Order this document by MC145444/D SEMICONDUCTOR TECHNICAL DATA Advance Information MC145444 is a silicon gate CMOS frequency shift keying (FSK) modem intended for use with telemeter systems or remote control systems over the telephone network. This device is compatible with CCITT V.21 and contains the entire circuit that provides a full–duplex or half–duplex 300–baud data communication over a pair of telephone lines. This device also includes the DTMF generator and call progress tone detector (CPTD). The differential line driver has the capability of driving 0 dBm into a 600 Ω load with a single + 5 V power supply. The transmit level is controlled by the programmable attenuator in 1 dB steps. Devices functions are controlled through a 3–wire serial interface. • • • • • • • • • Capable of Driving 0 dBm into a 600 Ω Load DTMF Generator On–Chip Imprecise Call Progress Detector On–Chip A Transmit Attenuator Programmable in 1 dB Steps 3–Wire Serial Interface Compatible with CCITT V.21 2100 Hz Answer Tone Generator On–Chip Analog Loopback Configuration for Self Test Simplex, Half–Duplex, and Full–Duplex Operation 20 H SUFFIX PLASTIC DIP CASE 804 1 DW SUFFIX SOG PACKAGE CASE 751D 20 1 ORDERING INFORMATION MC145444P Plastic DIP MC145444DW SOG Package PIN ASSIGNMENT RxBO 1 20 RxGC FTLC 2 19 RxA GNDA 3 18 TxA1 CDA 4 17 TxA2 GND 5 16 DSI TLA 6 15 VCC X1 7 14 ENB X2 8 13 SCK SD 9 12 DATA RxD 10 11 TxD This document contains information on a new product. Specifications and information herein are subject to change without notice. REV 0 8/95 Motorola, Inc. 1995 MOTOROLA MC145444 1 BLOCK DIAGRAM RxBO RxA + FTLC ANTI–ALIAS FILTER – S/H MUX LOW–BAND BPF MUX MUX HIGH–BAND BPF MUX/ MIXING 65 k AC AMP FSK DEMODULATOR RxD CARRIER/CPT DETECTOR SD CDA RxGC 30 k TxD FSK MODULATOR DSI LEVEL CONTROL TLA Rf DTMF GENERATOR SMOOTHING FILTER R _ + 20 k TxA1 CONTROL LOGIC –1 ENB 15–BIT LATCH POWER–ON RESET DATA SCK 15–BIT SHIFT REGISTER CLOCK GENERATOR X1 TxA2 ANALOG GROUND GENERATOR X2 GNDA Symbol Value Unit VCC – 0.5 to + 7.0 V DC Input Voltage Vin – 0.5 to VCC + 0.5 V DC Output Voltage Vout – 0.5 to VCC + 0.5 V IIK, IOK ± 20 mA Iout ± 25 mA GND VCC MAXIMUM RATINGS* (Voltages Referenced to VSS) Rating DC Supply Voltage Clamp Diode Current per Pin DC Current per Pin Power Dissipation PD 500 mW Storage Temperature Range Tstg – 65 to + 150 °C RECOMMENDED OPERATING CONDITIONS Parameter Symbol Min Typ Max Unit VCC 4.5 5 5.5 V DC Input Voltage Vin 0 — VCC V DC Output Voltage Vout 0 — VCC V tr 0 — 500 ns DC Supply Voltage Input Rise Time Input Fall Time Crystal Frequency Operating Temperature Range MC145444 2 tf 0 — 500 ns fosc — 3.579545 — MHz TA – 20 25 70 °C MOTOROLA DC ELECTRICAL CHARACTERISTICS (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Characteristic Input Voltage Output Voltage Min Typ Max Unit H Level Symbol VIH 3.15 — — V L Level VIL — — 1.1 H Level VOH IOH = 20 µA VCC – 0.1 VCC – 0.01 — L Level VOL IOL = 20 µA IOL = 2 mA — — 0.01 — 0.1 0.4 Vin = VCC or GND — ± 1.0 ± 10.0 µA ICC FSK Mode — 8 — mA ICC Power–Down Mode 1 — — 300 µA ICC Power–Down Mode 2 — — 1 µA Min Typ Max Unit 974 980 986 Hz Input Current DATA, SCK, E, TxD Iin Quiescent Supply Current Power–Down Supply Current Conditions