receive audio path gains in the analog domain. These gains are in addition to the digital gain pad section and provide an overall path gain resolution of 1.0dB. A programmable gain, voice side-tone path is also included to provide proportional transmit speech feedback to the handset receiver. Figure 3 depicts the nominal half-channel and side-tone gains for the IDPC. Intel® and MCS-51® are registered trademarks of Intel Corporation Motorola® and SPI® are registered trademarks of Motorola Corporation National® and Microwire® are trademarks of National Semiconductor Corporation 7-130 MT9196 Preliminary Information On PWRST (pin 5) the Filter/CODEC defaults such that the side-tone path, dial tone filter and 400 Hz transmit filter are off, all programmable gains are set to 0dB and CCITT µ-Law is selected. Further, the Filter/CODEC is powered down due to the control bits of the Path Control Registers (addresses 12h and 13h) being reset. capacitor must be connected from V Bias to analog ground at all times. Likewise, although V Ref may only be used internally, a 0.1 µF capacitor from the V Ref pin to ground is required at all times. The analog ground reference point for these two capacitors must be physically the same point. To facilitate this the VRef and VBias pins are situated on adjacent pins. The internal architecture is fully differential to provide the best possible noise rejection as well as to allow a wide dynamic range from a single 5 volt supply design. This fully differential architecture is continued into the Transducer Interface section to provide full chip realization of these capabilities for the handset and loudspeaker functions. The transmit filter is designed to meet CCITT G.714 specifications. The nominal gain for this filter path is 0 dB (gain control = 0 dB). Gain control allows the output signal to be increased up to 7 dB. An antialiasing filter is included. This is a second order lowpass implementation with a corner frequency at 25 kHz. Attenuation is better than 32 dB at 256 kHz and less than 0.01 dB within the passband. A reference voltage (VRef), for the conversion requirements of the CODEC section, and a bias voltage (VBias), for biasing the internal analog sections, are both generated on-chip. V Bias is also brought to an external pin so that it may be used for biasing external gain plan setting amplifiers. A 0.1 µF SERIAL PORT DIGITAL GAIN & TONES FILTER/CODEC An optional 400Hz high-pass function may be included into the transmit path by enabling the Tfhp bit in the Control Register 1 (address 0Eh). This option allows the reduction of transmitted background noise such as motor and fan noise. TRANSDUCER INTERFACE Handset Receiver (150Ω) -6.1 dB or -3.6 dB HSPKR + Receiver Driver Receive PCM Din Receive Filter Gain 0 to -7 dB (1 dB steps) -24 to +21 dB (3dB steps) Side-tone -9.96 to +9 96dB (3.32 dB steps) DTMF, Tone Ringer -11 dB PCM Dout -24 to +21 dB (3 dB steps) Transmit Filter Gain 0 to +7 dB (1 dB steps) Transmit -6 dB 75 Speaker Phone Driver 0 dB SPKR + SPKR - Speakerphone Speaker (40Ω nominal) 34Ω min) 0/+8dB AAAAAAAAAAAAAAAAA +8 to -20dB (4 dB steps) Auxiliary Out Driver -12 dB RINGER 0 to -28 dB (4 dB steps) Transmit Gain -0.37 dB or 8.93 dB Digital Domain 75 HSPKR - Transmit Gain 6.37 dB AUXout 5 dB AUXin AUX input 5 dB MIC+ M U X H/F answerback mic M + Transitter microphone M- Analog Domain Internal To Device External To Device Figure 3 - Audio Gain Partitioning 7-131 MT9196 Preliminary Information The receive filter is designed to meet CCITT G.714 specifications. The nominal gain for this filter path is 0 dB (gain control = 0dB). Gain control allows the output signal to be attenuated up to 7 dB. Filter response is peaked to compensate for the sinx/x attenuation caused by the 8 kHz sampling rate. The Rx filter function can be altered by enabling the Dial EN control bit in Control Register 1 (address 0Eh). This causes another low-pass function to be added with a 3 dB point at 1000 Hz. This function is intended to improve the sound quality of digitally generated dial tone received as PCM. Side-tone is derived from the Tx filter before the LP/ HP filter section and is not subject to the gain control of the Tx filter section. Side-tone is summed into the receive handset transducer driver path after the Rx filter gain control section so that Rx gain adjustment will not affect side-tone levels. The side-tone path may be enabled/disabled with the Voice sidetone bit located in the Receive Path Control Register (address 13h). Transmit and receive filter gains are controlled by the TxFG0-TxFG2 and RxFG0-RxFG2 control bits, respectively. These are located in the FCODEC Control Register 1 (address 0Ah). Transmit filter gain is adjustable from 0 dB to +7 dB and receive filter gain from 0 dB to -7 dB, both in 1 dB increments. Side-tone filter gain is controlled by the STG 0-STG2 control bits located in the FCODEC Control Register 2 (address 0Bh). Side-tone gain is adjustable from -9.96 dB to +9.96 dB in 3.32 dB increments. Companding law selection for the Filter/CODEC is provided by the A/µ companding control bit while the coding scheme is controlled by the sign-mag/ CCITT control bit. Both of these reside in Control Register 2 (address 0Fh). Table 1 illustrates these choices. Code Sign/ Magnitude CCITT (G.711) µ-Law The Digital gain and Tone generator block is located, functionally, between the serial FDI port and the Filter/CODEC block. Its main function is to provide digital gain control of the transmit and receive audio signals and to generate digital patterns for DTMF and tone ringer signals. Gain Control Gain control is performed on linear code for both the receive and the transmit PCM. Gain control is set via the Digital Gain Control Register at address 19h. Gain, in 3.0 dB increments, is available within a range of +21.0 dB to -24 dB. DTMF Generator The digital DTMF circuit generates a dual sine-wave pattern which may be routed into the receive path as comfort tones or into the transmit path as network signalling. In both cases the digitally generated signal will undergo gain adjustment as programmed into the transmit and receive gain control registers. Gain control is assigned automatically as functions are selected via the transmit and receive path control registers. The composite signal output level in the transmit direction is -4 dBm0 (µ-Law) and -10 dBm0 (A-law) with programmable gains at zero dB. Pre-twist of 2.0 dB is incorporated into the composite signal resulting in a low tone output level of -8.12 dBm0 and a high group level of -6.12dBm0 (for µ-Law, 6 dB lower for A-Law). Note that these levels will be influenced by the Anti-Howling circuit when it is enabled (see AntiHowling section for more details). DTMF side-tone levels are set to -28 dBm0 from the generator circuit. Other receive path gains must be included when calculating the analog output signal levels. Adjustments to these levels may be made by altering the settings of the Gain Control register (address 19h). A-Law + Full Scale 1111 1111 1000 0000 1010 1010 + Zero 1000 0000 1111 1111 1101 0101 -Zero (quiet code) 0000 0000 0111 1111 0101 0101 - Full Scale 0111 1111 0000 0000 0010 1010 Table 1 The Filter/CODEC autonull circuit ensures that transmit PCM will contain no more than ±1 bit of offset due to internal circuitry. 7-132 Digital Gain and Tone Generation The frequency of the low group tone is programmed by writing an 8-bit coefficient into the Low Tone Coefficient Register (address 1Ah) while the high group tone frequency uses the 8-bit coefficient programmed into the High Tone Coefficient Register (address 1Bh). Both coefficients are determined by the following equation: Frequency (in Hz) = 7.8125 x COEFF Where COEFF is an integer between 0 and 255. Frequency resolution is 7.8125 Hz in the range 0 to 1992 Hz. MT9196 Preliminary Information Low and high tones are enabled individually via the LoEn and HiEN control bits (DTMF/Ringer Control Register, address 18h). This not only provides control over dual tone generation but also allows single tone generation using either of the enable bits and its associated coefficient register. After programming and enabling the tone generators as described, selection of transmit and/or receive path destinations are carried out via the Path Control Registers (see Path Control section). In addition receive sidetone DTMF must be selected via the DTMF StEN bit (DTMF/Tone ringer Register, address 18h) so that it replaces the received PCM in the Rx Filter path. Frequency (Hz) COEFF Actual Frequency % Deviation 697 59h 695.3 -.20% 770 63h 773.4 +.40% 852 6Dh 851.6 -.05% 941 79h 945.3 +.46% 1209 9Bh 1210.9 +.20% 1336 ABh 1335.9 1477 BDh 1633 D1h Both coefficients are determined by the following equation: COEFF = [32000/Frequency (Hz)] - 1 where COEFF is an integer between 1 and 255. This produces frequencies between 125 - 16000 Hz with a non-linear resolution. The ringer program switches between these two frequencies at a 5 Hz or 10 Hz rate as selected by the WR bit in the DTMF/Tone ringer register (address 18h). Anti-Howl IDPC includes an Anti-Howling circuit plus speaker gain control circuit to allow for group listening operation. Although this is the main function of the circuit there are additional modes in which it may be used as defined by the MS1 and MS0 control bits (address 1Ch). .00% MS1 0 0 1 MS0 0 1 0 1476.6 -.03% 1 1 1632.8 -.01% Table 2 - DTMF Frequencies DTMF Signal to distortion: The sum of harmonic and noise power in the frequency band from 50 Hz to 3500 Hz is typically more than 30 dB below the power in the tone pair. All individual harmonics are typically more than 40 dB below the level of the low group