CMX673E3

CMX673 Call Progress Tone Detector D/673/5 June 2001 Provisional Issue Features Applications • Worldwide Tone Compatibility • Worldwide Payphone Systems • Single and Dual Tones Detected • Telephone Redialling Systems • Wide Dynamic Signal Range • Dialling Modems • Fast Response Time • Banking and Billing Systems • Low Power Operation 500µA at 3.0V • Telecom Test Equipment • 3.58MHz Xtal/Clock Oscillator • Telecom Security Systems 1.1 Brief Description The CMX673 is a general purpose call progress tone detector for use in Public Switched Telephone System (PSTN) applications. Call progress detection allows equipment which dials into the PSTN network to monitor the progress of the resulting call. Ringing, Busy, Not available and Answer states can be determined. The CMX673 uses advanced digital signal processing techniques to detect tones in the frequency band 315Hz to 650Hz. The use of DSP techniques allows the CMX673 to distinguish between valid call progress tone signals and line noise or voice, low false detection rates result. This is in contrast to other call progress detection devices which are based on simple filtering techniques. The detection timing of the CMX673 allows it to operate with almost any call progress system. In particular the ‘stuttered dial tone’ of voice mail messaging systems is supported. The use of digital processing and small geometry CMOS design techniques allows the CMX673 to offer a complete call progress detector which analyses both frequency and amplitude in a single 8 pin package. This, coupled with industry leading performance and substantially lower power supply requirements than comparable devices, demonstrates CML’s unique capability in this area. A single 3.58MHz crystal ensures accurate and repeatable performance. With supply requirements between 2.7V and 5.5V the CMX673 can be easily integrated into a wide range of telecom equipments. The CMX673 is pin to pin compatible with the M980 and TSC 75T980 and SSI980. It is available in DIP, TSSOP and SOIC packages. The CMX673 integrated circuit coupled with cadence measurement of the signals detected can identify virtually all call progress tones used worldwide.  2001 Consumer Microcircuits Limited CONTENTS Section Page 1.0 Features and Applications ............................................................. 1 1.1 Brief Description ................................................................................. 2 1.2 Block Diagram ...................................................................................... 3 1.3 Signal List .............................................................................................. 4 1.4 External Components ....................................................................... 5 1.5 General Description........................................................................... 6 1.5.1 1.5.1 1.5.2 1.5.3 1.5.4 1.6 Application Notes ............................................................................... 8 1.6.1 1.7 Overall Function Description..................................................... 6 Software Description .................................................................. 6 Glossary........................................................................................ 6 Block Diagram Description........................................................ 7 Decode Output Truth Table ....................................................... 7 General.......................................................................................... 8 Performance Specification ............................................................. 9 1.7.1 1.7.2 Electrical Performance ............................................................... 9 Packaging................................................................................... 12  2001 Consumer Microcircuits Limited 2 D/673/5 1.2 Block Diagram Figure 1 Block Diagram  2001 Consumer Microcircuits Limited 3 D/673/5 1.3 Signal List Package D4 E3 P1 Pin No. Pin No. Pin No. Name Type 2 3 1 XTAL/CLOCK I/P The input to the on-chip oscillator and external clock input. Components are on chip. 4 5 2 XTALN O/P The inverted output of the on-chip oscillator. 