V TRANSMIT CARRIER CHARACTERISTICS (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Symbol Characteristic Carrier Frequency Channel 1 Mark ‘‘1’’ Conditions f1M 1174 1180 1186 1644 1650 1656 f2S 1844 1850 1856 Answer Tone fans 2094 2100 2106 Transmit Carrier Level VO* — 6 — dBm — – 46 — dBm Carrier Frequency Channel 2 Space ‘‘0’’ f1S Mark ‘‘1’’ f2M Space ‘‘0’’ Second Harmonic Energy V2h* Out–of–Band Energy VOE* C l Frequency F Crystal 3.579545 MHz Attenuator = 0 dB RTLA = ∞ Figure 1 dBm * VTXA1 – VTXA2, RL = 1.2 kΩ TRANSMIT ATTENUATOR CHARACTERISTICS (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Characteristic Symbol Conditions Min Typ Max Unit Attenuator Range ARNG 0 — 15 dB Attenuator Accuracy AACC – 0.5 — + 0.5 dB Min Typ Max Unit 50 — — kΩ – 48 — – 12 dBm — – 44 — dBm — – 47 — 2 — — dB CD1 = 0, CD0 = 0 — 450 — ms CD1 = 0, CD0 = 1 — 15 — CD1 = 0, CD1 = 1 — 15 — CD1 = 1, CD0 = 1 — 80 — CD1 = 0, CD0 = 0 — 30 — CD1 = 0, CD0 = 1 — 30 — CD1 = 0, CD0 = 1 — 15 — CD1 = 1, CD0 = 1 — 10 — RECEIVER CHARACTERISTICS (Includes Hybrid, Demodulator and Carrier Detector) (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Characteristic Symbol Input Impedance RIRX Receiver Carrier Amplitude VIRX Carrier Detect OFF to ON VCDON Threshold ON to OFF VCDOF Hysterisis (VCDON – VCCDOF) Carrier Detect Timing RxA Pin (Pin 19) CDA = 1.2 V 1 0 kHz fin i = 1.0 HVS OFF to ON TCDON ON to OFF TCDOFF MOTOROLA Conditions MC145444 3 BAND–PASS FILTER CHARACTERISTICS (RxA to FTLC) (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Characteristic Symbol FTLC Output Impedance Conditions Min Typ Max Unit 10 — 50 kΩ — 50 — dB — 10 — dB Low–Band Filter 930 – 1230 Hz — 700 — µs High–Band Filter 1600 – 1900 Hz — 800 — Min Typ Max Unit — 3 — dBm — 4 — ROFT Adjacent Channel Rejection REJ Pass–Band Gain VRXA = – 12 dBm GPAS Group Delay DTMF CHARACTERISTICS (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Symbol Characteristic Tone Output Level Low Group Vfl* High Group Vfh* High Group Pre Emphasis PE DTMF Distortion DIST ∆fV DTMF Frequency Variation Out–of–Band Energy Conditions Attenuator = 0 dB RTLA = ∞ Crystal Frequency 3.579545 MHz 0 — 3 dB — 5 — % –1 — 1 % VOE* Setup Time Figure 1 tosc dB — 4 — ms Min Typ Max Unit * VTXA1 – VTXA2, RL = 1.2 kΩ CPTD CHARACTERISTICS (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Symbol Characteristic Conditions Band–Pass Filter Center Frequency fc — 400 — Hz Band–Pass Filter – 3 dB Band Width ∆ BW — 140 — Hz OFF to ON VTDON — – 44 — dBm ON to OFF VTDOF — – 47 — OFF to ON TTDON — 10 — ON to OFF TTDOF — 25 — Tone Detect Level Tone Detect Timing CDA = 1 1.2 2V fin = 400 Hz ms DEMODULATOR CHARACTERISTICS (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Characteristic Bit Bias Bit Error Rate Symbol Conditions Min Typ Max Unit ID Input Level = – 24 dBm — 5 — % BER Input Level = – 24 dBm CCITT Line Simulation 511 Bit Pattern S/N = 5 dB — 0.00001 — — Min Typ Max Unit 50 — — ns 50 — — ns SWITCHING CHARACTERISTICS (VCC = + 5.0 V ± 10%, TA = – 20 to + 70°C) Characteristic Setup Times Symbol DATA to SCK tsu SCK to ENB Hold Time Conditions SCK to DATA th 50 — — ns ENB to SCK trec 50 — — ns Input Rise Time tr — — 2 µs Input Fall Time tf — — 2 µs tw 50 — — ns