tone. Table 2 gives the standard DTMF frequencies, the coefficient required to generate the closest frequency, the actual frequency generated and the percent deviation of the generated tone from the nominal. Tone Ringer A dual frequency squarewave ringing signal may be applied to the handsfree speaker driver to generate a call alerting signal. To enable this mode the Ring En bit (address 18h) must be set as well as the ringer function to the loudspeaker via the Receive Path Control Register (address 13h). Ring En is independent of the DTMF enable control bits (see Lo EN and Hi EN). Since both functions use the same coefficient registers they are not usually enabled simultaneously. The digital tone generator uses the values programmed into the low and high Tone Coefficient Registers (addresses 1Ah and 1Bh) to generate two different squarewave frequencies. Operational Mode Tx noise reduction (squelch) Rx noise reduction (squelch) switched loss group listening (anti-howling) Tx/Rx switched loss The circuit is enabled by setting the Anti-howl Enable bit (address 1Ch) and selecting the required operational mode (MS0 & MS1) as described. For all modes of operation the switching levels and inserted loss are programmed as follows. Switching decisions are made by comparing either the transmit or the receive signal level to threshold levels stored in the High Threshold Register (address 1Dh) and the Low Threshold Register (address 1Eh). Threshold data is encoded in PCM sign-magnitude format excluding the sign bit. For example; THh0 - THh3 encode the PCM step number while THh4 - THh6 encode the PCM chord number for the high threshold. Similarily for the THl0 - THl6 bits of the low threshold. The difference between the high and low threshold levels provides the circuit with hysteresis to prevent uncontrolled operation. The low level threshold must never be programmed to a value higher than the one stored in the high level threshold. If this occurs the circuit will become unstable. Loss is implemented, in the chosen path, by subtracting the value set by the Pad0 - Pad3 control bits from the appropriate gain value set by the RxG0 - RxG3 or TxG0 - TxG3 control bits (see Digital Gain 7-133 MT9196 Preliminary Information Register, address 19h). The minimum digital gain is limited to -24 dB regardless of the mathematical result of this operation. The path without loss reverts to the gain value programmed into the Digital Gain Register. The magnitude of the switched loss defaults to 12 dB on power up but can be programmed to between 0 and 21 dB using the Pad0 - Pad2 control bits (address 1Ch). Pad2 0 0 0 0 1 1 1 1 Pad1 0 0 1 1 0 0 1 1 Pad0 0 1 0 1 0 1 0 1 Attenuation (dB) 0 3 6 9 12 15 18 21 Switched Loss for Group Listening (anti-howling) Group listening is defined as a normal handset conversation with received speech also directed to the loudspeaker for third party observation. In this mode, if the handset microphone is moved into close proximity of the loudspeaker a feedback path will occur resulting in a singing connection. To prevent this the anti-howling circuit introduces a switched loss into either the transmit or receive paths dependent upon the transmit path speech activity. Loss switching is determined by comparing the signal level in the transmit path with the high level threshold stored at address 1Dh. When the transmit signal level exceeds this threshold the programmed loss is switched from the transmit path to the receive path. Once switching has occurred the transmit signal level is then compared to a low level threshold stored at address 1Eh. When the transmit signal level falls below this threshold the programmed loss is switched from the received path back to the transmit path and comparison reverts back to the high threshold level. Since the received digital gain control is used to set the listening level of the received speech, for both handset receiver and loudspeaker, it is necessary to provide additional gain in the loudspeaker path so that its receive level can be controlled independently from the receiver output. The Gain0 to Gain3 control bits (address 0Bh) are used to boost the loudspeaker output to a comfortable listening level for the third parties in group listening. Generally the Gain3 bit should be set to logic 1 in this mode. This increases the gain programmed via the Gain0 - Gain2 bits by a factor of 8 dB. In group listening a speaker gain setting of 4 to 16 dB will be required to set a 7-134 comfortable group listening level after the handset user has adjusted their listening level as required. Since the anti-howling circuit has dynamic control over the transmit and receive gain control registers, it is recommended that this function be turned off momentarily when DTMF tone generation is required. This will ensure that the proper transmit levels are attained. Transmit Noise Reduction (squelch) The transmit signal may be muted to eliminate transmission of excessive background noise. In this mode the signal level in the transmit path is compared with the high level threshold stored at address 1Dh. When the transmit signal level exceeds this threshold no loss is inserted into the transmit path. After exceeding the high level threshold the transmit signal level is then compared to a low level threshold stored at address 1Eh. When the transmit signal level falls below this threshold the transmit digital gain is reduced by the programmed amount (Pad0-2) and comparison reverts back to the high threshold level. The receive path gain is not altered by transmit noise reduction. Receive Noise Reduction (squelch) The receive signal may be muted to eliminate background noise resulting from a poor trunk connection. In this mode the signal level in the receive path is compared with the high level threshold stored at address 1Dh. When the receive signal level exceeds this threshold no loss is inserted into the receive path. After exceeding the high level threshold the receive signal level is then compared to a low level threshold stored at address 1Eh. When the receive signal level falls below this threshold the receive digital gain is reduced by the programmed amount (Pad2-0) and comparison reverts back to the high threshold level. The transmit path gain is not altered by receive noise reduction. Tx/Rx Switched Loss In this mode the programmed switched loss is inserted into either the transmit or receive path dependent only upon activity in the receive path. If receive path activity is above the programmed high level threshold then the switched loss is inserted into the transmit path. If receive path activity is below the programmed low level threshold then the switched loss is inserted into the receive path. MT9196 Preliminary Information This mode can be used to implement a loudspeaking function where the receive audio is routed to the SPKR± pins and transmit audio is sourced from the MIC+ pin. In this mode there is no algorithmic cancellation of echo so it is recommended that this switched loss program be used only in 4-wire systems (i.e., digital set to digital set). ➧ Auxiliary port path gains are: AUXin to Dout Din to AUXout AUXin to AUXout AUXin to HSPKR± AUXin to SPKR± Transducer Interfaces Four standard telephony transducer interfaces plus an auxiliary I/O are provided by the IDPC. These are: 11 dB 20.3 dB -12 dB -7.0 dB -1.1 dB 1.4 dB 5.0 dB TxINC=0 TxINC=1 RxINC=0 RxINC=1 Refer to the application diagrams of Figures 10 and 11 for typical connections to this analog I/O section. HSPKR + ➧ The handset microphone inputs (transmitter), pins M+/M- and the answerback microphone input MIC+. The nominal transmit path gain may be adjusted to either 6.0dB or 15.3dB. Control of this gain is provided by the TxINC control bit (Control register 2, address 0Fh). This gain adjustment is in addition to the programmable gain provided by the transmit filter and Digital Gain circuit. 75 Ω 150 ohm load (speaker) IDPC 75 Ω ➧ The handset speaker outputs (receiver), pins HSPKR+/HSPKR-. This internally compensated, fully differential output driver is capable of driving the load shown in Figure 4. The nominal handset receive path gain may be adjusted to either -12.1 dB or -9.6 dB. Control of this gain is provided by the RxINC control bit (Control register 2, address 0Fh). This gain adjustment is in addition to the programmable gain provided by the receive filter and Digital Gain circuit. ➧ The loudspeaker outputs, pins SPKR+/SPKR-. This internally compensated, fully differential output driver is capable of directly driving 6.5v p-p into a 40 ohm load. ➧ The Auxiliary Port provides an analog I/O, pins AUXin and AUXout, for connection of external equipment to the CODEC path as well as allowing access to the speaker driver circuits. ➧ AUXin is a single ended high impedance input (>10 Kohm). This is a self-biased input with a maximum input range of 2.5vp-p. Signals should be capacitorcoupled to this input. ➧ AUXout is a buffered output capable of driving 40 Kohms//150 pF. Signals for this output are derived from the receive path or from the AUXin and transmit microphones. HSPKR - Figure 4 - Handset Speaker Driver Microport The serial microport, compatible with Intel MCS-51 (mode 0), Motorola SPI (CPOL=0,CPHA=0) and National Semiconductor Microwire specifications provides access to all IDPC internal read and write registers. This microport consists of a transmit/ receive data pin (DATA1), a receive data pin (DATA2), a chip select pin (CS) and a synchronous data clock pin (SCLK). The microport dynamically senses the state of the serial clock each time chip select becomes active. The device then automatically adjusts its internal timing and pin configuration to