MX633 Call Progress Tone Detector

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DATA BULLETIN MX633 Call Progress Tone Detector PRELIMINARY INFORMATION Features Worldwide Tone Compatibility Single and Dual Tones Detected U.S. Busy-Detect Output Voice-Detect Output Wide Dynamic Range > 40dBm Low Supply Current (0.3mA/0.5mA) Low Supply Voltage (3.3V/5.0V) Standard 3.58MHz Xtal Applications Automatic Calling Products XTAL/ CLOCK XTAL / CLOCK OSCILLATOR V DD V SS XTAL ENABLE DETECT1 SIGIN SLICER SIGNAL ANALYZER CONTROL LOGIC DETECT2 The MX633 is a low cost, low power device that uses signal processing techniques to detect audible tone signals such as Dial, Ringing, Busy and other conditions found when placing a call throughout the world s telecom systems. Detection of these call progress stages is essential to the proper operation of automatic calling products. The MX633 adds new features to Call Progress monitoring. It detects and indicates the U.S. Busy tones, reducing the need to measure tone cadence to identify U.S. Busy. It also detects and indicates voice and other signals from Call Progress tones, reducing voice-falsing and adding voice-answer as a connection prompt. The MX633 may be used with a 3.0V to a 5.5V supply and is available in the following package styles: 8-pin PDIP (MX633P) and 16-pin SOIC (MX633DW).

Call Progress Tone Detector 2 MX633 - PRELIMINARY INFORMATION CONTENTS Section... Page 1. Block Diagram... 3 2. Signal List... 4 3. External Components... 5 4. General Description... 6 4.1 Glossary... 6 4.2 Overall Function Description... 6 4.3 Block Diagram Description (Reference Figure 1)... 6 4.3.1 Slicer...6 4.3.2 Signal Analyzer...6 4.3.3 Control Logic...7 4.3.4 Xtal/Clock Oscillator...7 4.4 Decode Output Truth Table... 7 5. Performance Specification... 7 5.1 Electrical Performance... 7 5.1.1 Absolute Maximum Ratings...7 5.1.2 Operating Limits...8 5.1.3 Operating Characteristics...8 5.1.4 Timing...9 5.2 Packaging... 11 MX COM, Inc. reserves the right to change specifications at any time and without notice

Call Progress Tone Detector 3 MX633 - PRELIMINARY INFORMATION 1. Block Diagram C1 XTAL/ CLOCK V DD R1 X1 XTAL / CLOCK OSCILLATOR V SS C4 C2 XTAL ENABLE DETECT1 C3 SIGIN SLICER SIGNAL ANALYZER CONTROL LOGIC DETECT2 Figure 1: Block Diagram

Call Progress Tone Detector 4 MX633 - PRELIMINARY INFORMATION 2. Signal List Package / Pin No. Signal Type Description P DW 1 2 XTAL/CLOCK input Input to the on-chip oscillator, for external Xtal circuit or clock 2 3 XTAL output Output of the on-chip oscillator inverted 3 5 ENABLE input A logic 1 applied to this input enables the decoder and detection outputs. A logic 0 pulse of at least 1µs applied to this input resets the decoder circuits and forces both DETECT1 and DETECT2 outputs to a logic 0. 4 7 DETECT1 output When a Call Progress signal is detected, DETECT1 output state changes to a logic 1 5 10 SIGIN input Signal input. Signals to this pin should be ac coupled. The dc bias of this pin is set internally. 6 12 V SS power Negative supply 7 13 DETECT2 output Output used in conjunction with DETECT1. When a Call Progress High Band signal is detected and DETECT1 output state is a logic 1, then DETECT2 output state changes to a logic 1. When a Non Call Progress signal is detected and DETECT1 output state is a logic 0, then DETECT2 output state changes to a logic 0. 8 15 V DD power Positive supply. This pin should be bypassed to V SS by a capacitor mounted close to the device pins. Table 1: Signal List

