ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR FEATURES * * * NW6006 DESCRIPTION The NW6006 device is a single-chip, 3/5 Volt CMOS caller ID with call waiting detection circuit. It can receive signals following Bellcore GR-30-CORE & SR-TSV-002476, BT SIN227 & SIN242, and ETSI ETS 300 788-1/-2 specifications. The NW6006 provides 1200 baud Bell 202 and ITU-T V.23 FSK demodulation, detection in stutter dial tone mode and CAS/DT-AS detection. Two seperate differential input amplifiers allow the device to be connected with both Tip/Ring and Telephone Hybrid receive pair. FSK demodulation is implemented only on Tip/Ring, while DT-AS(or CAS) detection can be on either Tip/Ring or Hybrid Receive. In addition, NW6006 provides a serial FSK data interface via which the data can be selected to be processed as a bit stream or extracted from a 1 byte built-in buffer. An on-chip Stutter Dial Tone Detector is provided to support the voice mail applications. The device can be used in feature or cordless phones with voice mail for BT Calling Line Identity Presentation (CLIP), CCA CLIP and Bellcore Calling Identity Delivery (CID) systems. It can also be used in caller ID boxes, modem, fax machines, answering machines, database query systems and Computer Telephony Integration (CTI) systems. * * * * * * * * * 1200 baud Bell 202 and ITU-T V.23 Frequency Shift Keying (FSK) Demodulation Stutter dial tone detection Compliant with following specifications: Bellcore GR-30-CORE & SR-TSV-002476 TIA/EIA-716, TIA/EIA-777 Draft TIA/EIA PN-4195 Draft British Telecom (BT) SIN227 & SIN242 ETSI ETS 300 778-1 and -2 Bellcore "CPE Alerting Signal (CAS)", British Telecom "Idle State and Loop State Tone Alert Signal" and ETSI "Dual Tone Alerting Signal (DT-AS)" detection Two seperate OP amps with adjustable gain for Tip/Ring and Telephone Hybrid connections Monitoring of the stop bit for framing error check Serial FSK data interface with selectable output of bit stream or 1 byte buffer FSK carrier detection 3 V or 5 V operation Low power CMOS with intelligent powerdown mode Operating temperature range: -40 C to +85 C Packages available: NW6006-XS 20 pin SOIC (where `X' is the revision ID) FUNCTIONAL BLOCK DIAGRAM OSCOUT OSCIN CB0 CB1 CB2 SDTEN Oscillator Bias Generator PWDN GS1EN SDTEN Control Bit Decoder FSKEN PWDN GS1EN CASEN GS2EN MODE VREF Stutter Dial Tone Detector IN1+ IN1GS1 IN2+ IN2GS2 Guard Time Tone Alert Detector CASEN + - ST/GT DR/STD EST CD/STRDT DCLK DATA Mux Mux + GS2EN FSK Demodulator FSKEN Data/Timing Recovery MODE Figure 1. Block Diagram The IDT logo is a registered trademark of Integrated Device Technology, Inc INDUSTRIAL TEMPERATURE RANGE (c)2002 Integrated Device Technology, Inc. JULY 2002 DSC-6049/3 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE PIN INFORMATION VREF IN1+ IN1GS1 GND OSCIN OSCOUT CB0 DCLK DATA 1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 IN2+ IN2GS2 CB2 CB1 VCC CD/STRDT ST/GT EST DR/STD Figure 2. Pin Assignment Name VREF IN1+ IN1GS1 GND OSCIN OSCOUT Type O I I O I O Pin No. 1 2 3 4 5 6 7 CB0 I 8 DCLK I/NC 9 DATA O 10 Description Reference Voltage. This output is used to bias the input OP amp. It is typically VCC/2. Non-inverting Input of the gain adjustable Tip/Ring OP amp. Inverting Input of the gain adjustable Tip/Ring OP amp. Gain Select Output of the gain adjustable Tip/Ring OP amp. The Tip/Ring signal can be attenuated or amplified at GS1 by adjusting the feedback resistor between GS1 and IN1-. The FSK signal is always detected by Tip/Ring OP amp while DT-AS(CAS) signal can be detected by either Tip/Ring or Hybrid OP amp. The OP amp selection is controlled by CB1 and CB2 bits. Ground. Oscillator Input. A 3.579545 MHz crystal or ceramic resonator should be connected between this pin and the OSCOUT. It can also be driven by an external clock source. Oscillator Output. A 3.579545 MHz crystal or ceramic resonator should be connected between this pin and the OSCIN. When an external clock drives OSCIN, this pin can be left floating. Control Bit 0 (FSK Data Interface Mode Select). This pin can select the 3-wire FSK data interface mode. A `0' on this pin indicates interface mode 0; while a `1' on this pin indicates interface mode 1. (The FSK data interface is consisted of DATA, DCLK and DR/STD pins.) When CB0 is high and CB1, CB2 are both low, the device is set into the power down state. Data Clock of the Serial FSK Interface. In mode 0 (CB0 is low), this pin is unused; In mode 1 (CB0 is high), this pin is an input which clock the FSK data byte out to the DATA pin. Data Output of the Serial FSK Interface. In mode 0 (CB0 is low), the FSK serial bit stream is output to the DATA pin directly. In mode 1 (CB0 is high), the start bit is stripped off, the data byte and the stop bit is stored in a 9-bit buffer. At the end of each word signaled by the DR/STD pin, the microcontroller should shift the byte out onto the DATA pin by applying 8 read pulses to the DCLK pin. A 9 th DCLK pulse will shift out the stop bit for framing error checking. 