NE5900N

Philips Semiconductors Product specification Call progress decoder NE5900 DESCRIPTION The NE5900 call progress decoder (CPD) is a low cost, low power CMOS integrated circuit designed to interface with a microprocessor-controlled smart telephone capable of making preprogrammed telephone calls. The call progress decoder information to permit microprocessor decisions whether to initiate, continue, or terminate calls. A tri-state, 3-bit output code indicates the presence of dial tone, audible ring-back, busy signal, or re-order tones. A front-end bandpass filter is accomplished with switched capacitors. The bandshaped signal is detected and the cadence is measured prior to output decoding. In addition to the three data bits, a buffered bandpass output and envelope output are available. All logic inputs and outputs can interface with LSTTL, CMOS and NMOS. Circuit features include low power consumption and easy application. Few and inexpensive external components are required. A typical application requires a 3.58MHz crystal or clock, 470kΩ resistor, and two bypass capacitors. The NE5900 is effective where traditional call progress tones, PBX tones, and precision call progress tones must be correctly interpreted with a single circuit. PIN CONFIGURATION D1 and N Packages INPUT VREF EXT CLOCK IN/XTAL1 XTAL2 TEST IN CLEAR IN COUNT IN PROGRESS 0V 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 5V ANALOG OUT TRI-STATE ENABLE ENVELOPE BIT 1 BIT 2 BIT 3 DATA VALID TOP VIEW NOTE: 1. SOL — Released in large SO package only. SR01142 Figure 1. Pin Configuration APPLICATIONS FEATURES • Fully decoded tri-state call progress status output • Works with traditional, precision, or PBX call progress tones • Low power consumption • Low cost 3.58MHz crystal or clock • No calibration or adjustment • Interfaces with LSTLL, CMOS, NMOS • Easy application ORDERING INFORMATION DESCRIPTION 16-Pin Plastic Small Outline (SOL) Package 16-Pin Plastic Dual In-Line (DIP) Package • Modems • PBXs • Security equipment • Auto dialers • Answering machines • Remote diagnostics • Pay telephones TEMPERATURE RANGE 0 to +70°C 0 to +70°C ORDER CODE NE5900DK NE5900N DWG # SOT162-1 SOT38-4 1986 May 8 1 853-0842 83667 Philips Semiconductors Product specification Call progress decoder NE5900 BLOCK DIAGRAM ANALOG OUT 0V VREF 5V 10kΩ INPUT FILTER DETECTOR 10kΩ TRI-STATE ENABLE ENVELOPE EXT CLOCK IN/XTAL1 TIMING DECODER TRI-STATE BIT 1 BIT 2 XTAL2 BIT 3 TEST IN CLEAR IN COUNT IN PROGRESS DATA VALID SR01143 Figure 2. NE5900 Block Diagram ABSOLUTE MAXIMUM RATINGS SYMBOL VDD VIN VIN VOUT TSTG TA TSOLD TJMAX Supply voltage Logic control input voltages All other input voltages1 PARAMETER RATING 9 -0.3 to +16 -0.3 to VCC + 0.3 -0.3 to VCC + 0.3 -65 to +150 0 to +70 +300 +150 UNITS V V V V °C °C °C °C Output voltages Storage temperature range Operating temperature range Lead soldering temperature (10s) Junction temperature NOTE: 1. Includes Pin 3 — Ext Clock In 1986 May 8 2 Philips Semiconductors Product specification Call progress decoder NE5900 DC ELECTRICAL CHARACTERISTICS VCC = +3.3V, TA = 25°C; unless otherwise stated. SYMBOL VDD PARAMETER Power supply voltage Quiescent current Input threshold Signal rejection Low frequency2 rejection High frequency2 rejection VIH VIL IIH IIL VIH VIL VOL VOH IOZ Logic 1 level Logic 0 level Logic 1 input current Logic 0 input current Logic 1 input voltage Logic 0 input voltage Logic 0 output voltage Logic 1 output voltage Tri-state leakage TEST CONDITIONS CONDITIONS Pin 16 Pin 14 = VDD Pin 5, 6 = 0V As above with no output loads Pin 1 level, frequency = 460Hz, VDD = VREF Output Pin 13 = VDD Pin 1 level, frequency = 300Hz, VDD = VREF Output Pin 13 = 0V Pin 1 frequency, 0dB max., VDC = VREF