5 7 3 ENABLE I/P A logic ‘1’ applied to this input enables the DETECT output. A logic ‘0’ will reset DETECT output to a logic ‘0’. 7 8 4 DETECT O/P When a call progress signal is detected, this output goes to a logic ‘1’. 10 13 5 SIGIN I/P Signal input. Signals to this pin should be ac coupled. The dc bias of this pin is set internally. 12 15 6 VSS Power 14 17 7 VREF O/P 15 18 8 VDD Power 1, 3, 6, 8, 9, 11, 13, 16 1, 2, 4, 6, 9, 10, 11, 12, 14, 16, 19, 20 Notes: I/P = O/P = BI = Signal Description NC The negative supply rail (ground). Internally generated reference voltage, held at ½VDD. The positive supply rail. This pin should be decoupled to VSS by a capacitor. Internal Connection. Do not make any connection to these pins. Input Output Bidirectional  2001 Consumer Microcircuits Limited 4 D/673/5 1.4 External Components Typical Values: C1 C2 X1 0.1µF ± 20% 1µF ± 20% 3.579545MHz (refer to Section 1.7.1) Note: C1 is not required if the input is referenced to VREF. Figure 2 Recommended External Components  2001 Consumer Microcircuits Limited 5 D/673/5 1.5 General Description 1.5.1 Overall Function Description The CMX673 Call Progress Tone Detector uses different tone detection methods from those commonly found with other products. Many traditional devices from other suppliers use a bandpass filter followed by an energy detector. The filter is usually designed to pass input signals with a frequency between about 300Hz and 700Hz, and the amplitudes of signals in this range are then checked against a level threshold. Any signal of acceptable level in this frequency band is classed as a Call Progress tone, including signals due to speech and noise. False outputs caused by speech are a common feature with these products, and background noise may lead to a stuck “detect” output. The CMX673, by contrast, uses a stochastic signal processing technique based on analysis in both the frequency and time domains, with signal amplitude forming part of the decision process. This analysis includes checks on whether the signal has a “profile” which matches international standards for Call Progress tone, or a profile more likely to match that of speech, noise or no signal. The following Glossary, and the Decode Truth Table in Section 1.5.4 provide a simple explanation of the decoding functions and features offered by the CMX673. 1.5.2 Glossary Call Progress Tones: The single and dual frequency tones in the range 350Hz to 620Hz specified widely for call progress signalling. Call Progress Band: The nominal range 315Hz to 650Hz within which the CMX673 will detect Call Progress tones. The detection algorithm requires that the tones have the characteristics typical of Call Progress Tones. No Signal: The absence of an input signal or A signal below 250Hz or A signal between 750Hz and 10kHz. Note that signals above 10kHz should be at a level below -38dBm so as to avoid aliasing. Nominal: Subject to dynamic tolerances within the signal analysis process. Absolute values are not material or adverse to performance.  2001 Consumer Microcircuits Limited 6 D/673/5 1.5.3 Block Diagram Description Amplifier The input signal is amplified by a self-biased inverting amplifier. The dc bias of this input is internally set at ½VDD. Signal Analyser The frequency range, quality and consistency of the input signal is analysed by this functional block. To be classified as a call progress signal the input signal frequencies should lie between 315Hz and 650Hz. The signal to noise ratio must be 16dB or greater. The signal must be consistent over a period of about 80ms. These decode criteria are continuously monitored and the assessment is updated every 6ms; reference Figure 4. Control Logic This block categorises the nature of the signal into two decoded output states and controls the output pin. See the Decode Output Truth Table in Section 1.5.4. Level Detector The level detector operates by measuring the level of the amplified input signal and comparing it with a preset threshold. The level detector output goes to the Control and Output Logic block. The data output is gated with the level detector’s output. The data output is valid only if the level detector output is true. Xtal/Clock Oscillator If the on-chip Xtal oscillator is to be used, then external component X1 is required. If an external clock source is to be used, then it should be connected to the XTAL/CLOCK input pin and the XTALN pin should be left unconnected. 