2 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE PIN INFORMATION (CONTINUED) Name Type Pin No. Description Data Ready or DT-AS Detection Delayed Steering Output. This pin is active low. When FSK demodulation is enabled, this pin is the Data Ready output. In FSK interface mode 0, this pin is unused and reads `1'. While in mode 1, this pin is normally high and goes low for half a bit time at the end of a word. If DCLK starts during DR low, the first rising edge of the DCLK input will return DR to high. In this way, reading of the first DATA bit can clear the interrupt requested by a low going DR. When DT-AS detection is enabled, this pin is the Delayed Steering Output. An active low signal on this output indicates the detection of a `guard time qualified' DT-AS. DT-AS Early Steering Output. This pin is an active high output to indicate the detection of a raw DT-AS signal. It is used with the ST/GT pin and external components to time qualify the detection. DT-AS Detection Steering Input/Guard Time Output. It's a CMOS output and an input of voltage comparator. It is used in conjunction with the EST pin and external components to time qualify a raw DT-AS signal detection. If the voltage at this pin is greater than the voltage threshold, DR/STD pin is asserted low to indicate that a DT-AS has been detected. A voltage less than the threshold enable the device to accept a new DT-AS and return the DR/ STD pin to high. FSK Carrier Detector or Stutter Dial Tone Detector Output. This is an active low CMOS output signal to indicate the presence of in-band FSK signal or valid Stutter Dial Tone signal. 3/5 V Power Supply. Control Bit 1 (Function Select 1). This pin is used with CB2 to select FSK demodulation, Tip/Ring DT-AS/Dial Tone detection, Hybrid DT-AS/Dial Tone detection with or without Stutter Dial Tone Detection. See Table 1. When CB0 is high, CB1 and CB2 pins are both low, the device is set into the power down state. Control Bit 2 (Function Select 0). This pin is used with CB2 to select FSK demodulation, Tip/Ring DT-AS/Dial Tone detection, Hybrid DT-AS/Dial Tone detection with or without Stutter Dial Tone Detection. See Table 1. When CB0 is high, CB1 and CB2 pins are both low, the device is set into the power down state. Gain Select Output of the gain adjustable Hybrid OP amp. The hybrid receive signal can be amplified or attenuated at GS2 by adjusting the feedback resistor between GS2 and IN2-. When the CPE is off-hook, DT-AS detection of the GS2 signal should be enabled via the CB1 and CB2 pins. Inverting Input of the gain adjustable Hybrid OP amp. Non-inverting Input of the gain adjustable Hybrid OP amp. DR/ STD O/NC 11 EST O 12 ST/GT I/O 13 CD/ STRDT VCC CB1 O I 14 15 16 CB2 I 17 GS2 IN2IN2+ O I I 18 19 20 Abbreviation Index CAS CDS CID CIDCW CLIP CNAM CND CNIC CO DT-AS MEI SDT TE ----------------------------------------------------------- CPE Alerting Signal ---------------------------------------------------------- Caller Display Service ---------------------------------------------------------- Calling Identity Delivery ---------------------------------------------------------- Calling Identity Delivery on Call Waiting ---------------------------------------------------------- Calling Line Identity Presentation --------------------------------------------------------- Calling Name Delivery --------------------------------------------------------- Calling Number Delivery ---------------------------------------------------------- Calling Number Identification Circuit ---------------------------------------------------------- Central Office ---------------------------------------------------------- Dual Tone Alert Signal ---------------------------------------------------------- Multiple Extension Interworking ---------------------------------------------------------- Stutter Dial Tone ---------------------------------------------------------- Terminal Equipment 3 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE PIN INFORMATION (CONTINUED) Table 1. Description of Control Bit Pins CB0-2 Pin CB0 Name FSK Data Interface Mode Select CB1 1 1 0 1 CB2 1 0 Description FSK Data Interface Mode 0: FSK bit stream is output directly. FSK Data Interface Mode 1: FSK byte is stored in a 1-byte buffer, which can be read serially by the microcontroller. FSK Demodulation is enabled. Tip/Ring input (GS1) is selected. In FSK Demodulation (CB0 = `1'), DR / STD is DR . Hybrid DT-AS Detection is enabled. Hybrid Receive input (GS2) is selected. DR/ STD is STD . When CB0 is high (`1'): Stutter Dial Tone Detection is enabled. CD/ STRDT is STRDT . When CB0 is low (`0'): Stutter Dial Tone Detection is disabled. CD/ STRDT is CD . Tip/Ring DT-AS Detection is enabled. Tip/Ring input (GS1) is selected. DR / STD is STD . When CB0 is high (`1'): Stutter Dial Tone Detection is enabled. CD/ STRDT is STRDT . When CB0 is low (`0'): Stutter Dial Tone Detection is disabled. CD/ STRDT is CD . Tip/Ring DT-AS detection is required for Bellcore MEI and BT on-hook CLIP. When CB0 is high (`1'): the NW6006 will be powered down. It draws minimal power supply current. When CB0 is low (`0'): for factory testing only. CB1 CB2 Function Select 1 Function Select 0 0 1 0 0 FUNCTIONAL DESCRIPTION CALLER ID SPECS SUPPORTED The NW6006 is a type II Caller ID device with Call Waiting capability. It supports Bellcore, BT and ETSI specifications. The major differences between above specs are as follows (see Fig. 11, Fig. 12 and Fig. 13 for reference): BELLCORE AND TIA Bellcore GR-30-CORE and SR-TSV-002476 define the requirement for the signalling services of Calling Number Delivery (CND), Calling Name Delivery (CNAM), VMWI (Visual Message Waiting Indicator) and Calling Identity Delivery on Call Waiting (CIDCW). In CND or CNAM service, information of the calling party is embedded in the silent interval between the first and second ringing. The NW6006 can detect and demodulate the incoming Bell-202 FSK data. In CIDCW service, information about an incoming caller is sent to the subscriber who is engaged in another call. A CPE Alerting Signal (CAS) indicates that a CIDCW data is incoming. The NW6006 can detect the alerting signal and demodulate the incoming FSK information which contains CIDCW data. The demodulated data is output onto the serial interface. In North America, Telecommunications Industry Association (TIA) 4 also defines standards. TIA specification TIA/EIA-716 defines Type I CPE requirements. A type II CPE specification document is drafted as TIA/EIA-777. BRITISH TELECOM BT SIN227 and SIN242 define the signal interface between the Central Office (CO) and the Terminal Equipment (TE) for the Caller Display Service (CDS). CDS provides CLIP (Calling Line Identity Presentation) that delivers to an idle state (on hook) TE the identity of an incoming caller before the first ring. A polarity reversal on the A and B wires indicates the arrival of a CDS call. After that comes an Idle State Tone Alert Signal, and then Caller ID FSK information transmitted in ITU-T V.23 format. When the subscriber is engaged in a call, the arrival of information about another incoming call is indicated by a Loop State Tone Alert Signal. The NW6006 can detect tone alert signal and demodulate the incoming ITU-T V.23 FSK signals. ETSI The ETSI caller identity specifications ETS 300 788-1 for on-hook and ETS 300 788-2 for off-hook define the requirements for CPE, while ETS 300 659-1 for on-hook and ETS 300 659-2 for off-hook define the end office requirements. The services such as CLIP and CLIP with Call Waiting in ETSI specifications are similar to those of Bellcore. The ETSI specifications are popularly used in Europe. NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE DT-AS DETECTION ON EITHER TIP/RING OR HYBRID RECEIVE PAIR In off-hook services, the detection of Dual Tone Alert Signal (DT-AS) will affect the quality of the call waiting service. Even though the end office has muted the far end party before and after it sends DT-AS, the near end user who is to receive the FSK information may be still talking. Therefore, the CPE must be able to detect DT-AS successfully in the presence of near end speech. Furthermore, imitation of DT-AS by speech will also affect the DT-AS detector, thus false detection may be generated. To achieve better DT-AS detection quality, a method is to put DT-AS detection on the telephone hybrid receive pair instead of on Tip/Ring. As the near end speech has been attenuated while the DT-AS level is the same as on Tip/Ring, the DT-AS immunity is improved. A CPE capability called Multiple Extension Interworking, in process of being defined by Bellcore, requests the CPE be capable of detecting DT-AS when the line is off-hook, although the CPE itself may be onhook. Under some conditions, an on-hook CPE may send an acknowledgment to the end office. Also, the on-hook CPE's capability of detecting DT-AS enables the call logs between on and off-hook CPEs to be maintained synchronous. In this way, when all off-hook CPEs are MEI compatible and DT-AS is received, one of the CPEs will send the acknowledgment signal and all CPEs will receive FSK. Therefore, if the DT-AS detector is connected only to the hybrid receive pair, the CPE can not detect DT-AS when it is on-hook. When the CPE is on-hook, either the hybrid is non-functional or the signal level is severely attenuated. Thus, an on-hook CPE must be able to detect DT-AS from Tip/Ring. The NW6006 provides two input OP amps via which the device can be connected both to Tip/Ring and to the Hybrid Receive pairs. Both connection can be differential or single-ended. FSK demodulation is implemented only on Tip/Ring, while DT-AS detection can be on either Tip/Ring or Hybrid Receive. Tip/Ring DT-AS detection is required for MEI and BT's on-hook CLIP. It should be noted here that as the Hybrid OP amp is for DT-AS detection only, its gain can always be adjusted specifically for the DTAS signal. BLOCK DESCRIPTION The NW6006 requires a 3.579545 MHz system clock and consists of four major functional blocks: Analog Input Circuit, Dual Tone Alert Signal Detection, Stutter Dial Tone Detection and FSK Demodulation. ANALOG INPUT CIRCUIT The input signal is processed by the Analog Input Circuit block, which is comprised of two OP amps and a bias source (VREF). VREF is the output of a low impedance voltage source used to bias the input OP amp, and is typically equal to VCC/2. The Tip/Ring OP amp (IN1+, IN1-, GS1 pins) is for connecting to Tip and Ring, while the Hybrid OP amp (IN2+, IN2-, GS2 pins) is for connecting to Hybrid Receive Pair. The gain adjustable OP amps are also used to select the input gain by connecting a feedback resistor between GS and the IN- pin. Fig. 3 shows the differential input configuration. In singleended configuration, the gain adjustable OP amp is connected as shown in Fig. 4. VREF NW6006 R3 R4 C1 R1 IN+ INR5 C2 R2 GS Differential Input Amplifier C1=C2 R1=R2 (For unity gain R5=R2) R3=(R4R5)/(R4+R5) Voltage Gain Av = R5/R2 Input