conform to Intel or Motorola/National requirements. If SCLK is high during chip select activation then Intel mode 0 timing is assumed. The DATA1 pin is defined as a bidirectional (transmit/receive) serial port and DATA2 is internally disconnected. If SCLK is low during chip select activation then Motorola/National timing is assumed. Motorola processor mode CPOL=0, CPHA=0 must be used. DATA1 is defined as the data transmit pin while DATA2 becomes the data receive pin. Although the dual port Motorola controller configuration usually supports full-duplex communication, only half-duplex communication is possible in IDPC. The micro must discard non-valid data which it clocks in during a valid write transfer to 7-135 MT9196 Preliminary Information IDPC. During a valid read transfer from IDPC data simultaneously clocked out by the micro is ignored by IDPC. All data transfers through the microport are two-byte transfers requiring the transmission of a Command/ Address byte followed by the data byte written or read from the addressed register. CS must remain asserted for the duration of this two-byte transfer. As COMMAND/ADDRESS ➄ ➀ shown in Figures 5 and 6 the falling edge of CS indicates to the IDPC that a microport transfer is about to begin. The first 8 clock cycles of SCLK after the falling edge of CS are always used to receive the Command/Address byte from the microcontroller. The Command/Address byte contains information detailing whether the second byte transfer will be a read or a write operation and at what address. The next 8 clock cycles are used to transfer the data byte DATA INPUT/OUTPUT ➃ COMMAND/ADDRESS: ➀ DATA 1 RECEIVE D0 D1 D2 D3 D4 D5 D6 D7 D0 D1 D2 D3 D4 D5 D6 D7 D0 D1 D2 D3 D4 D5 D6 D7 DATA 1 TRANSMIT D0 D1 D2 D3 D4 D5 D6 D7 D0 D1 D2 D3 D4 D5 D6 D7 SCLK ② ➃ CS ➂ ➀ ➂ Delays due to internal processor timing which are transparent to IDPC. ② The IDPC:- latches received data on the rising edge of SCLK. - outputs transmit data on the falling edge of SCLK. ➂ The falling edge of CS indicates that a COMMAND/ADDRESS byte will be transmitted from the microprocessor. The subsequent byte is always data until terminated via CS returning high. ➃ A new COMMAND/ADDRESS byte may be loaded only by CS cycling high then low again. D7 ➄ The COMMAND/ADDRESS byte contains: 1 bit - Read/Write 5 bits - Addressing Data 2 bits - Unused X X A4 A3 A2 A1 D0 A0 R/W Figure 5 - Serial Port Relative Timing for Intel Mode 0 COMMAND/ADDRESS ➄ ➀ DATA INPUT/OUTPUT ➃ COMMAND/ADDRESS: ➀ DATA 2 RECEIVE D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 DATA 1 TRANSMIT D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 SCLK ② ➃ CS ➂ ➂ ➀ Delays due to internal processor timing which are transparent to IDPC. ② The IDPC:- latches received data on the rising edge of SCLK. - outputs transmit data on the falling edge of SCLK. ➂ The falling edge of CS indicates that a COMMAND/ADDRESS byte will be transmitted from the microprocessor. The subsequent byte is always data until terminated via CS returning high. ➃ A new COMMAND/ADDRESS byte may be loaded only by CS cycling high then low again. D7 ➄ The COMMAND/ADDRESS byte contains: 1 bit - Read/Write 5 bits - Addressing Data 2 bits - Unused R/W X A4 A3 A2 A1 D0 A0 Figure 6 - Serial Port Relative Timing for Motorola Mode 00/National Microwire 7-136 X MT9196 Preliminary Information 125 µs F0i DSTi, DSTo CHANNEL 0 D-channel CHANNEL 1 C-channel LSB first for DChannel CHANNEL 2 B1-channel CHANNEL 3 B2-channel CHANNELS 4-31 Not Used MSB first for C, B1- & B2Channels Figure 7 - ST-BUS Channel Assignment between the IDPC and the microcontroller. At the end of the two-byte transfer CS is brought high again to terminate the session. The rising edge of CS will tri-state the output driver of DATA1 which will remain tri-stated as long as CS is high. Intel processors utilize least significant bit first transmission while Motorola/National processors employ most significant bit first transmission. The IDPC microport automatically accommodates these two schemes for normal data bytes. However, to ensure timely decoding of the R/W and address information, the Command/Address byte is defined differently for Intel operation than it is for Motorola/ National operation. Refer to the relative timing diagrams of Figures 5 and 6. Receive data is sampled on the rising edge of SCLK while transmit data is made available concurrent with the falling edge of SCLK. Detailed microport timing is shown in Figure 15. Flexible Digital Interface A serial link is required to transport data between the IDPC and an external digital transmission device. IDPC utilizes the ST-BUS architecture defined by Mitel Semiconductor but also supports a strobed data interface found on many standard CODEC devices. This interface is commonly referred to as Synchronous Serial Interface (SSI). The combination of ST-BUS and SSI provides a Flexible Digital Interface (FDI) capable of supporting all Mitel basic rate transmission devices as well as many other 2B + D transceivers. The required mode of operation is selected via the ST-BUS/SSI control bit (FDI Control Register, address 10h). Pin definitions alter dependent upon the operational mode selected, as described in the following subsections as well as in the Pin Description tables. Quiet Code The FDI can be made to send quiet code to the decoder and receive filter path by setting the RxMUTE bit high. Likewise, the FDI will send quiet code in the transmit (DSTo) path when the TxMUTE bit is high. Both of these control bits reside in Control Register 1 at address 0Eh. When either of these bits are low their respective paths function normally. The -Zero entry of Table 1 is used for the quiet code definition. ST-BUS Mode The ST-BUS consists of output (DSTo) and input (DSTi) serial data streams, in FDI these are named Dout and Din respectively, a synchronous clock input signal CLOCKin (C4i), and a framing pulse input (F0i). These signals are direct connections to the corresponding pins of Mitel basic rate devices. Note that in ST-BUS mode the XSTL2 pin is not used. The CSL1 and CSL0 bits, as described in the SSI Mode section, are also ignored since the data rate is fixed for ST-BUS operation. However, the Asynch/Synch bit must be set to logic “0” for ST-BUS operation. The data streams operate at 2048 kb/s and are Time Division Multiplexed into 32 identical channels of 64 kb/s bandwidth. A frame pulse (a 244 nSec low going pulse) is used to parse the continuous serial data streams into the 32 channel TDM frames. Each frame has a 125 µSecond period translating into an 8 kHz frame rate. A valid frame begins when F0i is logic low coincident with a falling edge of C4i. Refer to Figure 12 for detailed ST-BUS timing. C4i has a frequency (4096 kHz) which is twice the data rate. This clock is used to sample the data at the 3/4 bitcell position on DSTi and to make data available on DSTo at the start of the bit-cell. C4i is also used to clock the IDPC internal functions (i.e., Filter/CODEC, Digital gain and tone generation) and to provide the channel timing requirements. The IDPC uses only the first four channels of the 32 channel frame. These channels are always defined, 7-137 MT9196 beginning with Channel 0 after the frame pulse, as shown in Figure 7 (ST-BUS channel assignments). The first two (D & C) Channels are enabled for use by the DEN and CEN bits respectively, (FDI Control Register, address 10h). ISDN basic rate service (2B+D) defines a 16kb/s signalling (D) Channel. IDPC supports transparent access to this signalling channel. ST-BUS basic rate transmission devices, which may not employ a microport, provide access to their internal control/status registers through the STBUS Control (C) Channel. IDPC supports microport access to this C-Channel. DEN - D-Channel In ST-BUS mode access to the D-Channel (transmit and receive) data is provided through an 8-bit read/ write register (address 15h) D-Channel data is accumulated in, or transmitted from this register at the rate of 2 bits/frame for 16 kb/s operation (1 bit/ frame for 8 kb/s operation). Since the ST-BUS is asynchronous, with respect to the microport, valid access to this register is controlled through the use of an interrupt (IRQ) output. D-Channel access is enabled via the (DEn) bit. DEn: When 1, ST-BUS D-channel data (1 or 2 bits/frame depending on the state of the D8 bit) is shifted into/ out of the D-channel (READ/WRITE) register. When 0, the receive D-channel data (READ) is still shifted into the proper register while the DSTo Dchannel timeslot and IRQ outputs are tri-stated (default). D8: When 1, D-Channel data is shifted at the rate of 1 bit/ frame (8 kb/s). When 0, D-Channel data is shifted at the rate of 2 bits/frame (16 kb/s default). 16 kb/s D-Channel operation is the default mode which allows the microprocessor access to a full byte of D-Channel information every fourth ST-BUS frame. By arbitrarily assigning ST-BUS frame n as the reference frame, during which the microprocessor D-Channel read and write operations are performed, then: (a) A microport read of address 15 hex will result in a byte of data being extracted which is composed of four di-bits (designated by roman numerals I,II,III,IV). 