Output Pin 13 = 0V Pin 1 frequency, 0dB max., VDC = VREF Output Pin 13 = 0V Pins 6, 14 Pins 6, 14 Pins 3, 6, 14 = VDD Pins 3, 6, 14 = 0V Pin 3 External Clock In/XTAL Pin 3 External Clock In/XTAL ISINK = 1.6mA Pins 7, 9, 10, 11, 12, 13 ISOURCE = 0.5mA Pins 7, 9, 10, 11, 12, 13 VOUT = VDD or 0V Pins 10, 11, 12, 13, Pin 14 = 0V Input Pin 1, 460Hz – 20dB, VDC = VREF Output Pin 15, RLOAD = 1MΩ As above from 300Hz to 630Hz, referenced to 460Hz Pin 1, frequency = 460MHz Pin 2, VDD = 5V Pin 2 Time from removal or application of 460Hz – 20dB (VDC = VREF on Pin 1) to response of Pin 13 800 2.0 0 -1.0 -1.0 VDD – 1 0 0 VDD – 0.4 -3.0 15 0.8 1.0 1.0 VDD 1.0 0.4 VDD 3.0 LIMITS MIN 4.5 TYP 5.0 2.0 -39 MAX 5.5 4.0 -35 -50 180 UNITS V mA dB1 dB1 Hz Hz V V µA µA V V V V µA Filter output gain Filter frequency response Input impedance VREF RREF Reference voltage Reference resistance Envelope response time NOTE: 1. 0dB = 0.775VRMS 2. By design; not tested. 6.5 -1.0 1 2.4 8.5 10.5 1.0 dB dBmo MΩ 2.5 5 38 2.6 V Ω ms The NE5900 uses the signal in the call progress tone passband and the cadence of interrupt rate of the signal to determine which call progress tone is present. Figure 3 shows a detailed block diagram of the NE5900. The signal input from the phone line is coupled through a 470kΩ resistor which, together with two internal capacitors and an internal resistor, form an anti-aliasing filter. This passive low pass filter strongly rejects AM radio interference. Insertion loss is typically 1.5dB at 460Hz. The 470kΩ resistor also provides protection from the transients. The input (Pin 1) DC voltage can be derived from VREF (Pin 2) or allowed to self-bias through a series coupling capacitor (10nF minimum). Following this is a switched capacitor bandpass filter which accepts call progress tones and inhibits tones not in the call progress band of 300Hz to 630Hz. The bandpass limits are determined by the input clock frequency of 3.58MHz. An on-board inverter between Pins 3 and 4 can be used either as a crystal oscillator or as a buffer for an external 3.58MHz clock signal. The switched capacitor filters provide typical rejection of greater than 40dB for frequencies below 120Hz and above 1.6kHz. The decoder responds to signals between 300Hz and 630Hz with a threshold of -39dB typical (0dB = 0.775VRMS). The decoder will not respond to any signal below -50dB or to tones up to 0dB which are below 180Hz or above 800Hz. Dropouts of 20ms or bursts of only 20ms duration are ignored. A gap of 40ms or a valid tone of 40ms is detected. The buffered output of the switched capacitor filter is available at the analog output, Pin 15. A logic output representing the detected envelope of this signal is available at the envelope output, Pin 13. 1986 May 8 3 Philips Semiconductors Product specification Call progress decoder NE5900 At the start of an in-band tone (envelope output goes high), a 2.3 second interval is timed out. Transitions of the envelope during this interval are counted to determine the signal present. At 2.3 seconds, the three bits of data representing this decision are stored in the latch and appear at the outputs. A data valid signal goes high at this time, signaling that the data bits, Pins 10 – 12, can be read. The output code is as follows: Pin 12 Dial Tone Ringing Signal Busy Signal Re-order Tone Overflow 0 1 0 0 1 Pin 11 0 0 1 0 1 Pin 10 0 0 0 1 1 post-dialing interval. Note that the end of dial tone in interpreted as a valid ringing signal. The clear input resets all internal registers and the output latch, and is to be set low after the completion of dialing. The clear input should be pulsed high for proper operation. Recommended pulse width is between 0.2µs and 20ms. If clear is held high when envelope