Impedance Zin =2R1+ (1/C) Figure 3. Differential Input Gain Control Circuit C Rin IN+ IN- NW6006 Rf STUTTER DIAL TONE SPECS SUPPORTED The NW6006 also supports TIA/EIA Stutter Dial Tone specification PN-4159 Draft. This specification defines the requirement for the singalling of Stutter Dial Tone (SDT). When there is a message waiting in a customer's voicemail box, the serving telephone company's Central Office (CO) switch may apply a SDT signal to the customer's line when it is taken off-hook. An SDT CPE is used to automatically detect the SDT in response to an on-hook to off-hook transition and provide an indication. Voltage Gain Av = Rf / Rin GS VREF Figure 4. Single-ended Input Gain Control Circuit 5 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE DUAL TONE ALERT SIGNAL DETECTION The Dual Tone Alert Signal is used only in off-hook signalling in Bellcore system and ETSI system, but in BT system it is used in both on and off-hook signalling. The low and high tone frequencies of three different systems are as follows: Low Tone Frequency High Tone Frequency BT 2130 Hz 1.1% (on-hook) 2130 Hz 0.6% (off-hook) 2750 Hz 1.1% (on-hook) 2750 Hz 0.6% (off-hook) Bellcore & ETSI 2130 Hz 0.5% 2750 Hz 0.5% Fig. 5 shows the operation of the guard time circuit and Fig. 6 shows the waveform of the EST, ST/GT and STD pins. The total recognition time is tREC = tDP + tGP, where tDP is the tone present detection time and tGP is the tone present guard time. The total absent time is tABS = tDA + tGA, where tDA is the tone absent detection time and tGA is the tone absent guard time. The guard time is the RC time constant for the capacitor charge to VCC or discharge to GND. To get the unequal present and absent guard time, a diode can be connected as shown in Fig. 7 to provide different RC time constant (varying resistance value) during charging and discharging. When the device selects DT-AS detection, the bi-purpose output pin DR/STD is STD. STD goes low when DT-AS has been detected and return high after DT-AS has ended. The incoming Alert Signal goes through anti-alias filter and then is separated into high band and low band by two bandpass filters. The tone detection algorithm examines the filter outputs to validate the arrival of the DT-AS. The EST pin becomes active when both tones are detected. The EST is only the preliminary indication, it must be qualified by the "guard time" as required by Bellcore, BT and ETSI (a minimum duration for valid signals). STD is the guard time qualified DT-AS detection output, it indicates the correct detection. DT-AS t DP Alerting Signal tDA tGA EST ST/GT STD Q1 Switch Q2 Switch tGP tREC V TGT V TGT t ABS ON ON ON Figure 6. Guard Time Waveform NW6006 Dual tone detected P VCC Q1 VCC C3 VCC C Comparator VTGT ST/GT ST/GT R1 R2 R5 Q2 N tGP < tGA tGP=RPCIn((VCC-Vd(RP/R2))/ (VCC-VTGT -Vd(RP/R2))) tGA=R1CIn(VCC/VTGT ) RP=R1R2/(R1+R2) Vd=diode forward voltage NW6006 EST EST STD VCC C ST/GT R1 R2 tGP > tGA tGP=R1CIn(VCC/(VCC-VTGT )) tGA=RPCIn((VCC-Vd(RP/R2))/ (VTGT-Vd(RP/R2))) RP=R1R2/(R1+R2) Vd=diode forward voltage NW6006 Figure 5. Guard Time Circuit of Dual Tone Alert Signal Detection EST Figure 7. Guard Time Circuits with Unequal Present and Absent Times 6 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE FSK DEMODULATION The key part among the functions offered by NW6006 is FSK demodulation. This function is implemented by several stages: first, the carrier detector provides an indication of the presence of signal at the bandpass filter output; second, the device's dual mode serial interface allows convenient extraction of the 8-bit data words in the demodulated FSK bit stream. The FSK characteristics are different in BT, ETSI and Bellcore specifications. The signal frequencies in BT and ETSI correspond to ITU-T V.23; the Bellcore frequencies correspond to Bell 202. The NW6006 is compatible with both formats. It also meets the signal characteristics by setting the Tip/Ring input OP amp at unity gain in 5V operation. Mark Freq. (`1') Space Freq. (`0') ITU-T V.23 1300 Hz 1.5% 2100 Hz 1.5% Bell 202 1200 Hz 1% 2200 Hz 1% associated interrupt to be cleared by the first read pulse. Otherwise, DR stays low for half a nominal bit time (1/2400 sec) and then returns to high. After the last bit (Most Significant Bit) has been read, additional DCLKs are ignored. Fig. 18 shows the timing diagram of Mode `1' operation. Reading the stop bit is a method of checking framing errors. If it's certain that there is no framing error would occur, the microcontroller only needs to send 8 DCLK pulses to shift the data byte out. After the checksum byte has be received, all 9 bits should be read and framing error checked. STUTTER DIAL TONE DETECTION In some specifications, Stutter Dial Tone is used to indicate voice mails. The low and high tone frequencies of Stuttered Dial Tone signal are 350 Hz (tolerant range: 343 Hz to 357 Hz) and 440 Hz (tolerant range: 431 Hz to 449 Hz). When the device selects Stutter Dial Tone detection, the bipurpose output pin CD/STRDT is STRDT. STRDT goes low when dial tone signal has been detected and return high after dial tone signal has been ended (see Fig. 21). The incoming Stuttered Dial Tone signal goes through anti-alias filter and then is separated into high band and low band by two bandpass filters. The tone detection algorithm examines