7-138 Preliminary Information These di-bits are composed of the two D-Channel bits received during each of frames n, n-1, n-2 and n3. Referring to Fig. 8a: di-bit I is mapped from frame n-3, di-bit II is mapped from frame n-2, di-bit III is mapped from frame n-1 and di-bit IV is mapped from frame n. The D-Channel read register is not preset to any particular value on power-up (PWRST) or software reset (RST). (b) A microport write to Address 15hex will result in a byte of data being loaded which is composed of four di-bits (designated by roman numerals I, II, III, IV). These di-bits are destined for the two D-Channel bits transmitted during each of frames n+1, n+2, n+3, n+4. Referring to Fig.8a: di-bit I is mapped to frame n+1, di-bit II is mapped to frame n+2, di bit III is mapped to frame n+3 and di bit IV is mapped to frame n+4. If no new data is written to address 15hex , the current D-channel register contents will be continuously re-transmitted. The D-Channel write register is preset to all ones on power-up (PWRST) or software reset (RST). An interrupt output is provided (IRQ) to synchronize microprocessor access to the D-Channel register during valid ST-BUS periods only. IRQ will occur every fourth (eighth in 8 kb/s mode) ST-BUS frame at the beginning of the third (second in 8 kb/s mode) ST-BUS bit cell period. The interrupt will be removed following a microprocessor Read or Write of Address 15 hex or upon encountering the following frames’s FP input, whichever occurs first. To ensure DChannel data integrity, microport read/write access to Address 15 hex must occur before the following frame pulse. See Figure 8b for timing. 8 kb/s operation expands the interrupt to every eight frames and processes data one-bit-per-frame. DChannel register data is mapped according to Figure 8c. CEn - C-Channel Channel 1 conveys the control/status information for the layer 1 transceiver. C-Channel data is transferred MSB first on the ST-BUS by IDPC. The full 64 kb/s bandwidth is available and is assigned according to which transceiver is being used. Consult the data sheet for the selected transceiver for its C-Channel bit definitions and order of bit transfer. When CEN is high, data written to the C-Channel register (address 14h) is transmitted, most MT9196 Preliminary Information IRQ Microport Read/Write Access FP n-3 n-2 n-1 n n+1 n+2 n+3 n+4* DSTo/ DSTi Di-bit Group Receive D0 D-Channel I II D1 D2 D3 No preset value D4 III IV D5 D6 D7 Di-bit Group Transmit D0 D-Channel I D1 D2 II D3 D4 III D5 D6 IV D7 Power-up reset to 1111 1111 * note that frame n+4 is equivalent to frame n of the next cycle. Figure 8a - D-Channel 16 kb/s Operation FP C4i C2 D0 Din tir =500 nsec max Rpullup= 10 k D1 tif =500 nsec max IRQ 8 kb/s operation 16 kb/s operation Reset coincident with Read/Write of Address 15 Hex or next FP, whichever occurs first Microport Read/Write Access Figure 8b - IRQ Timing Diagram FP Microport Read/Write Access IRQ n-7 n-6 n-5 n-4 n-3 n-2 n-1 n n+1 n+2 n+3 n+4 n+6 n+5 n+7 n+8 D-Channel Di-bit Group Receive D-Channel I D0 II D1 III D2 IV D3 No preset value V D4 VI D5 VII D6 VIII D7 Di-bit Group Transmit D-Channel I D0 II D1 III D2 IV D3 V D4 VI D5 VII D6 VIII D7 Power-up reset to 1111 1111 Figure 8c - D-Channel 8 kb/s Operation 7-139 MT9196 significant bit first, on DSTo. On power-up reset (PWRST) or software reset (RST, address 0Fh) all CChannel bits default to logic high. Receive CChannel data (DSTi) is always routed to the read register regardless of this control bit's logic state. When low, data transmission is halted and this timeslot is tri-stated on DSTo. B1-Channel and B2-Channel Channels 2 and 3 are the B1 and B2 channels, respectively. B-channel PCM associated with the Digital Gain, Filter/CODEC and transducer audio paths is selected on an independent basis for the transmit and receive paths. For example, the transmit path may use the B1 channel while the receive path uses the B2 channel. Although not normally required, this flexibility is allowed. For ST-BUS mode the configuration of bits 0 to 3, at address 12h, defines both the source of transmit audio and the B-Channel destination. The configuration of this register permits selection of only one transmit B-Channel at a time. If no valid transmit path has been selected, via the Transmit Path Selection Register, for a particular B-Channel then that timeslot output on DSTo is tri-stated. When a valid receive path has been selected, via the Receive Path Selection Register (address 13h), the active receive B-Channel is governed by the state of the B2/B1 control bit in Control register 1 (address 0Eh). Refer to the Path Selection section for detailed information. SSI Mode The SSI BUS consists of input and output serial data streams named Din and Dout respectively, a Clock input signal (CLOCKin), and a framing strobe input (STB). A 4.096 MHz master clock, at CLOCKin, is required for SSI operation if the bit clock is less than 512 kHz. The timing requirements for SSI are shown in Figures 13 and 14. In SSI mode the IDPC supports only B-Channel operation. The internal C and D Channel registers used in ST-BUS mode are not functional for SSI operation. The control bit B2/B1, as described in the ST-BUS section, is ignored since the B-Channel timeslot is defined by the input STB strobe. Hence, in SSI mode transmit and receive B-Channel data are always in the channel defined by the STB input. 7-140 Preliminary Information The data strobe input STB determines the 8-bit timeslot used by the device for both transmit and receive data. This is an active high signal with an 8 kHz repetition rate. SSI operation is separated into two categories based upon the serial data rate. If the bit clock is 512 kHz or greater then the bit clock is used directly by the internal IDPC functions allowing synchronous operation. In this case, the bit clock is connected directly to the CLOCKin pin while XSTAL2 is left unconnected. If the available bit clock rate is 128 kHz or 256 kHz then a 4096 kHz master clock is required to derive clocks for the internal IDPC functions. If this clock is available externally then it may be applied directly to the CLOCKin pin. If a 4096 kHz clock is not available then provision is made to connect a 4096 kHz crystal across the CLOCKin and XSTAL2 pins as shown in Figure 9. The oscillator circuit has been designed to require an external feedback resistor and load capacitors. This configuration allows normal ST-BUS operation and synchronous SSI operation with clocks which are not loaded by these extra components. CLOCKin 33 pF 100 kΩ XSTL2 33 pF 4096 kHz Nominal Figure 9 - External Crystal Circuit (for asynchronous operation) Applications where the bit clock rate is below 512 kHz are designated as asynchronous. The IDPC will generate and re-align its internal clocks to allow operation when the external master and bit clocks are asynchronous. In this case, the external bit clock is not connected to the IDPC. Control bits Asynch/Synch, CSL1 and CSL0 in FDI Control Register (address 10h) are used to program the bit rates as shown in Table 3. MT9196 Preliminary Information Asynch/ CSL1 CSL0 Synch Bit Clock Rate (kHz) CLOCKin (kHz) 1 0 0 128 4096 mandatory 1 0 1 256 4096 mandatory 0 0 0 512 512 0 0 1 1536 1536 0 1 0 2048 2048 0 1 1 4096 4096 Table 3 For synchronous operation data is sampled, from Din, on the falling edge of the bit clock during the time slot defined by the STB input. Data is made available, on Dout, on the rising edge of the bit clock during the time slot defined by the STB input. Dout is tri-stated at all times when STB is not true. If STB is valid but no transmit path has been selected (via the Transmit Path Control Register) then quiet code will be transmitted on Dout during the valid strobe period. There is no frame delay through the FDI circuit for synchronous operation. For asynchronous operation Dout and Din are as defined for synchronous operation except that data is transferred according to the itnernally generated bit clock. Due to resynchronization circuitry activity, the output jitter on Dout is nominally larger but will not affect operation since the bit cell period at 128 kb/s and 256 kb/s is relatively large. There is a one frame delay through the FDI circuit for asynchronous operation. Refer to the specifications of Figures 13 and 14 for both synchronous and asynchronous SSI timing. Path Selection Transmit and receive audio paths are independently programmed through their respective Path Control Registers at addresses 12h and 13h. Individual audio path circuit blocks are powered up only as they are required to satisfy the programmed values in the path control registers. More detail is provided in the Power-up/down Reset section. Transmit Transmit audio path configuration (Path Control Register, address 12h) is simply a matter of assigning one of the three analog signal inputs, or the digital tone generator, to the required transmit BChannel. Intermediate functions such as the transmit filter, encoder and transmit gain are automatically powered up and assigned as required. If transmit tones is selected then the digital tone generator must be programmed and enabled properly as described in the Digital Tone Generator section. Note that transmit tones may be enabled independently of the receive path. For ST-BUS mode the configuration of bits 0 to 3, at address 12h, defines both the source of transmit audio and the B-Channel destination. The configuration of this register permits selection of only one transmit B-Channel at a time. For SSI mode only the selections where bit 3 = 0 are allowed. This is because the B-Channel timeslot is defined by the input strobe at STB. If a selection where bit 3 = 1 is made it will be treated the same as the condition where B3 - B0 = all zero's. All reserved configurations should not be used. Receive The receive path assignment (Receive Path Control Register, address 13h) is different from the transmit path assignment. In this case a particular analog output port is assigned a source for its audio signal. The receive filter audio path and the Auxiliary In analog port are the available choices. This configuration allows flexibility in assignment. Two examples; the receive filter path can be assigned to the handset receiver, for a standard handset conversation, while permitting the loudspeaker to announce a message originating from the Auxiliary In port. Or perhaps the receive filter is assigned to both the loudspeaker and the Auxiliary Out port. This would allow a voice recorder or Facsimile machine, connected to the AUXout port to be monitored over the loudspeaker. The receive filter path itself has two possible signal sources, PCM from the Din port or synthesized tones, from the digital tone generator. In both cases receive digital gain is assigned automatically. The Receive Path Control Register combines all of these choices into simple output port assignments. In ST-BUS mode receive PCM from the Din port must be selected from either the B1 or the B2 channel. Control Bit B2/B1 in Control Register 1 (address 0Eh) is used to define the active receive BChannel. In SSI mode the active PCM channel is automatically defined by the STB input signal. 