1.5.4 Decode Output Truth Table “DETECT” CONDITIONS 0 No Signal 1 Call Progress Band: Will detect 350+440, 400+450, 440+480 400, 425,440, 450, 480+620, 600 and 620Hz tones Note that DETECT responds to the whole range of call progress tones from 315Hz to 650Hz. Table 1 Decode Output Truth Table  2001 Consumer Microcircuits Limited 7 D/673/5 1.6 Application Notes 1.6.1 General On power-up, it will take 80ms to initialise the internal state, this delay should be accounted for before the DETECT output is valid. XTAL/CLOCK C2 1 8 X1 R5 XTALN 2 7 VREF R3 CMX673P1 ENABLE 3 R2 6 Cµ mor F/ oT _ DETECT 4 5 R1 C3 SIGIN Phone Line R4 + C4 Figure 3 A typical Telephone Line Circuit Application R1 R2 R3 R4 Note: 470kΩ 470kΩ 240kΩ 470kΩ R5 C3 C4 160kΩ 0.01µF 250V 0.01µF 250V 1. Resistors ±1%, Capacitors ±20% unless otherwise stated. 2. A low offset opamp is needed. An alternative set of component values can be used: R1 R2 R3 R4 Note: 499kΩ 499kΩ 54.9kΩ 499kΩ R5 C3 C4 49.9kΩ 0.001µF 300V 0.001µF 300V 3. Resistors ±1%, Capacitors ±2% unless otherwise stated. 4. A higher value of C3 and C4 will reduce the level sensitivity tolerance at around -38dBm.  2001 Consumer Microcircuits Limited 8 D/673/5 1.7 Performance Specification 1.7.1 Electrical Performance Absolute Maximum Ratings Exceeding these maximum ratings can result in damage to the device. Supply (VDD - VSS) Voltage on any pin to VSS Current into or out of VDD and VSS pins Current into or out of any other pin P1 Package Total Allowable Power Dissipation at Tamb = 25°C ... Derating Storage Temperature Operating Temperature Min. -0.3 -0.3 -30 -20 Max. 7.0 VDD + 0.3 +30 +20 Units V V mA mA Min. Max. 800 13.0 +125 +85 Units mW mW/°C °C °C Max. 300 5.0 +125 +85 Units mW mW/°C °C °C Max. 800 13.0 +125 +85 Units mW mW/°C °C °C Max. 5.5 3.59 Units V MHz -55 -40 E3 Package Total Allowable Power Dissipation at Tamb = 25°C ... Derating Storage Temperature Operating Temperature Min. -55 -40 D4 Package Total Allowable Power Dissipation at Tamb = 25°C ... Derating Storage Temperature Operating Temperature Min. -55 -40 Operating Limits Correct operation of the device outside these limits is not implied. Notes Supply (VDD - VSS) Xtal Frequency  2001 Consumer Microcircuits Limited 9 Min. 2.7 3.57 D/673/5 Operating Characteristics For the following conditions unless otherwise specified: Xtal Frequency = 3.579545MHz, S/N = 16dB, Noise Bandwidth = 5kHz, VDD = 3.0V to 5.0V, Tamb = -40°C to +85°C. 0dB = 775mVrms. Notes DC Parameters IDD (ENABLE = ‘1’) IDD (ENABLE = ‘1’) (VDD = 5.0V) (VDD = 3.0V) AC Parameters SIGIN pin Input Impedance Minimum Input Signal Level Input Signal Dynamic Range Signal to Noise Ratio Level Detector Must Detect Signal Level Must Not Detect Signal Level Call Progress Band Must Detect Range Must Not Detect Range Max. Units 1 1 1.0 0.5 1.5 1.0 mA mA 2 0.1 -38.0 MΩ dB dB 3 3 100 100 20.0 4 4 -38.0 ns ns dB -50.0 dB dB 650 250 Hz Hz 7 315 750 Logic Interface Input Logic “1” Level Input logic "0" level Input leakage current (Vin = 0 to VDD) Input Capacitance Output logic "1" level (lOH = 120µA) 5 5 5 5 6 Output logic "0" level (lOL = 360µA) 1. 2. 3. 4. 5. 6. 