Recovery Time Input Pulse Width MC145444 4 ENB, SCK MOTOROLA 0 3.4 k 4 k 16 k 256 k f (Hz) — VCC — GND DATA 50% tsu 0 th LAST CLK SCK – 25 50% tsu – 15 dB/OCT. — VCC — GND FIRST CLK trec ENB — VCC — GND 50% PREVIOUS DATA LATCHED – 55 tr ENB Figure 1. Out–of–Band Energy PIN DESCRIPTION VCC Positive Power Supply (Pin 15) This pin is normally tied to the + 5.0 V. A 0.1 µF decoupling capacitor should be used. GND Ground Pin (Pin 5) This pin is normally tied to 0 V. GNDA Analog Ground (Pin 3) Analog ground is internally biased to (VCC – VSS) / 2. It should be tied to ground through a 0.1 µF and 100 µF capacitor. X1 Crystal Oscillator Output (Pin 7) Connecting a 3.579545 MHz ± 0.1% crystal between X1 and X2 will cause the transmit frequencies to be within ± 64 MHz of nominal. X1 is capable of driving several CMOS gates. An external clock may be applied to X2. X1 should then be left open. X2 Crystal Oscillator Input (Pin 8) Refer to X1. SCK Shift Resister Clock Input (Pin 13) This pin is the clock input for the 15–bit shift register. Serial data is loaded into the shift register on the rising edge of this clock. DATA Serial Data Input (Pin 12) This pin is the 15–bit serial data input. This data determines the mode, DTMF signal, transmit attenuation, carrier detect time, channel, and transmit squelch. MOTOROLA 50% tf 50% — VCC — GND Figure 2. Switching Characteristics ENB Enable Input (Pin 14) Data is loaded into the 15–bit shift register when this pin is at a logic low. When this pin transitions from a logic high to low, the data is transferred to the internal latch on the falling edge of ENB. New data loaded into the shift register will not affect the device operation until this pin transitions from high to low. (See Figure 2.) TxD Transmit Data Input (Pin 11) This pin is the transmit data input, The mark frequency is generated when this pin is at the logic high level. The space frequency is generated when the pin is at a logic low. RxD Receive Data Output (Pin 10) This pin is the receive data output. A high logic level of this pin indicates that the mark carrier frequency has been received, and a low logic level indicates the space carrier frequency has been received. SD Carrier/Call Progress Tone Detect (Pin 9) This pin is the output from the carrier detector or call progress tone detector. This pin works as a carrier detector in the FSK mode and as the call progress tone detector in the CPTD mode. The output goes to a logic low level when the input signal reaches the minimum threshold of the detect level that is adjusted by the CDA voltage. When SD = H, the receive data output (RxD) is clamped high to avoid errors that may occur with loop noise. The SD pin is also clamped high in the other modes except during the power–down mode. TxA1 Non–Inverting Transmit Analog Carrier Output (Pin 18) This pin is the line driver non–inverting output of the FSK and tone transmit analog signals. A + 6 dBm (max) differential output voltage can be obtained by connecting a 1.2 kΩ load resistor between Tx1 and Tx2. Attention must be set so as not to exceed this level when an external input is added to the DSI pin. A telephone line (600 Ω) is driven through an external 600 Ω resistor. In this