the filter outputs to validate the arrival of the Stutter Dial Tone signal. An embeded digital algorithm implements guard-time function. If the dial tone signal is qualified by the algorithm, the STRDT pin goes active to indicate a correct detection. For 3 V operation, the FSK receiver becomes easier to accept lower level signals than in 5 V operation. The Tip/Ring input OP amp gain should be reduced to maintain the FSK reject level. Serial FSK Interface The three wire DATA, DCLK and DR form the data interface of the FSK demodulation. The DATA pin is the serial data pin that outputs data to external devices. The DCLK pin is the data clock which is used in Mode `1' and is generated by an external device. The DR pin is the data ready signal used in Mode `1', also an output from the NW6006 to external devices. DR/STD pin is a dual purpose output pin, when FSK function is selected it is DR. Two modes are selectable via control of the device's CB0 pin: Mode `0' (CB0 is low), where the FSK bit stream is output directly; Mode `1' (CB0 is high), where the data byte and the stop bit are stored in a 9 bit buffer. Mode `0' (CB0 is low) In this mode, the device demodulates the incoming FSK signal, and output the data directly to the DATA pin. DCLK and DR pins are unused. Fig. 19 and Fig. 20 show the timing diagram of Mode `0' operation. Mode `1' (CB0 is high) In this mode, the received byte is stored on chip. The microcontroller supplies read pulses (DCLK) to shift the register contents serially out of the NW6006, onto the DATA pin. The NW6006 asserts DR to denote the word boundary and indicate to the microprocessor that a new word has become available. Internal to the device, the demodulated data bits are sampled and stored. Midway through the stop bit, the 8 data bits and the stop bit are parallel loaded into an 9-bit shift register and DR goes low. The contents of register are shifted out to DATA pin on DCLK's rising edge with LSB (Least Significant Bit) out first. If DCLK begins while DR is low, DR will return to high upon the first DCLK rising edge. This feature allows the 7 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE FSK CARRIER DETECTION The carrier detector detects the presence of a signal of sufficient amplitude at the output of the FSK bandpass filter. If the signal is qualified by a digital algorithm, it set the CD output to low indicating a successful carrier detection. NW6006 supplies a 10 ms hysteresis to allow for momentary signal drop out once CD has been activated. When there is no activity at the FSK bandpass filter output for 10 ms, CD is released. When CD is inactive (high), the raw output of the FSK demodulator is ignored by the FSK data output interface. In mode`0', the DATA pin is forced high. In mode `1', the internal shift register is not updated. If DCLK is clocked, DATA is undefined. Since signals such as DT-AS, DTMF tones and speech are within the FSK frequency band and thus may activate the carrier detector. The NW6006 should be put into DT-AS or power down mode when FSK is not expected to avoid false carrier detection and false demodulation. OTHER FUNCTIONS Power-down Mode The device provides the power-down feature to reduce the power consumption. Power-down can be activated by setting Control Bits 0-2 to `100'. Note that momentary transition of CB0-2 into the power-down code won't activate power-down but will reset the device. In this mode, both input OP amps, reference voltage and the oscillator are non functional. When the device is in power-down, DATA, DR/STD, CD/STRDT are high; EST and ST/GT are low. An intelligent Power-down feature is implemented to further reduce the operating current. When FSK is selected, DT-AS detector and Stuttered Dial Tone Detection are powered down. When DT-AS and STRDT are selected, FSK demodulator is powered down. The Tip/ Ring and Hybrid input OP amps are not affected in the intelligent Power-down. Crystal Oscillator A 3.579545 MHz crystal oscillator or other external clock source is required for NW6005. The crystal can be directly connected between OSCIN and OSCOUT pins without any external component. If an external clock source is used, OSCIN pin should be driven by the clock source and OSCOUT pin is left floating or is used to drive other devices. Fig. 8 shows some applications. (a) Connection of One Device with Crystal Oscillator NW6006 OSCIN OSCOUT 3.579545MHz (b) Common Crystal Connection of Several Devices Sharing One Timing Source NW6006 OSCIN OSCOUT NW6006 OSCIN NW6006 OSCOUT OSCOUT OSCIN 3.579545MHz to the next device Figure 8. Applicaiton of Clock Driven Circuit APPLICATION NOTE CONTROL BITS PROGRAMMING Functionality of the NW6006 can be selected by coding CB0-CB2, as shown in Table 2. Table 2. Control Bits Programming Functionality Group FSK Demodulation Mode 0 FSK Demodulation Mode 1 Hybrid DT-AS Detection with Stuttered Dial Tone Detection Hybrid DT-AS Detection Only Tip/Ring DT-AS Detection with Stuttered Dial Tone Detection Tip/Ring DT-AS Detection Only Power Down Factory Test Only CB0 0 1 1 0 1 0 1 0 CB1 1 1 1 1 0 0 0 0 CB2 1 1 0 0 1 1 0 0 HYBRID CONNECTION To optimize the device's talkdown and talkoff performance, Hybrid connection is recommended. There are two Op Amps in NW6006 which bring convenience for Hybrid connection. When connected to the Hybrid Op Amp, the Hybrid circuit will attenuate the speech signal at least 9 dB from the microphone to the speaker, which leads a much better performance of near-end talkdown and talkoff. It is highly recommended to demodulate the FSK signal using the Tip/Ring OP Amp and to detect the CAS signal using the Hybrid OP Amp. This implementation brings not only optimized talkdown and talkoff performance, but also the convenience to adjust FSK and CAS sensitivity separately. 