Call Progress Tone Detector 5 MX633 - PRELIMINARY INFORMATION 3. External Components C1 XTAL/ CLOCK 1 8 V DD C4 R1 X1 C2 XTAL ENABLE 2 3 MX633P 7 6 DETECT2 V SS DETECT1 4 5 SIGIN C3 Figure 2: Recommended External Components R1 1 MΩ ±10% C1 33pF ±20% C2 33pF ±20% C3 560pF at 3.3V DD 1nF at 5.0V DD ±20% C4 1.0µF ±20% X1 Note 1 3.579545MHz refer to sec.5.1 Table 2: Recommended External Components Notes: 1. For best results, a crystal oscillator design should drive the clock inverter input with signal levels of at least 40% of V DD, peak to peak. Tuning fork crystals generally cannot meet this requirement. To obtain crystal oscillator design assistance, consult your crystal manufacturer.

Call Progress Tone Detector 6 MX633 - PRELIMINARY INFORMATION 4. General Description The following Glossary and Decode Truth Table (found in section 4.4), describe the MX633 decoding features and functions. 4.1 Glossary Call Progress Tones: The single and dual frequency tones in the range 350Hz to 620Hz specified widely for call progress signaling. Call Progress Band: The nominal range 340Hz to 650Hz within which the MX633 will detect Call Progress tones. The detection algorithm requires that the tones have the characteristics typical of Call Progress Tones. Call Progress Low Band: The nominal range 340Hz to 490Hz. The MX633 will detect single or dual tones falling entirely within this range as Call Progress Low Band tones. Call Progress High Band: The nominal range 600Hz to 650Hz. Single tones in this range, or dual tones (e.g. 480 + 620Hz), having a material frequency component within this range are detected as Call Progress High Band tones. Non Call Progress Signal: A signal falling within the nominal range (a) 200Hz to 800Hz, but NOT within the Call Progress Band, or (b) within the nominal range 200Hz to 800Hz, but NOT meeting the detection requirements when the signal falls in the Call Progress Band. Subject to the duration and other characteristics of such signals, the MX633 will usually interpret this as a Non Call Progress Signal (e.g. speech or other signal activity). Minimum Input Signal: The minimum signal level for the specified tone decoding performance. No Signal: A signal falling outside the nominal range 120Hz to 900Hz or the absence of an input signal. Either will be detected as a No Signal condition. Nominal: Subject to dynamic tolerances within the signal analysis process. Absolute values are not material or adverse to performance. 4.2 Overall Function Description The MX633 Call Progress Tone Detector uses tone detection methods different from those methods commonly found in other Call Progress Tone Detectors. Many Call Progress Tone Detectors 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. Each signal amplitude in this range is checked against a level threshold. Any signal of acceptable level in this frequency band is classified as a Call Progress tone, including speech and noise signals. False outputs caused by speech are commonly indicated by such products and background noise may lead to a stuck detect output. In contrast, the MX633, uses a stochastic signal processing technique. This technique is based on analysis of both the frequency and time domains, with signal amplitude forming a small part in the decision process. This analysis includes checks on whether the signal has a profile that matches international standards for Call Progress tones, speech, noise or other Non-Call-Progress signals. It also checks for U.S. Busy signal tones. 4.3 Block Diagram Description (Reference Figure 1) 4.3.1 Slicer The input signal to the slicer is amplified by a self-biased inverting amplifier. The dc bias of this input is internally set at V DD /2. 4.3.2 Signal Analyzer The frequency range, quality and consistency of the input signal is analyzed by this functional block. To be classified as a call progress signal, the input signal frequencies should lie between 340Hz and 650Hz. The signal to noise ratio must be 16dB or greater and the signal must be consistent over a period of about 140 ms. This decode criteria is continuously monitored and the assessment updated every 7 ms, reference Figure 3. The Signal Analyzer samples the call progress signal at 9.3kHz. Care should be taken to avoid high frequency signals ( 8.4kHz) aliasing into the call progress band.