case, the output level becomes about half of differential output. MC145444 5 TxA2 Inverting Transmit Analog Carrier Output (Pin 17) This pin is the line driver inverting output. The signal is equal in magnitude, but 180° out of phase with the TxA1 (refer to TxA1). RxA Receive Signal Input (Pin 19) This pin is the receive signal input. The pin has an input impedance of 50 kΩ (min). RxGC Receive Gain Adjust (Pin 20) This pin is used to adjust the receive buffer gain. To adjust the gain, the signal from the RxBO through a divider is added as a feedback. This pin may be held open when the gain adjustment is not needed. RxBO Receiver Buffer Output (Pin 1) This pin is the receive buffer output. DSI Driver Summing Input (Pin 16) This pin is the inverting input of the line driver. An external signal is transmitted through an external series resistor RDSI. The differential gain GDSI = (VTXA1 – VTXA2)/VDSI is determined by the following equation. GDSI = – 2Rf / RDSI, Rf ≈ 20 kΩ DSI should be left open when not used. CDA Carrier Detect Level/CPTD Level Control (Pin 4) The carrier/call progress tone detect level is programmed with a CDA pin voltage. When this pin is held open, the CDA voltage is set to 1.2 V with an internal divider. The detect level is set at – 44 dBm (typ) for off to on, and – 47 dBm (typ) for on to off. The minimum hysteresis is 2 dB. This pin has a very high input impedance so it should be connected to GND with a 0.1 µF capacitor to keep it well regulated. An external voltage may be applied to this pin to adjust the carrier detect threshold. The following equations may be used to find the CDA voltage required for a given threshold voltage. SERIAL INTERFACE The following six functions are set up with the 15–bit serial data. FUNCTION MODE : M2 M1 M0 TRANSMIT ATTENUATOR : A3 A2 A1 A0 TRANSMIT SQUELCH : SQ TONE FREQUENCY : T3 T2 T1 T0 CHANNEL : CH CARRIER DETECT TIME : CD1 CD0 Figure 3 presents the 15–bit serial data timing, starting with the carrier detect time, CD1, followed by the channel, the tone frequency, the transmit squelch, the transmit attenuator, and the function mode. This data is loaded into the internal shift register at the rising edge of the SCK signal and latched at the falling edge of the ENB signal. FUNCTION MODE Modes are selected from the following 3–bit data (M2 – M0, see Table 1). Table 1. Function Mode Truth Table M2 M1 M0 Function Mode 0 0 0 FSK 0 0 1 Analog Loopback 0 1 0 CPTD 0 1 1 Answer Tone 1 0 0 DTMF 1 0 1 Single Tone 1 1 0 Power–Down 1 1 1 1 Power–Down 2 The following paragraphs describe each function. Table 2 presents each output status. VCDA = 245 × Von FSK Mode VCDA = 347 × Voff The transmitter and the receiver work as a FSK modulator/demodulator. The SD pin output is the carrier’s detect signal. FTLC Filter Test (Pin 2) This pin is a high–impedance filter output. It may be used to check the receive filter. This pin also may be used as a demodulator input. In normal operation, this pin is connected to the GNDA through a 0.1 µF bypass capacitor. This pin handles very small signals so care must be used with the capacitor’s wiring. TLA Transmit Carrier Level Adjust (Pin 6) This pin is used to adjust the transmit carrier level that