7-141 MT9196 Preliminary Information Sidetone ➧ The receive output drive transducers. All transducer output drivers are powered down forcing the output signals into tri-state. Output drivers (handset, handsfree-speaker, AUXout) are powered up/down individually as required by the state of the programmed bits in the Receive Path Control Register (address 13h) ➧ The transmit and receive filters and CODEC. All clocks for this circuit block are disabled. The complete section is automatically powered up as required by the programmed bits in the Transmit and Receive Path Control registers (addresses 12h and 13h). Whenever all path control selections are off this section is powered down. The CODEC and transmit/ receive filters cannot be powered up individually. ➧ The VRef and VBias circuits. Reference and Bias voltage drivers are tri-stated during power down causing the voltage at the pins to float. This circuit block is automatically powered up/ down as it is required by either the Filter/ CODEC or the transducer driver circuits. Whenever all path control selections are off this section is powered down. If the AUXin path to (any combination of the) output transducer drivers is selected then the VRef/VBias circuit is powered up but the Filter/CODEC circuit is not. ➧ The FDI and oscillator circuits. After PWRST, the device assumes SSI operation with Dout tristated while there is no strobe active on STB. If a valid strobe is supplied to STB, then Dout will be active, during the defined channel, supplying quiet code as defined in Table 1. If the device is switched to ST-BUS operation following PWRST, the entire Dout stream will be tri-stated until an active transmit channel is programmed. As well, following PWRST, the oscillator circuit is disabled and all timing for the IDPC functional blocks is halted. A clock signal applied to the MCL pin is prevented from entering further into the IDPC when the Asynch/ Synch bit is logic “1”. A voice sidetone path provides proportional transmit signal summing into the receive handset transducer driver. Details are provided in the Filter/CODEC section. Watchdog To maintain program integrity an on-chip watchdog timer is provided for connection to the microcontroller reset pin. The watchdog output WD goes high while the IDPC is held in reset via PWRST. Release of PWRST will cause WD to return low immediately and will also start the watchdog timer. The watchdog timer is clocked on the falling edge of STB/F0i and requires only this input, along with VDD, for operation. Note that in SSI mode, if STB disappears the watchdog will stop clocking. This will not harm processor operation but there is no longer any protection provided. If the watchdog reset word is written to the watchdog register (address 11h) after PWRST is released, but before the timeout period (T=512 mSec) expires, a reset of the timer results and WD will remain low. Thereafter, if the reset word is loaded correctly at intervals less than 'T' then WD will continue low. The first break from this routine, in which the watchdog register is not written to within the correct interval or it is written to with incorrect data, will result in a high going WD output after the current interval 'T' expires. WD will then toggle at this rate until the watchdog register is again written to correctly. 5-BIT WATCHDOG RESET WORD B7 B6 B5 B4 B3 B2 B1 B0 X X X 0 1 0 1 0 x=don’t care Power-up/down & PWRST/Software Reset While the IDPC is held in PWRST no device control or functionality is possible. While in software reset (RST=1, address 0Fh) only the microport and watchdog are functional. Software reset can only be removed by writing RST logic low or by the PWRST pin. After Power-up reset (PWRST) or software reset (RST) all control bits assume their default states; µ-Law functionality, usually 0 dB programmable gains and all sections of IDPC, except the microport and watchdog, into powered down states. This is the low power, stand-by condition. This includes: 7-142 To power up the FDI and oscillator circuits the PD bit of Control Register 1 (address 0Eh) must be cleared. To attain complete power-down from a normal operating condition, write all “0s” to the Transmit and Receive Path Control Registers (address 12h and 13h), set PD to logic 1 at address 0Eh, and Asynch/Synch to logic 1 at address 10h. MT9196 Preliminary Information IDPC Register Map 00 • • • 09 RESERVED 0A - RxFG2 RxFG1 RxFG0 - TxFG2 TxFG1 TxFG0 FCodec Control 1 0B Gain3 Gain2 Gain1 Gain0 - STG2 STG1 STG0 FCodec Control 2 0C ---------------------------------------RESERVED---------------------------------- 0D ---------------------------------------RESERVED---------------------------------- 0E PD Tfhp DialEn - - B2/B1 RxMute TxMute Control Register 1 0F RST - A/µ Smag/ CCITT RxINC TxINC - - Control Register 2 10 - ST-BUS/ SSI CEN DEN D8 Asynch/ Synch CSL1 CSL0 FDI Control 11 - - - W4 W3 W2 W1 W0 Watchdog 12 - - - - b3 b2 b1 b0 Tx Path Control 13 b7 b6 b5 b4 b3 b2 b1 b0 Rx Path Control 14 b7 b6 b5 b4 b3 b2 b1 b0 C-Channel Register 15 D7 D6 D5 D4 D3 D2 D1 D0 D-Channel Register 16 ---------------------------------------RESERVED---------------------------------- 17 - - Loop2 Loop1 - - - - Loopback Register 18 HiEN LoEn DTMF StEn Ring En - - - WR DTMF/Tone Ringer 19 TxG3 TxG2 TxG1 TxG0 RxG3 RxG2 RxG1 RxG0 Digital Gain 1A L7 L6 L5 L4 L3 L2 L1 L0 Low Tone Coeff 1B H7 H6 H5 H4 H3 H2 H1 H0 High Tone Coeff 1C Enable - MS1 MS0 - Pad2 Pad1 Pad0 Anti-Howl Control 1D - TH h6 THh5 TH h4 THh3 THh2 THh1 THh0 High Threshold 1E - TH l6 THl5 TH l4 THl3 THl2 THl1 THl0 Low Threshold 1F • • • 3F RESERVED 7-143 MT9196 Preliminary Information Register Summary ADDRESSES = 00h to 09h ARE RESERVED Filter Codec Control Register 1 - ADDRESS = 0Ah WRITE/READ VERIFY - TxFG2 TxFG1 TxFG0 3 2 1 0 RxFG2 RxFG1 RxFG0 7 6 Receive Gain Setting (dB) 5 4 RxFG2 RxFG 1 RxFG0 Transmit Gain Setting (dB) Power Reset Value X000 X000 TxFG 2 TxFG 1 TxFG 0 0 0 0 (default) 0 0 0 0 -1 0 0 1 1 0 0 1 -2 0 1 0 2 0 1 0 -3 0 1 1 3 0 1 1 -4 1 0 0 4 1 0 0 -5 1 0 1 5 1 0 1 -6 1 1 0 6 1 1 0 -7 1 1 1 7 1 1 1 (default) 0 RxFGn = Receive Filter Gain n TxFGn = Transmit Filter Gain n Filter Codec Control Register 2 Gain3 Gain2 7 Gain1 6 Speaker Gain (dB) Gain3 = 1 Gain3 = 0 16 12 8 4 0 -4 -8 -12 8 4 0 -4 -8 -12 -16 -20 ADDRESS = 0Bh WRITE/READ VERIFY Gain0 5 4 - STG2 STG1 STG0 3 2 1 0 Gain2 Gain1 Gain0 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 Side-tone Gain Setting (dB) (default) OFF -9.96 -6.64 -3.32 0 3.32 6.64 9.96 Power Reset Value 0010 X000 STG 2 STG 1 STG 0 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 STGn = Side-tone Gain n ADDRESS = 0Ch RESERVED Note: Bits marked "-" are reserved bits and should be written with logic "0". 7-144 MT9196 Preliminary Information ADDRESS = 0Dh RESERVED Control Register 1 PD Tfhp DialEN B2/B1 RxMUTE TxMUTE ADDRESS = 0Eh WRITE/READ VERIFY PD Tfhp 7 6 DialEN 5 - - 4 3 B2/B1 RxMute TxMute 2 1 A/µ Smag/CCITT RxINC TxINC 0 When high, the crystal oscillator and FDI blocks are powered down. When low, the oscillator and FDI circuits are active. When High, an additional highpass function (passband beginning at 400 Hz) is inserted into the transmit path. When low, this highpass filter is disabled. When high, a first order lowpass filter is inserted into the receive path (3dB = 1kHz). When low, this lowpass filter is disabled. When high, the receive Filter/CODEC operates on the B2-Channel. When low, the receive Filter/CODEC operates on the B1-Channel. This control bit has significance only for ST-BUS operation and is ignored for SSI operation. When high the received PCM stream is interrupted and replaced with quiet code; thus forcing the receive path into a mute state. When low the full receive path functions normally. When high the transmit PCM stream is interrupted and replaced with quiet code; thus forcing the output code into a mute state (only the output code is muted, the transmit microphone and transmit Filter/CODEC are still functional). When low the full transmit path functions normally. Control Register 2 RST Power Reset Value 100X X000 ADDRESS = 0Fh WRITE/READ VERIFY RST - A/µ Smag/ CCITT RxINC TxINC - - 7 6 5 4 3 2 1 0 Power Reset Value 0X00 00XX When high, a software reset occurs performing the same function as the hardware reset (PWRST) except that the microport and watchdog circuitry are not affected. A software reset can be removed only by writing this bit low or by a PWRST. When low, the reset condition is removed. When high, A-Law (de)coding is selected for the Filter/CODEC and DTMF generator circuits. When low, µ-Law (de)coding is selected for these circuits. When high, sign-magnitude code assignment is selected for the CODEC input/output. When low, CCITT code assignment is selected for the CODEC input/output; true sign, inverted magnitude (µ-Law) or true sign, alternate digit inversion (A-Law). When high, the receiver driver nominal gain is set at -9.6dB. When low, this driver nominal gain is set at -12.1dB. When high, the transmit amplifier nominal gain is set at 15.3dB. When low, this amplifier nominal gain is set at 6.0dB. Note: Bits marked "-" are reserved bits and should be written with logic "0". 