7. Typ. 40.0 16.0 Xtal/Clock Input ‘High’ Pulse Width ‘Low’ Pulse Width Gain (I/P = 1mVrms at 100Hz) Notes: Min. 6 80% 20% +5.0 -5.0 10.0 90% 10% VDD VDD µA pF VDD VDD Not including any current drawn from the detector pins by external circuitry. Small signal impedance over the frequency range 100Hz to 2000Hz and at VDD = 5.0V. Timing for an external input to the XTAL/CLOCK pin. Input signal level at VDD = 5.0V, scale signal for different VDD. ENABLE pin. DETECT pin. Nominal values which are subject to dynamic tolerances within the signal analysis process, as a result of using stochastic signal processing techniques.  2001 Consumer Microcircuits Limited 10 D/673/5 Electrical Performance (continued) Figure 4 µ C Parallel Interface Timings For the following conditions unless otherwise specified: Xtal Frequency = 3.579545MHz, VDD = 3.0V to 5.0V, Tamb = -40°C to +85°C, S/N = 20dB. Notes Min. Typ. Max. Units 40.0 ms Signal Timings (ref. Figures 3, 4 and 5) tl Burst Length Ignored tL Burst Length Detected tGI Call Progress Tone Gap Length Ignored 8 tGD Call Progress Tone Gap Length Detected 8 tRP Call Progress Tone Response Time 9 80.0 ms tDRP Call Progress Tone De-Response Time 9 80.0 ms Notes: 80.0 ms 20.0 40.0 ms ms 8. Only applies to bursts of the same frequency. 9. Measured with 350+440Hz tone pair.  2001 Consumer Microcircuits Limited 11 D/673/5 1.7.2 Packaging Figure 5 P1 Mechanical Outline: Order as part no. CMX673P1 Figure 6 E3 Mechanical Outline: Order as part no. CMX673E3  2001 Consumer Microcircuits Limited 12 D/673/5 Call Progress Tone Detector CMX673 Figure 7 D4 Mechanical Outline: Order as part no. CMX673D4 Handling precautions: This product includes input protection, however, precautions should be taken to prevent device damage from electro-static discharge. CML does not assume any responsibility for the use of any circuitry described. No IPR or circuit patent licences are implied. CML reserves the right at any time without notice to change the said circuitry and this product specification. CML has a policy of testing every product shipped using calibrated test equipment to ensure compliance with this product specification. Specific testing of all circuit parameters is not necessarily performed. Oval Park - LANGFORD MALDON - ESSEX CM9 6WG - ENGLAND Telephone: +44 (0)1621 875500 Telefax: +44 (0)1621 875600 e-mail: sales@cmlmicro.co.uk http://www.cmlmicro.co.uk CML Microcircuits COMMUNICATION SEMICONDUCTORS CML Product Data In the process of creating a more global image, the three standard product semiconductor companies of CML Microsystems Plc (Consumer Microcircuits Limited (UK), MX-COM, Inc (USA) and CML Microcircuits (Singapore) Pte Ltd) have undergone name changes and, whilst maintaining their separate new names (CML Microcircuits (UK) Ltd, CML Microcircuits (USA) Inc and CML Microcircuits (Singapore) Pte Ltd), now operate under the single title CML Microcircuits. These companies are all 100% owned operating companies of the CML Microsystems Plc Group and these changes are purely changes of name and do not change any underlying legal entities and hence will have no effect on any agreements or contacts currently in force. CML Microcircuits Product Prefix Codes Until the latter part of 1996, the differentiator between products manufactured and sold from MXCOM, Inc. and Consumer Microcircuits Limited were denoted by the prefixes MX and FX respectively. These products use the same silicon etc. and today still carry the same prefixes. In the latter part of 1996, both companies adopted the common prefix: CMX. This notification is relevant product information to which it is attached. Company contact information is as below: CML Microcircuits (UK)Ltd CML Microcircuits (USA) Inc. CML Microcircuits (Singapore)PteLtd COMMUNICATION SEMICONDUCTORS COMMUNICATION SEMICONDUCTORS COMMUNICATION SEMICONDUCTORS Oval Park, Langford, Maldon, Essex, CM9 6WG, England Tel: +44 (0)1621 875500 Fax: +44 (0)1621 875600 uk.sales@cmlmicro.com www.cmlmicro.com 4800 Bethania Station Road, Winston-Salem, NC 27105, USA Tel: +1 336 744 5050, 0800 638 5577 Fax: +1 336 744 5054 us.sales@cmlmicro.com www.cmlmicro.com No 2 Kallang Pudding Road, 09-05/ 06 Mactech Industrial Building, Singapore 349307 Tel: +65 7450426 Fax: +65 7452917 sg.sales@cmlmicro.com www.cmlmicro.com D/CML (D)/1 February 2002