is determined by the value of the resistor (RTLA) connected MC145444 6 between this pin and GND. The maximum transmit level is obtained when this pin is connected to GND (RTLA = 0). Analog Loopback Mode TxA1 connects to the receiver internally and FSK signals are demodulated. The frequency of the receiver is set up with the same frequency as the transmitter. The SD pin output is the carrier detect signal. An IC self test is supported with this function. CPTD Mode The receiver detects a 400 Hz call progress tone. The detect signal comes from the SD pin. The transmitter is disabled. MOTOROLA DATA CD1 CD0 CH T3 T2 T1 T0 SQ A3 A2 A1 A0 M2 M1 M0 SCK E Figure 3. Serial Data Timing Table 2. Output Status Output F Function i M Mode d RxD SD TxA1, TxA2 Received Digital Data Carrier Detect FSK CPTD H CPTD VCC/2 Answer Tone H H Answer Tone DTMF H H DTMF Tone Single Tone H H Single Tone High–Z High–Z High–Z FSK Analog Loopback Power–Down 1, 2 Answer Tone Mode Power–Down Mode 2 The transmitter works as 2100 Hz answer tone generator. The receiver is disabled. All circuits including the oscillator stop working and all outputs go to the high impedance state. The supply current decreases to 1.0 µA (max). DTMF Mode The transmitter works as a DTMF tone generator. The receiver is disabled. Single Tone Mode The transmitter output is one of the DTMF eight frequencies. The receiver is disabled. Transmit Attenuator Four–bit serial data (A3 – A0) sets up the analog transmit level in the FSK, answer tone, DTMF, analog loopback, and single tone mode. The range of the transmit attenuator is 0 – 15 dB in 1 dB steps. The external signal (DSI) is not affected by this attenuator. Power–Down Mode 1 TONE FREQUENCY Internal circuits except the oscillator are disabled, and all outputs except the X1 pin go to the high impedance state. The supply current decreases to 300 µA (max). MOTOROLA The DTMF tones or the single tone mode is selected by the 4–bit serial data (T3 – T0). MC145444 7 Table 3. Transmit Attenuator Truth Table A3 A2 A1 A0 Attenuation (dB) 0 0 0 0 0 0 0 0 1 1 0 0 1 0 2 0 0 1 1 3 0 1 0 0 4 0 1 0 1 5 0 1 1 0 6 0 1 1 1 7 1 0 0 0 8 1 0 0 1 9 1 0 1 0 10 1 0 1 1 11 1 1 0 0 12 1 1 0 1 13 1 1 1 0 14 1 1 1 1 15 Table 4. Tone Frequency Truth Table Tone Frequency (Hz) DTMF Mode MC145444 8 T3 T2 T1 T0 Low Group High Group Keyboard Equivalent Si l Single Tone Mode 0 0 0 0 941 1633 D 941 0 0 0 1 697 1209 1 697 0 0 1 0 697 1336 2 697 0 0 1 1 697 1477 3 697 0 1 0 0 770 1209 4 770 0 1 0 1 770 1336 5 770 0 1 1 0 770 1477 6 770 0 1 1 1 852 1209 7 852 1 0 0 0 852 1336 8 1336 1 0 0 1 852 1477 9 1477 1 0 1 0 941 1336 0 1336 1 0 1 1 941 1209 * 1209 1 1 0 0 941 1477 # 1477 1 1 0 1 697 1633 A 1633 1 1 1 0 770 1633 B 1633 1 1 1 1 852 1633 C 1633 MOTOROLA TRANSMIT SQUELCH Von The 1–bit serial data (SQ) controls the transmit analog signal. The FSK signal, DTMF tones, single tone, and answer tone are disabled. The external signal to the DSI will be transmitted at that time. The internal line driver works at all times except during the power–down mode. SQ Squelch 1 Enable 0 Disable Voff RxA ton toff SD CHANNEL Figure 4. Carrier Detect Timing The transmit and receive channel is set up with a 1–bit serial data (CH) when the