7-145 MT9196 Preliminary Information FDI Control Register ADDRESS = 10h WRITE/READ VERIFY ST-BUS/ CEN SSI 7 6 ST-BUS/SSI CEN 5 DEN D8 Asynch/ Synch CSL1 CSL0 4 3 2 1 0 Power Reset Value X000 0000 When high, the FDI port operates in ST-BUS mode. When low, the FDI operates in SSI mode. When high, data written into the C-Channel register (address 14h) are transmitted during channel 1 on DSTo. When low, the channel 1 timeslot is tri-stated on DSTo. Channel 1 data received on DSTi is read via the CChannel register (address 14h) regardless of the state of CEN. This control bit has significance only for ST-BUS operation and is ignored for SSI operation. When high, data written into the D-Channel Register (address 15h) are transmitted during channel 0 on DSTo. When low, the channel 0 timeslot is tri-stated on DSTo. Channel 0 data received on DSTi is read via the DChannel register regardless of the state of DEN. This control bit has significance only for ST-BUS mode and is ignored for SSI operation. When high, the D-Channel operates at 8 kb/s. When low, the D-Channel operates at 16 kb/s default. Control bits Asynch/Synch, CSL1 and CSL0 are used to program the data clock (BCL) bit rates as shown in the following table (CSL1 and CSL0 are ignored in ST-BUS mode): DEN D8 Asynch/Synch, CSL1,CSL0 Asynch/Synch CSL1 CSL0 Bit Clock Rate (kHz) CLOCKin (kHz) 1 0 0 128 4096 mandatory 1 0 1 256 4096 mandatory 0 0 0 512 512 0 0 1 1536 1536 0 1 0 2048 2048 0 1 1 4096 4096 Note: Asynch/Synch must be set low for ST-BUS operation Watchdog Register ADDRESS = 11h WRITE - - - 0 1 0 1 0 7 6 5 4 3 2 1 0 Note: Bits marked "-" are reserved bits and should be written with logic "0". 7-146 Power Reset Value XXXX XXXX MT9196 Preliminary Information Transmit Path Control Register ADDRESS = 12h WRITE/READ VERIFY - - - - b3 b2 b1 b0 7 6 5 4 3 2 1 0 Power Reset Value XXXX 0000 Control bits b0 to b3 are used to configure the transmit path and select the transmit source. Note that for SSI mode all selections where b3 = 1 are not used and are interpreted as b0 - b3 = 0 (i.e., transmit path off). Source Programming Destination b3 b2 b1 b0 B1 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 B1 & B2 Off Handset mic (M + /M -) Handsfree mic (MIC +) AUXin Tx tones Reserved Reserved Reserved B2 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 Reserved Handset mic (M + /M -) Handsfree ic (MIC +) AUXin Tx Tones Reserved Reserved Reserved Receive Path Control Register ADDRESS = 13h WRITE/READ VERIFY b7 b6 b5 b4 b3 b2 b1 b0 7 6 5 4 3 2 1 0 Power Reset Value 0000 0000 Control bits b0 to b7 are used to assign a signal source individually to each receive path output. In addition transmit to receive voice sidetone path control is included. Destination Handset Speaker Handsfree Speaker Aux out Voice Sidetone Source Programming b1 0 0 1 1 b0 0 1 0 1 Off Rx Filter AUXin Reserved b3 0 0 1 1 b2 0 1 0 1 Off Rx Filter AUXin Reserved b6 b5 b4 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 b7 0 1 Off Rx Filter Reserved AUXin Handset mic (M+ /M -) Handsfree mic (MIC +) Reserved Reserved Voice sidetone path disabled Voice sidetone path enabled Note: Bits marked "-" are reserved bits and should be written with logic "0". 7-147 MT9196 Preliminary Information C-Channel Register ADDRESS = 14h WRITE/READ B7 B6 B5 B4 B3 B2 B1 B0 7 6 5 4 3 2 1 0 Power Reset Value 1111 1111 Micro-port access to the ST-BUS C-Channel information D-Channel Register ADDRESS = 15h WRITE/READ D7 D6 D5 D4 D3 D2 D1 D0 7 6 5 4 3 2 1 0 Power Reset Value 1111 1111 ADDRESS = 16h RESERVED Loopback Register Loop1 Loop2 Notes: ADDRESS = 17h WRITE/READ VERIFY - - Loop2 Loop1 - - - - 7 6 5 4 3 2 1 0 When high, the selected B-channel in ST-BUS mode (i.e., B2/B1 and Transmit and Receive Path selections) or the strobed B-channel in SSI mode is looped back from Din to Dout through the FDI block. The C & D channels (ST-BUS mode) are not looped back. When low, the device operates normally. When high, Loop1 is invoked with the transmit and receive digital gain adjustment being included. This loopback should only be used if PCM resides in the B-channel. If a data pattern is being looped back then use Loop1 or use Loop2 after ensuring that the transmit and receive digital gain registers are set to 0dB (address 19h). When low, the device operates normally. 1) do not enable Loop1 and Loop2 simultaneously. 2) both loopback modes add an extra frame delay to the data transmission. 3) ensure that all other bits of address 17h are written logic low when accessing this register. Note: Bits marked "-" are reserved bits and should be written with logic "0". 7-148 Power Reset Value XX00 XXXX MT9196 Preliminary Information DTMF/Tone Ringer Control Register LoEN DTMF St EN HiEN 7 6 ADDRESS = 18h WRITE/READ VERIFY Ring En 5 4 - - - WR 3 2 1 0 Power Reset Value 0000 XXX0 HiEN, LoEN When high, the programmed tone, for the respective high or low group, is generated. When low, tone generation is disabled for the respective low or high group. DTMF St EN When high, programmed DTMF is muxed into the receive path replacing the receive PCM signal. When low, the receive path functions normally. Ring EN When high, the tone ringer generator is enabled using the coefficients at addresses 1Ah and 1Bh as well as the WR control bit. For the ringer tone to be applied to the loudspeaker the proper path must be selected via the Receive Path Control Register (address 13h). When low, the ring generator circuit is disabled. When high, the tone ringer circuit will toggle between the two programmed frequencies at a 5 Hz rate. When low, the tone ringer warble rate is 10Hz. WR Digital Gain Register TxG3 7 ADDRESS = 19h WRITE/READ VERIFY TxG2 TxG1 6 5 TxG0 4 RxG3 RxG2 RxG1 RxG0 3 2 1 0 Power Reset Value 1000 1000 Transmit (TxG3-0) and receive (RxG3-0) control bits for programming gain in 3 dB increments. RxG3 RxG 2 RxG1 RxG 0 Gain Adjustment (dB) TxG3 TxG2 TxG1 TxG0 0 0 0 0 -24 0 0 0 0 0 0 0 1 -21 0 0 0 1 0 0 1 0 -18 0 0 1 0 0 0 1 1 -15 0 0 1 1 0 1 0 0 -12 0 1 0 0 0 1 0 1 -9 0 1 0 1 0 1 1 0 -6 0 1 1 0 0 1 1 1 -3 0 1 1 1 1 0 0 0 0 1 0 0 0 1 0 0 1 +3 1 0 0 1 1 0 1 0 +6 1 0 1 0 1 0 1 1 +9 1 0 1 1 1 1 0 0 +12 1 1 0 0 1 1 0 1 +15 1 1 0 1 1 1 1 0 +18 1 1 1 0 1 1 1 1 +21 1 1 1 1 Low Tone Coefficient Register ADDRESS = 1Ah WRITE/READ VERIFY L7 L6 L5 L4 L3 L2 L1 L0 7 6 5 4 3 2 1 0 Power Reset Value 0000 0000 The frequency of the low group tone is programmed by writing an 8-bit hexadecimal coefficient at this address according to the following equation: Frequency (in Hz) = 7.8125 x COEFF Where the hexadecimal COEFF is converted into a decimal integer between 0 and 255. Frequency resolution is 7.8125Hz in the range 0 to 1992 Hz. Note: Bits marked "-" are reserved bits and should be written with logic "0". 7-149 MT9196 Preliminary Information High Tone Coefficient Register ADDRESS = 1Bh WRITE/READ VERIFY H7 H6 H5 H4 H3 H2 H1 H0 7 6 5 4 3 2 1 0 Power Reset Value 0000 0000 The frequency of the high group tone is programmed by writing an 8-bit hexadecimal coefficient at this address according to the following equation: Frequency (in Hz) = 7.8125 x COEFF Where the hexadecimal COEFF is converted into a decimal integer between 0 and 255. Frequency resolution is 7.8125Hz in the range 0 to 1992 Hz. ADDRESS = 1Ch WRITE/READ VERIFY Anti-Howl Control Register Enable 7 Enable MS1, MS0 Pad2-0 - MS1 MS0 6 5 4 - Pad2 Pad1 Pad0 3 2 1 0 When high, the anti-howling circuit is enabled. When low, the anti-howling circuit is disabled. Encode the operational mode of the anti-howling circuit as follows. Details of each mode are found in the functional description of the anti-howling circuit. MS1 MS0 Operational Mode 0 0 Transmit Noise Squelch 0 1 Receive Noise Squelch 1 0 Anti-howling for group listening 1 1 Tx/Rx Switched Loss Three bits encoding the attenuation depth which will be switched into the transmit or receive paths by the anti-howling circuit. Note that 12 dB is the default value. Pad2 Pad1 Pad0 Attenuation (dB) 0 0 0 0 0 0 1 3 0 1 0 6 0 1 1 9 1 0 0 12 1 0 1 15 1 1 0 18 1 1 1 21 High Threshold Register THh6-0 ADDRESS = 1Dh WRITE/READ VERIFY - THh6 THh5 THh4 THh3 THh2 THh1 THh0 7 6 5 4 3 2 1 0 Power Reset Value X011 0000 Seven bits encoding the magnitude of the high threshold level. Encoding is in PCM sign-magnitude excluding the sign bit. THh0 - THh3 encode the step number while THh4 - THh6 encode the chord number. The default setting of 'X011 0000' encodes chord 3 step 0. The difference between the high and low thresholds defines the hysteresis for anti-howling. Low Threshold Register 7 THl6-0 Power Reset Value 0X10 X100 THI6 6 ADDRESS = 1Eh WRITE/READ VERIFY THI5 5 THI4 4 THI3 THI2 THI1 THI0 3 2 1 0 Power Reset Value X001 0100 Seven bits encoding the magnitude of the low threshold level. Encoding is in PCM sign-magnitude excluding the sign bit. THl0 - THl3 encode the step number while THl4 - THl6 encode the chord number. The default setting of 'X001 0100' encodes chord 1 step 4. The difference between the high and low thresholds defines the hysteresis for anti-howling. ADDRESSES 1Fh to 3Fh are RESERVED Note: Bits marked "-" are reserved bits and should be written with logic "0". 