8 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE GAIN SETTING Ideally, the gain of the two Op Amps would be set to 0 dB. But in real applications, the gain setting should be determined by industry standards as well as by customer requirements. The circuit and calculation method of gain setting is illustrated in Figs. 3 and 4. For Hybrid connection, the single-ended solution (Fig. 4) is often selected. Typically, the CAS sensitivity should be lower than the FSK sensitivity in order to prevent missing the FSK signal while the CAS signal is detected. Therefore, it is suggested to set the gain of the Op Amp for FSK demodulation 3 dB higher than that of the Op Amp for CAS detection. THE DIFFERENCE BETWEEN FSK MODE 0 AND MODE1 In FSK mode 0, the FSK serial bit stream is output to the DATA pin directly. DCLK and DR pins are unused. The microcontroller reads out the data by the serial data interface which is implemented by software programming. The flexibility of using software improves the immunity to interference. In FSK mode 1, the received byte is stored in an on-chip register. The microcontroller supplies read pulses (DCLK) to shift the register contents serially out of the NW6006, onto the DATA pin. The DR pin is also used to indicate the word boundary. VALID DT-AS EVALUATION DT-AS output will generate false detection if being interfered by speech. In this way, valid DT-AS pulse evaluation becomes necessary. The evaluation defines a minimum and maximum pulse duration, and maximum drop out time within that pulse duration. See Figure 22 for reference. 9 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE APPLICATION INFORMATION TIP TIP RING RING Telephone Hybrid Tx+ Tx- Microphone Speaker Rx+ Rx- 470k 56k 56k NW6006 VREF IN2+ IN2GS2 IN1+ 470k 2n2 470k 470k 2n2 VCC= 5V +/-10% 100n, 20% 100n 56k 330k CB2 CB1 VCC CD/STRDT ST/GT EST DR/STD C1 R1 A C2 R2 39k 470k IN1GS1 GND OSCIN OSCOUT CB0 DCLK DATA B 39k GND Xtal FSK Interface Mode 1 is selected Note: 1. Resistors are 1%, 0.1Watt; Unless stated, capacitors are 5%, 6.3 V. 2. All diodes in the circuit are 1N4148 or equivalent. 3. Xtal is 3.579545 MHz, 0.1% crystal or ceramic resonator. 4. Tip/Ring op amp gain = 0 dB; Hybrid Receive op amp gain = -3 dB. 5. For 1000 Vrms, 60 Hz isolation from Tip to Earth and Ring to Earth: R1, R2 = 430 k, 0.5 W, 5%, 500 V min. C1, C2 = 2n2, 250 V min. 6. For BT application, R3=R4= 422k; For Bellcore application, R3=825k, R4=226k. Figure 9. Typical Application Circuit For Bellcore MEI Compatible Type II Telephone with Stutter Dial Tone Detection, 5 V Operation 10 56k R3 R4 To Microcontroller From Microcontroller NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE Tx+ TIP TIP Microphone RING RING Telephone Hybrid Tx- Speaker Rx+ Rx- 282k 56k 56k NW6006 VREF IN2+ IN2GS2 IN1+ 282k 2n2 470k 470k 2n2 VCC= 3V +/-10% 100n, 20% 100n 56k 200k CB2 CB1 VCC CD/STRDT ST/GT EST DR/STD C1 R1 A C2 R2 39k 282k IN1GS1 GND B 39k GND Xtal OSCIN OSCOUT CB0 DCLK DATA FSK Interface Mode 1 is selected Note: 1. Resistors are 1%, 0.1Watt; Unless stated, capacitors are 5%, 6.3 V. 2. All diodes in the circuit are 1N4148 or equivalent. 3. Xtal is 3.579545 MHz, 0.1% crystal or ceramic resonator. 4. Tip/Ring op amp gain = 0 dB; Hybrid Receive op amp gain = -3 dB. 5. For 1000 Vrms, 60 Hz isolation from Tip to Earth and Ring to Earth: R1, R2 = 430 k, 0.5 W, 5%, 500 V min. C1, C2 = 2n2, 250 V min. 6. For BT application, R3=R4= 422k; For Bellcore application, R3=825k, R4=226k. Figure 10. Typical Application Circuit For Bellcore MEI Compatible Type II Telephone with Stutter Dial Tone Detection, 3 V Operation 11 56k R3 R4 To Microcontroller From Microcontroller NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE A/B Wires PWDN Note6 1st Ringing Alerting Signal Ch. Seizure Mark Message 2nd Ringing Note 1 A Note 2 B C D E F Note 2 Note 3 Note 4 FSKEN Note6 Note 5 CD DR Note 7 ... ... DCLK Note 7 DATA ..101010.. Data Figure 11. Bellcore On-hook Data Transmission Timing Diagram Notes: 1) A= 2 sec typ., B= 250 - 500 ms, C= 250 ms, D= 150ms, E depends on data length, Max C+D+E = 2.9 - 3.7 sec, F 200 ms. 2) In a battery operated CPE, NW6006 may be enabled only after the end of ringing to conserve power. 3) The microcontroller in the CPE powers down the NW6006 after CD goes inactive. 4) The microcontroller times out if CD is not activated on the 2nd ring and puts the device into Power-down mode. 5) FSK may be always enabled while the CPE is on-hook. To prevent the FSK demodulator from reacting to other inband signals such as speech, DT-AS or DTMT tones. The designer may choose to disable FSKduring the period that FSK signal is not expected. 6) PWDN and FSKEN are internal signals decoded from Control Bits CB2-0. 7) When CB0 is low, both DR and DCLK pins are unused. 