function mode is either in FSK or analog loopback. When the function mode is either on the FSK or analog loopback mode, the transmit and receive channel is set up with a 1–bit serial data (CH). Table 5. Carrier Detect Time Truth Table Carrier Detect Time (Typ) CD1 CD0 ton (ms) toff (ms) 0 0 450 30 CH Channel 0 1 15 30 1 1 (Originate) 1 0 15 15 0 2 (Answer) 1 1 80 10 POWER–ON RESET CARRIER DETECT TIME The carrier detect time (see Figure 4 and Table 5) is set by 2–bit serial data (CD1, CD0). ton indicates the amount of time the carrier is greater than Von threshold must be present before SD goes low. toff, on the other hand, indicates the amount of delay time SD goes high after the carrier level becomes lower than Voff threshold. MOTOROLA When the power is switched on, this device has the following conditions. Function Mode FSK Transmit Attenuator 0 dB Transmit Squelch Enable Channel 1 (Originate) MC145444 9 100 µF 0.1 µF 10 Ω 600 : 600 TxA2 GNDA TIP 600 Ω * TxA1 RING FTLC 0.1 µF RxA RxGC CDA RxBO 0.1 µF TxD RxD SD I/O PORT TLA MCU DATA SCK ENB DSI X1 3.57945 MHz 0.1 µF X2 VCC +5V GND * LINE PROTECTION CIRCUIT DIGITAL GROUND ANALOG GROUND Figure 5. Application Circuit MC145444 10 MOTOROLA PACKAGE DIMENSIONS H SUFFIX PLASTIC DIP CASE 804–01 20 11 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. DIMENSION B DOES NOT INCLUDE MOLD FLASH. 3. DIMENSION L TO CENTER OF LEADS WHEN FORMED PARALLEL. 4. CONTROLLING DIMENSION: INCH. B 1 10 L –A– C K H G –T– N F SEATING PLANE M J D 20 PL 0.25 (0.010) M T A M DIM A B C D F G H J K L M N INCHES MILLIMETERS MIN MAX MIN MAX 0.930 0.970 23.63 24.63 0.240 0.260 6.10 6.60 0.150 0.170 3.81 4.31 0.015 0.022 0.38 0.56 0.050 0.070 1.27 1.78 0.100 BSC 2.54 BSC 0.030 NOM 0.76 NOM 0.009 0.013 0.23 0.33 0.115 0.140 2.93 3.55 0.300 BSC 7.62 BSC 0_ 15 _ 0_ 15 _ 0.020 0.040 0.51 1.02 DW SUFFIX SOG PACKAGE CASE 751D–04 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DIMENSIONS A AND B DO NOT INCLUDE MOLD PROTRUSION. 4. MAXIMUM MOLD PROTRUSION 0.150 (0.006) PER SIDE. 5. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.13 (0.005) TOTAL IN EXCESS OF D DIMENSION AT MAXIMUM MATERIAL CONDITION. –A– 20 11 –B– 10X P 0.010 (0.25) 1 M B M 10 20X D 0.010 (0.25) M T A B S J S F R C –T– 18X MOTOROLA G K SEATING PLANE X 45 _ DIM A B C D F G J K M P R MILLIMETERS MIN MAX 12.65 12.95 7.40 7.60 2.35 2.65 0.35 0.49 0.50 0.90 1.27 BSC 0.25 0.32 0.10 0.25 0_ 7_ 10.05 10.55 0.25 0.75 INCHES MIN MAX 0.499 0.510 0.292 0.299 0.093 0.104 0.014 0.019 0.020 0.035 0.050 BSC 0.010 0.012 0.004 0.009 0_ 7_ 0.395 0.415 0.010 0.029 M MC145444 11 Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. “Typical” parameters can and do vary in different applications. All operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. 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Box 20912; Phoenix, Arizona 85036. 1–800–441–2447 JAPAN: Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, Toshikatsu Otsuki, 6F Seibu–Butsuryu–Center, 3–14–2 Tatsumi Koto–Ku, Tokyo 135, Japan. 03–3521–8315 MFAX: [email protected] – TOUCHTONE (602) 244–6609 INTERNET: http://Design–NET.com HONG KONG: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 MC145444 12 ◊ *MC145444/D* MC145444/D MOTOROLA