Call Progress Tone Detector 7 MX633 - PRELIMINARY INFORMATION 4.3.3 Control Logic This block categorizes the nature of the signal into various decode output states and controls the two output pins. See Table 3. 4.3.4 Xtal/Clock Oscillator If the on-chip Xtal oscillator is to be used, then external components X1, R1, C1 and C2 are required. If an external clock source is to be used, then it should be connected to the XTAL/CLOCK input pin and the XTAL pin should be left unconnected. 4.4 Decode Output Truth Table DETECT2 DETECT1 CONDITIONS 0 0 No Signal 0 1 Call Progress Low Band: Will detect 350+440, 400+450, 440+480,400, 425, 440, and 450Hz tones 1 1 Call Progress High Band: Will detect 480+620, 600 and 620Hz tones 1 0 Non Call Progress signal, e.g. voice activity Note: 1. DETECT1 responds to the entire range of call progress tones from 340Hz to 650Hz. Table 3: Decode Output Truth Table 5. Performance Specification 5.1 Electrical Performance 5.1.1 Absolute Maximum Ratings Exceeding these maximum ratings can result in damage to the device. General Min. Max. Units Supply (V DD - V SS ) 0.3 7.0 V Voltage on any pin to V SS 0.3 V DD + 0.3 V Current V DD 30 30 ma V SS 30 30 ma Any other pin 20 20 ma DW / DIP Package Total Allowable Power Dissipation at T AMB = 25 C 800 mw Derating above 25 C 13 mw/ C above 25 C Storage Temperature 55 125 C Operating Temperature 40 85 C

Call Progress Tone Detector 8 MX633 - PRELIMINARY INFORMATION 5.1.2 Operating Limits Correct operation of the device outside these limits is not implied. Notes Min. Max. Units Supply (V DD V SS ) 3.0 5.5 V Xtal Frequency 3.57 3.59 MHz 5.1.3 Operating Characteristics For the following conditions unless otherwise specified: Xtal Frequency = 3.579545MHz, S/N = 16 db, Noise Bandwidth = 5 khz, V DD = 3.3V to 5.0V, V SS = 0V, T AMB = 25 C, 0dB = 775mV RMS. Notes Min. Typ. Max. Units DC Parameters Supply Current I DD (ENABLE = 1) (V DD = 5.0V) 1 0.5 1.0 ma I DD (ENABLE = 1) (V DD = 3.3V) 1 0.3 0.7 ma Enable Input Input Logic 1 Level 2 80% V DD Input Logic 0 Level 2 20% V DD Input Leakage Current (V IN = 0 to V DD ) 2 5.0 5.0 µa Input Capacitance 2 10.0 pf Detect Output Output Logic 1 Level (l OH = 120µA) 3 90% V DD Output Logic 0 Level (l OL = 360µA) 3 10% V DD AC Parameters SIGIN pin Input Impedance (from 100Hz to 2kHz at 5.0V) 4 350 kω Input Signal Level 5 40 db Input Signal Dynamic Range 5 40 db Signal to Noise Ratio 16 db Xtal/Clock Oscillator 'High' Input Pulse Width 6 40 ns 'Low' Input Pulse Width 6 40 ns Input Impedance (at 100Hz) 10 MΩ Gain (input = 1mV RMS at 100Hz) 20 db Operating Characteristics Notes: 1. Not including any current drawn from the device pins by external circuitry. 2. ENABLE pin. 3. DETECT1 and DETECT2 pins. 4. Small signal impedance over the frequency range 100Hz to 2000Hz and at 5.0V 5. The input level is not critical as the detector uses a stochastic algorithm. 6. Timing for an external input to the XTAL/CLOCK pin.