12 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE CPE off-hook CPE mutes handset and disable keypad CPE sends ACK CPE unmutes handset and enable keypad A/B wires Note 2 CAS Mark Message A PWDN Note7 B C D Note 3 E F G Note 1 Note 5 FSKEN Note7 Note 4 Note 6 STD Hybrid DT-ASEN Note7 CD DR Note8 ... DCLK Note8 DATA Data Figure 12. Bellcore Off-hook Data Transmission Timing Diagram Notes: 1) A= 75 - 85 ms, B= 0 -100 ms, C= 55 - 65 ms, D= 0 - 500 ms, E= 58 - 75ms, F depends on data length, G 50 ms. 2) If AC power is not available, the designer may use the line power when the CPE goes off-hook and use battery power while on-hook. The CPE should also be CID (on-hook) capable . 3) If the end office fails to send the FSK signal, the CPE should disable FSKEN and unmute the handset and enable the keypad after this interval. 4) When FSK signal is not expected, the FSKEN should be set low to disable the FSK demodulator. 5) FSKEN should be high as soon as the CPE has finished sending the acknowledgement signal ACK. 6) FSKEN should be low when CD become inactive. 7) PWDN, FSKEN and Hybrid DT-ASEN are internal signals decoded from Control Bits CB2-0. 8) When CB0 is low, both DR and DCLK pins are unused. 13 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE Line Reversal A/B Wires Tip/Ring DT-ASEN Note 5 Alerting Signal Ch. Seizure Mark Message Ring A B C D E F G Note 1 PWDN Note 5 STD TE DC load TE AC load FSKEN Note 5 <120 A 20 5 ms 15 1 ms Current Wetting Pulse < 0.5 mA (optional) 50 - 150 ms Note 2 Zss Note 3 Note 4 CD DR Note 6 ... ... DCLK Note 6 DATA ..101010.. Data Figure 13. BT Idle State (on-hook) Data Transmission Timing Diagram Notes: 1) A 100ms, B=88 - 110 ms, C 45 ms (up to 5 sec), D= 80 -262 ms, E= 45 - 75 ms, F 2.5 sec (typ. 500 ms), G 200 ms. 2) By choosing tGA=15 ms, tABS will be 15-25 ms (refer to Fig. 8). Current wetting pulse and AC/DC load should be applied right after the STD rising edge. 3) AC and DC loads should be removed between 50-150 ms after the end of the FSK signal. The NW6006 may go to power down mode to save power. 4) FSKEN should be set low to disable the FSK demodulator, when the FSK signal is not expected. 5) Tip/Ring DT-ASEN, PWDN and FSKEN are internal signals decoded from Control Bits CB2-0. 6) When CB0 is low, both DR and DCLK pins are unused. 14 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE MAXIMUM RATING - Exceeding the following listed values may cause permanent damage. Power Supply Voltage: -0.3 V to 6 V Voltage on any pin other than supplies: GND - 0.3 V to VCC + 0.3 V Current at any pin other than supplies: 10 mA Storage Temperature: -65 C to +150 C RECOMMENDED OPERATING CONDITIONS Operating Temperature: -40 C to +85 C Power Supply Voltage: 3 V 10% or 5 V 10% Clock Frequency: 3.579545 MHz 0.1% Input Voltage: 0 V to VCC CRYSTAL SPECIFICATIONS Frequency: 3.579545 MHz Resonancy tolerance: 0.1%( -40C to +85C) Resonance mode: Parallel Load capacitance: 18 pF Maximum series resistance: 150 Maximum drive level: 2 mW DC ELECTRICAL CHARACTERISTICS Parameter ICCS ICC VT+ VTVHYS VIH VIL IOH CB0 CB1 CB2 DCLK, DATA, EST DR /STD , CD, ST/GT DCLK VCC Pin Description Power Supply Standby Current Operating Supply Current VCC = 5 V 10% VCC = 3 V 10% Schmitt Trigger Input High Threshold Schmitt Trigger Input Low Threshold Schmitt Hysteresis CMOS Input High Voltage CMOS Input Low Voltage Output High Sourcing Current 0.5VCC 0.3VCC 0.2 0.7VCC GND -0.8 VCC 0.3VCC Min Typ 0.5 Max 15 Units A Test Conditions Test 1 2.5 1.8 3.8 2.7 0.7VCC 0.5VCC mA mA V V V V V mA Test 2 VOH=0.9VCC Test 1: All inputs are VCC/GND except for oscillator pins. No analog input. Output unloaded. NW6006 in power down mode. Test 2: All inputs are VCC/GND except for oscillator pins. No analog input. Ouput unloaded. FSK is enabled. 15 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE DC ELECTRICAL CHARACTERISTICS (CONTINUED) Parameter IOL Iin1 Iin2 IOZ1 VREF RREF VTGT Pin DCLK, DATA DR/STD , CD EST, ST/GT IN1+, IN1IN2+, IN2DCLK CB0, CB1, CB2 ST/GT VREF ST/GT Description Output Low Sinking Current Input Current Input Current Output High Impedance Output Voltage Output Resistance Comparator Threshold Voltage 0.5VCC-0.1 0.5VCC-0.05 Min 2 1 10 5 0.5VCC+0.1 2 0.5VCC+0.05 Typ Max Units mA A A A V k V Vin = VCC to GND Vout = VCC to GND No Load Test Conditions VOL = 0.1VCC AC ELECTRICAL CHARACTERISTICS DUAL TONE ALERT SIGNAL DETECTION Parameter FL FH FDA FDR SIGAC SIGRJ TA SNR Description Low Tone Frequency High Tone Frequency Frequency Deviation Accept Frequency Deviation Reject Accept Signal Level per tone Reject Signal Level per tone (VCC = 5 V 10%, 3 V 10%) Positive and Negative Twist Accept # Signal to Noise Ratio ## Min Typ 2130 2750 Max Units Hz Hz Notes Nominal frequency Nominal frequency Within this range, tones are accepted. Outside this range, tones are rejected. Input op amp configured to 0 dB gain for 5 V operation, gain for 3 V operation is TBD. Signal level is per tone. 1.1% 3.5% -40 -2 -47 7 20 dBV dBV dB dB STUTTER DIAL TONE SIGNAL DETECTION Parameter FL FH FDA FDR SIGAC SIGRJ TA SNR Description Low Tone Frequency High Tone Frequency Frequency Deviation Accept High Tone Low Tone Frequency Deviation Reject High Tone Low Tone Accept Signal Level per tone Reject Signal Level per tone (VCC = 5 V 10%, 3 V 10%) Positive and Negative Twist Accept # Signal to Noise Ratio ## Min Typ 350 440 Max Units Hz Hz Hz Notes Nominal frequency Nominal frequency Within this range, tones are accepted. -7 -9 -13 -11 -31 7 9 13 11 -12 -36 Outside this range, tones are rejected. dBV dBV dB dB Input op amp configured to 0 dB gain for 5 V operation, gain for 3 V operation is TBD. Signal level is per tone. -6 20 6 # Twist = 20 |log ( fH amplitude / fL amplitude )|. ## Both tones have the same amplitude and at nominal frequencies. Band limited random noise 300-3400 Hz. Measurement valid only when tone is present. 