is high, a false output pulse (Pin 13) can result when clear is returned low. For applications where dialing is done by a person rather than by a microprocessor, an uncertainty exists about the number of digits to be dialed (local vs long distance). In such situations it is possible to clear the NE5900 by application of the DTMF signal or dial pulses to the clear pin (Pin 6). When dialing is complete, the device is cleared and ready to respond to the next call progress unit. Enable is held at 5V to enable Pins 10, 11, 12 and 13. When enable is brought low, data valid is also set low. Enable must remain high while the data is also set low. Enable must remain high while the data is being read. The test pin is for production test only and must be kept low in all user applications. The overflow condition occurs in the event that too many transitions occur during the 2.3 second interval. This can result from noise, voice, or other line disturbances not normally present during the BUFFER INPUT ANTI-ALIAS FILTER SC BANDPASS FILTER 5V EXT CLOCK IN/XTAL1 IN/XTAL2 R1 3.58MHz OSCILLATOR LOWPASS FILTER DIGITAL DETECTOR 10kΩ VREF R2 10kΩ 0V CLEAR IN CLOCK DIVIDERS DECODER LOGIC ANALOG DETECTOR TRI-STATE ENABLE ENVELOPE COUNT IN PROGRESS DATA VALID 2.3 SECOND TIMER DECODER LATCHES TRI-STATE BUFFERS BIT 1 BIT 2 BIT 3 SR01144 Figure 3. Detailed Block Diagram CPD Figure 4 shows a typical application of the call progress decoder. In this application only one external component is needed an no microprocessor activity other than clear is required. Figure 5 shows the recommended direct interface to the telephone line. Bus connection is possible by utilizing tri-state, and internal timing is accomplished with a 3.58MHz crystal. The designer can utilize the input signal, clock, bus, or microprocessor interface which best serves the application. Figure 6 gives a typical timing diagram for the application of Figures 4 and 5. 1986 May 8 4 Philips Semiconductors Product specification Call progress decoder NE5900 1 TO EAR-PIECE 470kΩ 2 3 4 5 6 7 OPTIONAL CAPACITIVE INPUT 8 NE5900 16 15 14 13 12 11 10 9 5V 3.58MHz IN 10nF 470kΩ 1 2 10nF ENVELOPE BIT 1 BIT 2 BIT 3 INTERRUPT START CLEAR SR01145 Figure 4. Typical Application IN1 C1 10nF R5 R1 100kΩ + AV – R4 100kΩ R3 100kΩ R6 10MΩ 3.58MHz 5 6 7 8 470kΩ 1 2 3 4 R2 100kΩ NE5900 12 11 10 9 INTERRUPT DECODED OUTPUTS TO PROCESSOR 16 15 14 13 ENABLE ENVELOPE 5V IN2 C2 10nF START C3 1µF CLEAR SR01146 Figure 5. Typical Two-Wire Application 1986 May 8 5 Philips Semiconductors Product specification Call progress decoder NE5900 INPUT CLEAR ENVELOPE DATA VALID BIT 1 BIT 2 BIT 3 COUNT IN PROGRESS 1986 May 8 ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉ ÉÉÉÉÉÉ ÉÉÉÉÉÉ 38ms TYPICAL 2.27 SECONDS 1.1 SECONDS 42ms TYPICAL SR01147 Figure 6. 6 Philips Semiconductors Product specification Call progress decoder NE5900 TYPICAL PERFORMANCE CHARACTERISTICS 3.0 3.0 SUPPLY CURRENT (mA) (Pin 16) 2.5 2.0 1.5 1.0 0.5 0.0 3.0 3.5 4.0 4.5 5.0 5.5 SUPPLY VOLTAGE (VDD) (Pin 16) OUTPUT CURRENT (mA) (Pin 13) -2.5 -5.0 -7.5 -10.0 -12.5 -15.0 0 1 2 3 4 5 OUTPUT VOLTAGE (Pin 13) SR01148 SR01151 Figure 7. Power Supply Current vs VDD Figure 10. Output Voltage Current Curve Digital Output High OUTPUT VOLTAGE (Pin 4) 4 LEVEL RELATIVE TO 460Hz (dBV) (Pin 15) 5 0 -20 3 2 -40 1 0 0 1 2 3 4 5 INPUT VOLTAGE (Pin 3) -60 100 1000 FREQUENCY (40 TO 4000Hz) SR01149 SR01152 Figure 8. Voltage Transfer Curve Figure 11. Filter Frequency Response OUTPUT CURRENT SINK (mA) (Pin 13) 50 -20 -25 Pin 1 LEVEL (dB) 0 2 3 4 1 OUTPUT VOLTAGE (Pin 13) 5 -30 -35 -40 -45 40 30 20 10 0 -50 300 350 SR01150 400 450 500 550 FREQUENCY (Hz) 600 650 SR01153 Figure 9. Digital Output Low Figure 12. Typical Threshold 1986 May 8 7