Call Progress Tone Detector 9 MX633 - PRELIMINARY INFORMATION 5.1.4 Timing For the following conditions unless otherwise specified: Xtal Frequency = 3.579545MHz, V DD = 3.3V to 5.0V, T AMB =25 C, S/N = 20dB Timing (ref. Figures 3, 4, 5 and 6) Notes Min. Typ. Max. Units t I Call Progress Burst Length Ignored 70 ms t L Burst Length Detected 145 ms t GI Call Progress Tone Gap Length Ignored 1 20 ms t GD Call Progress Tone Gap Length Detected 1 40 ms t RP Call Progress Tone Response Time 2 145 ms t DRP Call Progress Tone De-response Time 145 ms t GDR Gap Detected Recorded 3 6 ms t NG Non Call Progress Signal Gap Length Ignored 4 80 ms t NRP Non Call Progress Signal Response Time 145 ms t NDRP Non Call Progress Signal De-response Time 80 ms t CH State Change 0 ms t V DETECT1 and DETECT2 Response Time 5 145 ms Timing Notes: 1. Only applies to bursts of the same frequency. 2. For dual tones in 16dB SNR the Response Time may be longer. 3. To acknowledge a short tone gap 40 ms, No Signal is indicated for a minimum of 6ms. 4. If the gap > 90 ms, a No Signal state will be decoded. 5. Time between a stable XTAL/CLK and a valid DETECT1 and DETECT2 state when ENABLE is high. t I t L t GD t GI SIGIN No Signal Call Progress Low Band Call Progress High Band Call Progress High Band Call Progress High Band t RP ENABLE t RP t DRP t GDR DETECT1 t RP t DRP DETECT2 Figure 3: Timing Diagram: Call Progress Tone (s)

Call Progress Tone Detector 10 MX633 - PRELIMINARY INFORMATION t I t L t NG SIGIN Non Call Progress Signal Non Call Progress Signal No Signal ENABLE DETECT1 0 LEVEL t NRP t NDRP DETECT2 Figure 4 : Timing Diagram: Non Call Progress Signal SIGIN No Signal Call Progress Low or High Band Non Call Progress Signal Call Progress Low or High Band ENABLE t RP t CH t RP DETECT1 t NRP DETECT2 Figure 5 : Timing Diagram: Call Progress Tone (s) to Non Call Progress Signal t V DETECT 1 DETECT 2 indeterminate signal valid signal XTAL/CLOCK t S = the time at which XTAL/CLOCK becomes stable Figure 6: Timing Diagram: DETECT 1 and DETECT 2 Response Time when ENABLE is high

Call Progress Tone Detector 11 MX633 - PRELIMINARY INFORMATION 5.2 Packaging A DIM. Package Tolerances MIN. TYP. MAX. PIN1 K H L J1 P J F M B K1 C E1 Y T E A B C E E1 F H J J1 K K1 L M P T Y 0.346 (8.790) 0.240 (6.10) 0.145 (3.68) 0.400 (10.16) 0.260 (6.60) 0.200 (5.06) 0.390 (9.87). 0.300 (7.62) 0.290 (7.37) 0.325 (8.22) 0.30 (7.62) 0.015 (0.38) 0.040 (1.01) 0.015 (0.38) 0.023 (0.58) 0.045 (1.14) 0.065 (1.65) 0.060 (1.52) 0.060 (1.52) 0.121 (3.07) 0.150 (3.81) 0.020 (0.51) 0.033 (0.84) 0.100 (2.54) 0.008 (0.20) 0.015 (0.38) 7 NOTE : All dimensions in inches (mm.) Angles are in degrees Figure 7 : 8-pin PDIP Mechanical Outline: Order as part no. MX633P Package Tolerances ALTERNATIVE PIN LOCATION MARKING H Y PIN 1 J P A C K B X E W T L Z DIM. MIN. TYP. MAX. A B C E H 0.395 (10.03) 0.286 (7.26) 0.093 (2.36) 0.390 (9.90) 0.003 (0.08) 0.413 (10.49) 0.299 (7.59) 0.105 (2.67) 0.419 (10.64) 0.020 (0.51) J 0.013 (0.33) 0.020 (0.51) K 0.041 (1.04) L 0.016 (0.41) 0.050 (1.27) P 0.050 (1.27) T 0.009 (0.23) 0.0125 (0.32) W 45 X 0 10 Y 5 7 Z 5 NOTE : All dimensions in inches (mm.) Angles are in degrees Figure 8 : 16-pin SOIC Mechanical Outline: Order as part no. MX633DW

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 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 CML Microcircuits (USA) Inc. COMMUNICATION SEMICONDUCTORS 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 CML Microcircuits (Singapore)PteLtd COMMUNICATION SEMICONDUCTORS 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