16 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE AC ELECTRICAL CHARACTERISTICS (CONTINUED) GAIN ADJUSTABLE OP AMP Parameter IIN RIN VOS PSRR CMRR AVOL fC VO CL RL VCM Description Input Leakage Current Input Resistance Input Offset Voltage Power Supply Rejection Ratio Common Mode Rejection DC Open Loop Voltage Gain Unity Gain Bandwidth Output Voltage Swing Maximum Capacitive Load (GS) Maximum Resistive Load (GS) Common Mode Range Voltage Min 10 10 40 30 50 0.3 0.5 100 1.0 Typ Max 1 Units A M mV dB dB dB MHz V pF k Test Conditions GND VIN VCC 1kHz ripple on VCC VCMmin VIN VCMmax Load 100 k VCC -0.5 50 VCC-1.0 FSK DETECTION Parameter ID RS TR FMARK FSPACE FMARK FSPACE TA SNR Description Input Detection Level Reject Signal Level Transmission Rate Input Frequency Detection Bell 202 `1' (mark) Input Frequency Detection Bell 202 `0' (space) Input Frequency Detection ITU-T V.23 `1' (mark) Input Frequency Detection ITU-T V.23 0 (space) Positive and Negative Twist Accept Signal to Noise Ratio 1188 1188 2178 1280.5 2068.5 -10 20 1200 1200 2200 1300 2100 Min -40 Typ Max -6.5 -48 1212 1212 2222 1319.5 2131.5 10 Units dBV dBV baud Hz Hz Hz Hz dB dB Both mark and space have the same amplitude and at nominal frequencies. Band limited random noise: 200-3400 Hz. Present only when FSK signal is present. # Notes Production tested at VCC =3V 10%, or 5V 10%. Both mark and space have the same amplitude. # BT band is 200-3400 Hz, while Bellcore band is 0-4 kHz. Notes: dBV = decibels above or below a reference voltage of 1 Vrms. 17 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE AC TIMING CHARACTERISTICS POWER UP/DOWN AND FSK DETECTION Parameter t1 t2 t3 t4 t5 Description Power Up Time Power Down Time Input FSK to CD low delay Input FSK to CD high delay Hysteresis Min Typ Max 50 1 25 Units ms ms ms ms ms Test Conditions 10 10 DUAL TONE ALERT SIGNAL Parameter t6 t7 Description Alert Signal Present Detect Time Alert Signal Absent Detect Time Min 4 0.1 Typ Max 14 8 Units ms ms Test Conditions Power down is enabled by Control Bits OSCOUT t1 t2 Figure 14. Power Up/Down Timing Tip/Ring FSK Signal CD t3 t4 Figure 15. FSK Detection Time Tip/Ring or Hybrid Receive Pair Alert Signal EST t6 t7 Figure 16. Dual Tone Alert Signal Detection Time 18 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE AC TIMING CHARACTERISTICS (CONTINUED) SERIAL INTERFACE (MODE `1') Parameter t11 t12 t13 t14 t15 t16 t17 Description DCLK Cycle Time DCLK High Time DCLK Low Time DCLK Rise Time DCLK Fall Time DCLK Low Setup to DR DCLK Low Hold Time after DR Min 1 0.3 0.3 Typ Max Units s s s ns ns ns ns Test Conditions 100 100 500 500 t13 t12 DCLK t14 t11 t15 Figure 17. DCLK Timing in Mode `1' Internal Demodulated Bit Stream Nth byte (N+1)th byte stop start b7 b0 b1 b2 b3 b4 b5 b6 b7 stop start DR note 1 t16 t17 note 2 DCLK DATA b7 (N-1)th byte stop b0 b1 b2 b3 b4 b5 b6 b7 stop Nth byte b0 Figure 18. Serial Data Interface Timing in MODE `1' Notes: 1. DCLK clears DR. 2. DR not cleared by DCLK, low for a maximum time of 1/2 bit width. 19 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE AC TIMING CHARACTERISTICS (CONTINUED) SERIAL INTERFACE (MODE `0') Parameter DR t21 t22 t23 Description Data Rate Input FSK to DATA Delay DATA Rise Time DATA Fall Time Min 1188 Typ 1200 1 Max 1212 5 200 200 Units baud ms ns ns Test Conditions 1 2 2 Test conditions: 1. FSK input data at 1200 12 buad. 2. Load of 50 pF. DATA t22 t23 Figure 19. DATA Output Timing in Mode `0' start Nth byte stop start (N+1)th byte stop start TIP/RING b7 1 0 t21 b0 b1 b2 b3 b4 b5 b6 b7 Nth byte 1 0 b0 b1 b2 b3 b4 b5 b6 b7 (N+1)th byte 1 0 b0 b1 start start start DATA b7 b0 b1 b2 b3 b4 b5 b6 b7 stop b0 b1 b2 b3 b4 b5 b6 b7 stop b0 b1 b2 Figure 20. Serial Data Interface Timing in MODE `0' 20 NW6006 ENHANCED TYPE II CALLER ID DECODER WITH STUTTER DIAL TONE DETECTOR INDUSTRIAL TEMPERATURE RANGE STUTTER DIAL TONE SIGNAL Parameter t18 t19 t20 Description Stutter Dial Tone Signal Present Detect Time Stutter Dial Tone Signal Absent Detect Time Stutter Dial Tone Signal Duration Time Min 40 32 64 Typ 50 48 100 Max 68 52 108 Units ms ms ms SDT signal 100 ms on, 100 ms off. Test Conditions Tip/Ring or Hybrid Receive Pair Dial Tone Signal t20 STRDT t18 t19 Figure 21. Stutter Dial Tone Signal Detection Time Min. Pulse Duration Max. Min Maximum Dropout Span Figure 22. Valid DT-AS Pulses 21 PHYSICAL DIMENSIONS in Millimeters Symbol A A1 B C E e H h L D Dimension in MM Min Max 2.35 2.65 0.10 0.30 0.33 0.51 0.23 0.32 7.40 7.60 1.27 BSC 10.00 10.65 0.25 0.75 0.40 1.27 0 8 12.60 13.00 Dimension in Inch Min Max 0.093 0.104 0.004 0.012 0.013 0.020 0.009 0.013 0.291 0.299 0.050 BSC 0.394 0.419 0.010 0.029 0.016 0.050 0 8 - Figure 23. NW6006-XS 20 Pin SOIC Package Diagram CORPORATE HEADQUARTERS 2975 Stender Way Santa Clara, CA 95054 for SALES: 800-345-7015 or 408-727-6116 fax: 408-492-8674 www.idt.com for Tech Support: 408-330-1552 email: telecomhelp@idt.com 22