7-150 MT9196 Preliminary Information Applications 330 Ω +5V + + Typical External Gain for Handset AV= 5 - 10 100K 0.1 µF R Av = 1 + 2R T Typical External Gain for MIC AV= 20 - 25 R Electret + Microphone VBias T 100K - 10 µF 511 Ω 0.1 µF 511 Ω + + VBias 0.1 µF 330Ω VBias T R +5V 0.1 µF + 10µF 1K Electret + Microphone 0.1 µF 4 +5V INTEL MCS-51 or MOTOROLA SPI MicroController RESET 3 2 1 28 27 26 From Auxiliary Audio Source 5 25 6 24 7 23 CS 8 SCLK 9 21 DATA1 10 20 DATA2 11 19 IDPC 0.1µF To Auxiliary Audio Source 40Ω nom. 34Ω min. 22 75Ω 150Ω +5V 75Ω DATA2 Motorola Mode only 12 13 14 15 16 17 18 WD IRQ DC to DC CONVERTER DSTo +5V DSTi F0 Lin ZT C4 MT8972 DNIC Twisted Pair Lout 10.24 MHz Figure 10 - ST-BUS Application Circuit with MT8972 (DNIC) 7-151 MT9196 Preliminary Information 330 Ω +5V + + Typical External Gain for Handset AV= 5 - 10 100K 0.1 µF R Av = 1 + 2R T Typical External Gain for MIC AV= 20 - 25 Electret + Microphone VBias T R 100K - 10 µF 511 Ω 0.1 µF 511 Ω + + VBias 0.1 µF 330Ω VBias T R +5V 0.1 µF + 10µF 1K Electret + Microphone 0.1 µF 4 +5V INTEL MCS-51 or MOTOROLA SPI MicroController 3 2 1 From Auxiliary Audio Source 28 27 26 5 25 6 24 7 23 CS 8 SCLK 9 21 DATA1 10 20 11 DATA2 DATA2 Motorola Mode only 19 RESET WD 0.1µF To Auxiliary Audio Source 40Ω nom. 34Ω min. 22 IDPC 75Ω 150Ω +5V 75Ω 12 13 14 15 16 17 18 IRQ Twisted Pair Layer 1 Transceiver using SSI Synch Mode DOUT DOUT DIN DIN BCL BCL STB STB 4096 kHz Crystal Layer 1 Transceiver using SSI Asynch Mode Twisted Pair AA AAAA AAAA AAAA AA AAAAAAAA AAAAAAAA AA 4096 kHz AA AA AA AA AA AA AAAAAAAAAAAA AA AA AAAAAAAAAAAA AA AA AA AA AA 4096 kHz AA AA AAAA AA AAAAAAAA AA AAAAAAAA AAAAAA AAAA External Clock from Layer 1 Device or other source Figure 11 - SSI Application Circuit showing Synchronous or Asynchronous Operation 7-152 Preliminary Information MT9196 Programming Examples that these steps are from the power-up reset default definition. If some other state is currently true then some programming steps may be omitted while new ones may be required. Some examples of the programming steps required to set-up various telephony functions are given. Note Initialization Description Address DATA choose ST-BUS vs SSI (ie ST-BUS with C&D channels enabled) or (ie SSI at 256kHz BCL) 10h 10h 70h 05h power up oscillator and FDI same as above with B2 channel for ST-BUS 0Eh 0Eh 00h (other bits as required) 04h (other bits as required) A-Law vs µ-Law as required (ie CCITT µ-Law and gains low) or (ie CCITT A-Law and gains increased) 0Fh 0Fh 00h (default value so no write required) 2Ch Standard Full-duplex handset call Description Address DATA program Initialization steps above set sidetone gain (ie 0 dB) set gain (ie Rx = +3 dB, Tx = 0 dB) 0Bh 19h 04h (leave speaker gain defaulted to 0dB) 89h (or as required, defaults = 0dB) select transmit path (ie handset mic to B2 for ST-BUS) or (ie handset mic for SSI) 12h 12h 09h 01h 13h 13h 81h (for standard headset only) 91h 0Ah as required (0dB default) select receive path (ie handset speaker to Rx filter plus sidetone) or (as above plus receive to AUXout also) optional: set Filter/CODEC Rx and Tx gain Group Listening Description Address DATA program Initialization steps above set gain (ie Rx = +3 dB, Tx = 0 dB) 19h 89h (or as required, defaults = 0dB) set sidetone gain (ie 0 dB) and also set handsfree speaker gain independent of the rest of the receive path (ie 12dB) 0Bh 94h set high threshold level set low threshold level 1Dh 1Eh as required or leave default value as required or leave default value enable group listening with 12dB of atten. 1Ch A4h select transmit path (ie handset mic to B2 for ST-BUS) or (ie handset mic for SSI) 12h 12h 09h 01h 7-153 MT9196 select receive path (ie Rx filter to both handset and handsfree speakers with sidetone) Preliminary Information 13h Generate tone ringer Description Address Program Initialization steps above except A-Law vs µ-Law choices set speaker gain (ie -12dB) 0Bh write low tone coefficient 1Ah write high tone coefficient 1Bh select ringer as source for loudspeaker 13h start tone ringer (warble = 5Hz) 18h or (warble = 10Hz) 18h control ringer cadence by toggling 18h Ring EN (ie warble = 10Hz) Generate DTMF tones transmit only Description Program Initialization steps above set Tx digital gain (ie 0 dB) (-4dBm0/µ-Law,-10dBm0/A-Law) write low tone coefficient write high tone coefficient select transmit path (ie Tx tones to B2 for ST-BUS) or (ie Tx tones for SSI) start DTMF or for single tones DTMF sidetones only Description Program Initialization steps above set Rx digital gain (ie 0 dB) (-28dBm0) write low tone coefficient write high tone coefficient select receive path (ie Rx Filter to handset) or (ie Rx Filter to handsfree speaker) or (ie Rx Filter to AUX out) start DTMF program with sidetone or for single tones DTMF transmit and sidetone Description Program Initialization steps above set Tx digital gain (ie 0 dB) (-4dBm0/µ-Law,-10dBm0/A-Law) set Rx digital gain (ie 0 dB) (-28dBm0) write low tone coefficient write high tone coefficient select transmit path (ie Tx tones to B2 for ST-BUS) or (ie Tx tones for SSI) select receive path (ie Rx Filter to handset) or (ie Rx Filter to handsfree speaker) or (ie Rx Filter to AUX out) start DTMF program with sidetone or for single tones 7-154 Address 85h DATA are not required. 50h (or as required) as required as required 0Ch 11h 10h (default) 10h (on) 00h (off) 10h (on) 00h (off) etc... DATA 19h 80h (or as required) 1Ah 1Bh as required as required 12h 12h 18h 18h 0Ch 04h C0h (both Hi EN and Lo EN) 80h or 40h as required Address DATA 19h 1Ah 1Bh 08h (or as required) as required as required 13h 13h 13h 18h 18h 01h 04h 10h E0h (both Hi EN and Lo EN) A0h or 60h as required Address DATA 19h 88h (or as required) 1Ah 1Bh as required as required 12h 12h 0Ch 04h 13h 13h 13h 18h 18h 01h 04h 10h E0h (both Hi EN and LO EN) A0h or 60h as required MT9196 Preliminary Information Absolute Maximum Ratings Parameter Symbol Min Max Units VDD - VSS - 0.3 7 V VI/VO VSS - 0.3 VDD + 0.3 V ± 20 mA + 150 °C 750 mW 1 Supply Voltage 2 Voltage on any I/O pin 3 Current on any I/O pin (transducers excluded) II/IO 4 Storage Temperature TS 5 Power Dissipation (package) Plastic Recommended Operating Conditions Characteristics - 65 PD Voltages are with respect to VSS unless otherwise stated Sym Min Typ Max Units 5 5.25 V Test Conditions 1 Supply Voltage VDD 4.75 2 TTL Input Voltage (high)* VIHT 2.4 VDD V Includes Noise margin = 400 mV 3 TTL Input Voltage (low)* VILT VSS 0.4 V Includes Noise margin = 400 mV 4 CMOS Input Voltage (high) VIHC 4.5 VDD V 5 CMOS Input Voltage (low) VILC VSS 0.5 V 6 Operating Temperature TA - 40 + 85 °C * Excluding PWRST which is a Schmitt Trigger Input. Power Characteristics Characteristics 1 Supply Current (clock disabled, all functions off, PD=1) 2 Supply Current by function: Filter/Codec Digital Gain/Tone Handset Driver (bias only, no signal) Speaker Driver (bias only, no signal) Timing Control, C-channel, ST-BUS, etc. Total all functions enabled Sym Min Typ Max Units IDDC1 400 µA IDDF1 IDDF2 IDDF3 IDDF4 IDDF5 1.5 1.5 1.5 1.5 1.0 mA mA mA mA mA IDDFT 7.0 mA Test Conditions Outputs unloaded, Input signals static, not loaded See Note 1. See Note 1. See Notes 1 & 2. Note 1: Power delivered to the load is in addition to the bias current requirements. Note 2: IDDFT is not additive to IDDC1. 7-155 MT9196 Preliminary Information DC Electrical Characteristics† - Voltages are with respect to ground (VSS) Characteristics Sym Min 2.0 Typ‡ unless otherwise stated. Max Units Test Conditions V 1 Input HIGH Voltage TTL inputs VIHT 2 Input LOW Voltage TTL inputs VILT 3 Input HIGH Voltage CMOS inputs VIHC 4 Input LOW Voltage CMOS inputs VILC 5 VBias Voltage Output VBias VDD/2 6 Input Leakage Current IIZ 0.1 7 Positive Going Threshold Voltage (PWRST only) Negative Going Threshold Voltage (PWRST only) VT+ 8 Output HIGH Current IOH -5 - 16 mA VOH = 2.4V 9 Output LOW Current IOL 5 10 mA VOL = 0.4V 10 Output Reference Voltage VRef VDD/2-1.5 V No load 11 Output Leakage Current IOZ 0.01 µA VOUT = VDD and VSS 12 Output Capacitance Co 15 pF 13 Input Capacitance Ci 10 pF 0.8 3.5 V V 1.5 V V 10 3.7 µA Max. Load = 10kΩ VIN=VDD to VSS V 1.3 VT- 10 V † DC Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. CLOCKin Tolerance Characteristics Characteristics 1 CLOCKin (C4i) Frequency Min Typ‡ Max Units 4095.6 4096 4096.4 kHz Test Conditions † AC Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. Preferred Crystal Characteristics Nominal Frequency Frequency Tolerance Operating Temperature Shunt Capacitance Drive Level Series Resistance Load Capacitance Frequency Stability 7-156 4096 kHz ±100ppm @25°C -40°C to +85°C 7pF Maximum 5mW 130Ω maximum 20pF ±0.003%/°C from 25°C MT9196 Preliminary Information AC Characteristics† for A/D (Transmit) Path - 0dBm0 = 1.421Vrms for µ-Law and 1.477Vrms for A-Law, at the CODEC. (VRef=1.0 volts and VBias=2.5 volts.) Characteristics 1 Analog input equivalent to overload decision 2 Absolute half-channel gain Sym Min Typ‡ Max 5.79 6.0 ALi3.17 ALi3.14 Units Vp-p Vp-p Test Conditions µ-Law A-Law Both at CODEC M ± to PCM GAX1 GAX2 5.0 14.3 6.0 15.3 7.0 16.3 dB dB Transmit filter gain=0dB setting. Digital gain=0dB setting. TxINC = 0* TxINC = 1* MIC + to PCM GAX3 GAX4 9.5 18.8 11 20.3 12.5 21.8 dB dB TxINC = 0* TxINC = 1* AUXin to PCM GAX5 GAX6 9.5 18.8 11 20.3 12.5 21.8 dB dB TxINC = 0* TxINC = 1* @1020 Hz ±0.2 Tolerance at all other transmit filter settings (1 to 7dB) dB 3 Gain tracking vs. input level CCITT G.714 Method 2 GTX -0.3 -0.6 -1.6 4 Signal to total Distortion vs. input level. CCITT G.714 Method 2 DQX 35 29 24 5 Transmit Idle Channel Noise NCX NPX 6 Gain relative to gain at 1020Hz <50Hz 60Hz 200Hz 300 - 3000 Hz 3000 - 3400 Hz 4000 Hz >4600 Hz GRX 7 Absolute Delay DAX 360 µs at frequency of minimum delay 8 Group Delay relative to DAX DDX 750 380 130 750 µs µs µs µs 500-600 Hz 600 - 1000 Hz 1000 - 2600 Hz 2600 - 2800 Hz 9 Power Supply Rejection f=1020 Hz f=0.3 to 3 kHz f=3 to 4 kHz f=4 to 50 kHz 0.3 0.6 1.6 15 -71 -0.25 -0.9 PSSR PSSR1 PSSR2 PSSR3 37 40 35 40 dB dB dB 3 to -40 dBm0 -40 to -50 dBm0 -50 to -55 dBm0 dB dB dB 0 to -30 dBm0 -40 dBm0 -45 dBm0 16.5 -69 dBrnC0 dBm0p -25 -30 0.0 0.25 0.25 -12.5 -25 dB dB dB dB dB dB dB dB dB dB dB µ-Law A-Law ±100mV peak signal on VDD µ-law PSSR1-3 not production tested † AC Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing. * Note: TxINC, refer to Control Register 2, address 0Fh. 7-157 MT9196 Preliminary Information AC Characteristics† for D/A (Receive) Path - 0dBm0 = 1.421Vrms for µ-Law and 1.477Vrms for A-Law, at the CODEC. (VRef=1.0 volts and VBias=2.5 volts.) Characteristics Sym 1 Analog output at the CODEC full scale ALo3.17 ALo3.14 2 Absolute half-channel gain. Min Typ‡ Max 5.704 5.906 Units Vp-p Vp-p PCM to HSPKR± GAR1 GAR2 -13.1 -10.6 -12.1 -9.6 -11.1 -8.6 dB dB PCM to SPKR± GAR3 -1.0 0 1.0 dB PCM to AUXout GAR4 -14 -12 -10 dB Test Conditions µ-Law A-Law Receive filter gain = 0dB setting. Digital gain = 0dB setting. RxINC = 0* RxINC = 1* @1020 Hz Tolerance at all other receive filter settings (-1 to -7dB) ±0.2 dB 3 Gain tracking vs. input level CCITT G.714 Method 2 GTR -0.3 -0.6 -1.6 4 Signal to total distortion vs. input level. CCITT G.714 Method 2 GQR 35 29 24 5 Receive Idle Channel Noise NCR NPR 6 Gain relative to gain at 1020Hz 200Hz 300 - 3000 Hz 3000 - 3400 Hz 4000 Hz >4600 Hz GRR 7 Absolute Delay DAR 240 µs at frequency of min. delay 8 Group Delay relative to DAR DDR 750 380 130 750 µs µs µs µs 500-600 Hz 600 - 1000 Hz 1000 - 2600 Hz 2600 - 2800 Hz 9 Crosstalk CTRT CTTR dB dB G.714.16 D/A to A/D A/D to D/A 0.3 0.6 1.6 13 -78.5 -0.25 -0.90 dB dB dB 3 to -40 dBm0 -40 to -50 dBm0 -50 to -55 dBm0 dB dB dB 0 to -30 dBm0 -40 dBm0 -45 dBm0 15.5 -77 dBrnC0 dBm0p 0.25 0.25 0.25 -12.5 -25 dB dB dB dB dB -74 -80 µ-Law A-Law † AC Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. * Note: RxINC, refer to Control Register 2, address 0Fh. AC Electrical Characteristics† for Side-tone Path Characteristics 1 Absolute path gain Gain adjust = 0dB Sym Min Typ‡ Max Units Test Conditions GAS1 GAS2 -18.7 -16.2 -16.7 -14.2 -14.7 -12.2 dB dB TxINC, RxINC both 0* TxINC, RxINC both 1* M± inputs to HSPKR± outputs 1000 Hz † AC Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. * Note: RxINC and TxINC, refer to Control Register 2, address 0Fh. 7-158 MT9196 Preliminary Information AC Characteristics† for Auxiliary Analog LoopbackPath Sym Min Typ‡ Max Units AUXin to HSPKR± GAA1 GAA2 -3.1 -0.6 -1.1 1.4 0.9 3.4 dB dB AUXin to SPKR± GAA3 3.0 5.0 7.0 dB AUXin to AUXout GAA4 -9 -7 -5 dB Characteristics 1 Test Conditions Absolute gain for analog loopback from Auxiliary port. RxINC = 0* RxINC = 1* @1020 Hz † AC Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. * Note: RxINC, refer to Control Register 2, address 0Fh. AC Electrical Characteristics† for Ringer Tone Characteristics 1 Ringer Tone Output voltage (SPKR+ to SPKR-) Sym Typ‡ Units VR0 VR-4 VR-8 VR-12 VR-16 VR-20 VR-24 VR-28 6.0 3.79 2.39 1.51 951 600 379 239 Vp-p Vp-p Vp-p Vp-p mVp-p mVp-p mVp-p mVp-p Test Conditions Gain2 Gain1 Gain0 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1 Gain3 = 0 load>34 ohms across SPKR± † AC Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. Electrical Characteristics† for Analog Outputs Characteristics Sym Min Typ‡ 260 300 ohms 300 pF each pin: % 300 ohms load across HSPKR± (tol-15%), VO ≤ 693mVRMS, RxINC=1*, Rx gain=0dB 1 Earpiece load impedance EZL 2 Allowable Earpiece capacitive load ECL 3 Earpiece harmonic distortion ED 4 Speaker load impedance SZL 5 Allowable Speaker capacitive load SCL 6 Speaker harmonic distortion SD Max 0.5 34 Units Test Conditions across HSPKR± HSPKR+, HSPKR- 40 ohms 300 pF each pin % 40 ohms load across SPKR± (tol-15%), VO ≤ 6.2Vp-p, Rx gain=0dB 0.5 across SPKR± SPKR+, SPKR- † Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. * Note: RxINC, refer to Control Register 2, address 0Fh. 7-159 MT9196 Preliminary Information Electrical Characteristics† for Analog Inputs Characteristics 1 Sym Min Typ‡ Max Units Test Conditions Input voltage without overloading CODEC at MIC+ VIOLM 1.63 0.580 Vp-p Vp-p TxINC = 0, A/µ = 0* TxINC = 1, A/µ = 1* at AUXin VIOLA 1.63 0.580 Vp-p Vp-p TxINC = 1, A/µ = 0* TxINC = 1, A/µ = 1* across M+/M- VIOLH 2.90 1.03 Vp-p Vp-p TxINC = 0, A/µ = 0* TxINC = 1, A/µ = 1* Tx filter gain=0dB setting 2 Input impedance 50 10 ZI ZIA kΩ kΩ M+/M-, MIC+ AUXin to VSS † Electrical Characteristics are over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. * Note: TxINC and A/µ and refer to Control Register 2, address 0Fh. AC Electrical Characteristics† - ST-BUS Timing (See Figure 12) Characteristics Sym Min Typ‡ Max Units 1 C4i Clock Period tC4P 244 ns 2 C4i Clock High period tC4H 122 ns 3 C4i Clock Low period tC4L 122 ns 4 C4i Clock Transition Time tT 20 ns 5 F0i Frame Pulse Setup Time tF0iS 50 ns 6 F0i Frame Pulse Hold Time tF0iH 50 ns 7 DSTo Delay tDSToD 8 DSTi Setup Time tDSTiS 30 ns 9 DSTi Hold Time tDSTiH 30 ns 100 125 ns Test Conditions CL = 50pF, 1kΩ load.* † Timing is over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25 °C and are for design aid only: not guaranteed and not subject to production testing. * Note: All conditions → data-data, data-HiZ, HiZ-data. tT tC4P C4i tT 1 bit cell tC4H tC4L 70% AA 30% AA AA AA tDSToD DSTo 70% AA 30% AA AAA AA AA AAAA AAA tDSTiS DSTi 70% AA AAA AA 30%AAA AAAA AAA AA AAA AA AAAA AAA tT F0i tDSTiH 70% AA 30% AA tF0iS tF0iH tT NOTE: Figure 12 - ST-BUS Timing Diagram 7-160 Levels refer to %VDD AA AA MT9196 Preliminary Information AC Electrical Characteristics† - SSI BUS Synchronous Timing (see Figure 13) Characteristics Sym Min 1 BCL Clock Period tBCL 244 2 BCL Pulse Width High tBCLH 3 BCL Pulse Width Low Typ‡ Max Units Test Conditions 1953 ns BCL=4096 kHz to 512 kHz 122 ns BCL=4096 kHz tBCLL 122 ns BCL=4096 kHz 4 BCL Rise/Fall Time tR/tF 20 ns Note 1 5 Strobe Pulse Width tENW 8 x tBCL ns Note 1 6 Strobe setup time before BCL falling tSSS 80 tBCL-80 ns 7 Strobe hold time after BCL falling tSSH 80 tBCL-80 ns 8 Dout High Impedance to Active Low from Strobe rising tDOZL 90 ns CL=150 pF, RL=1K 9 Dout High Impedance to Active High from Strobe rising tDOZH 90 ns CL=150 pF, RL=1K 10 Dout Active Low to High Impedance from Strobe falling tDOLZ 90 ns CL=150 pF, RL=1K 11 Dout Active High to High Impedance from Strobe falling tDOHZ 90 ns CL=150 pF, RL=1K 12 Dout Delay (high and low) from BCL rising tDD 90 ns CL=150 pF 13 Din Setup time before BCL falling tDIS 50 ns 14 Din Hold Time from BCL falling tDIH 50 ns † Timing is over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing. NOTE 1: Not production tested, guaranteed by design. tBCL tBCLH tR CLOCKin (BCL) tF 70% 30% tBCLL tDIS Din tDIH 70% 30% tDD tDOZL Dout 70% 30% tDOZH tSSS STB tENW tSSH tDOLZ tDOHZ 70% 30% NOTE: Levels refer to % VDD (CMOS I/O) Figure 13 - SSI Synchronous Timing Diagram 7-161 MT9196 Preliminary Information AC Electrical Characteristics† - SSI BUS Asynchronous Timing (note 1) (see Figure 14) Characteristics Sym 1 Bit Cell Period Typ‡ Min TDATA 2 Frame Jitter Max 7812 3906 Units ns ns Test Conditions BCL=128 kHz BCL=256 kHz Tj 600 ns 3 Bit 1 Dout Delay from STB going high tdda1 Tj+600 ns C L=150 pF, RL=1K 4 Bit 2 Dout Delay from STB going high tdda2 600+ TDATA-Tj 600+ TDATA 600 + TDATA+Tj ns C L=150 pF, RL=1K 5 Bit n Dout Delay from STB going high tddan 600 + (n-1) x TDATA-Tj 600 + (n-1) x TDATA 600 + (n-1) x TDATA+Tj ns C L=150 pF, RL=1K n=3 to 8 TDATA1 TDATA-Tj TDATA+Tj ns 7 Din Bit n Data Setup time from STB rising tSU TDATA\2 +500ns-Tj +(n-1) x TDATA ns 8 Din Data Hold time from STB rising tho TDATA\2 +500ns+Tj +(n-1) x TDATA ns 6 Bit 1 Data Boundary n=1-8 † Timing is over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing. NOTE 1: Not production tested, guaranteed by design. Tj STB 70% 30% tdda2 tdha1 Dout tdda1 70% Bit 1 30% Bit 2 Bit 3 TDATA TDATA1 tho tsu Din 70% D2 D1 30% TDATA/2 TDATA D3 TDATA NOTE: Levels refer to % VDD (CMOS I/O) Figure 14 - SSI Asynchronous Timing Diagram 7-162 MT9196 Preliminary Information AC Electrical Characteristics† - Microport Timing (see Figure 15) Characteristics Sym Min Typ‡ Max Units 1 Input data setup tIDS 100 ns 2 Input data hold tIDH 30 ns 3 Output data delay tODD 4 Serial clock period tCYC 500 1000 ns 5 SCLK pulse width high tCH 250 500 ns 6 SCLK pulse width low tCL 250 500 ns 7 CS setup-Intel tCSSI 200 ns 8 CS setup-Motorola tCSSM 100 ns 9 CS hold tCSH 100 ns 10 CS to output high impedance tOHZ 100 Test Conditions ns 100 CL = 150pF, RL = 1K * ns CL = 150pF, RL = 1K † Timing is over recommended temperature range & recommended power supply voltages. ‡ Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing. * Note: All conditions → data-data, data-HiZ, HiZ-data. 2.0V DATA INPUT 0.8V tIDS DATA OUTPUT 0.8V tIDH Intel Mode = 0 tODD tCYC tCH AAAAAAAAAAAAAAAA 90% AAAA AAAAAAAA AAAAAAAA AAAAAAAA AAAA AAAA HiZAAAA AAAAAAAA AAAAAAAA AAAA AAAA AAAA AAAA AAAA AAAAAAAAAAAAAAAA AAAA 10% 2.0V 2.0V SCLK 0.8V tCSSI tOHZ tCL 2.0V CS 0.8V tCSSM tCSH tCH 2.0V SCLK 0.8V tCL tCYC Motorola Mode = 00 tODD AAAA AAAA AAAA AAAA A 90% AAAA AAAA AAAA AAAA A AAAA AAAA AAAA AAAA A AAAA AAAA AAAA AAAA A AAAA AAAA AAAA AAAA A HiZ AAAA AAAA AAAA AAAA A AAAA AAAA AAAA AAAA 10% AAAAAAAAAAAAAAAAA A tIDH DATA OUTPUT 2.0V 0.8V tIDS 2.0V DATA INPUT 0.8V NOTE: % refers to % VDD Figure 15 - Serial Microport Timing Diagram 7-163 MT9196 Notes: 7-164 Preliminary Information