U4055B/U4055B1 Low-Voltage Electronic Speech Circuit with Dialer Interface Description The U4055B electronic speech circuit is a linear integrated circuit for use in telephone and other line fed terminal equipment. It replaces the common speech circuit with carbon microphone, hybrid transformer, sidetone equivalent and ear protection rectifiers. A low-cost electrodynamic transducer is used as the earphone. It contains all components necessary for amplification of signals and adaption to the line. Features D An electronic circuit replaces the microphone hybrid transformer D Symmetrical input for dynamic or piezo microphone D High performance through the use of dynamic x transducers as the earphone (non-linear distortion 2 %) D Automatic line loss compensation D D D D DTMF interface with muting Supply voltage for dialer High range of line feeding current Input resistance independent of line current and sidetone suppression circuit. D Built-in ear protection by earphone voltage limiter D Operation possible from 8 mA U4055B1: High level mute; U4055B: Low level mute Figure 1. Block diagram and pin connection TELEFUNKEN Semiconductors Rev. A1, 06-May-96 1 (10) Preliminary Information U4055B/U4055B1 Pin Description Pin 1, 2 3 4 5 6 7, 8 9 10 Symbol Function H1 and H2 The push-pull complementary outputs of the receive amplifier. Dynamic transducers with a minimum impedance of 100 W can be directly driven by these outputs. GND Ground. ST The output of the sidetone cancellation signal, which requires a balanced impedance of 8–10 times the subscribers line impedance to be connected to Pin 13. CK2 Input to the line output driver amplifier. Transmit a.g.c. applied to this stage. CK1 The transmit pre-amp output respective of the DTMF output which is normally capacitively coupled to Pin 5. MIC 1, Inputs of symmetrical MIC 2 microphone amplifier with high common mode rejection ratio. DTMF IN The DTMF input has an internal resistor connected to ground. It provides the load resistor for the emitter of a CMOS DTMF generator. This input is only active when MUTE (Pin 10) is pulled high or MUTE is pulled low. MUTE or The MUTE input must be pulled MUTE at least at 1.5 V (MUTE) or at less than 0.5 V (MUTE) to mute the MIC Amp. and Audio Amp. and enable DTMF IN. Pin 11 Symbol V+ 12 REC IN 13 VL 14 RDC 15 VI 16 RAGC 2 (10) Preliminary Information Function Regulated output voltage of 2.7 V for biasing a DTMF generator activated by MUTE. The receive amplifier input. The receiving amplification is regulated of an a.g.c. Positive supply voltage input to the device. This input should be connected to the positive output of the polarity guard. The current through this pin is modulated by the transmit signal. An external resistor (2 W) is required from this pin to GND to control the dc input impedance of the circuit. It has a nominal value of 56 W for low voltage operation. Values up to 100 W may be used to increase the available transmit output voltage swing at the expense of lowvoltage operation. This internal voltage bias line must be connected to VL via an external resistor, RB, which dominates the ac input impedance of the circuit and should be 620 Ω for an 600 W input impedance or 910 Ω for a 900 Ω input impedance. The range of transmit and receive gain variations between short and long loops may be adjusted by connecting a resistor REX1 from this pin to Pin 3 (GND). This pin can be left open to set a.g.c. out of action. TELEFUNKEN Semiconductors Rev. A1, 06-May-96 U4055B/U4055B1 Pin Connection Figure 2. Absolute Maximum Ratings Reference point Pin 3, unless otherwise specified. Parameters Line current DC line voltage, tp = 3 ms Power dissipation, IL = 100 mA Junction temperature Ambient temperature range Storage temperature range Pin 13 Symbol IL VL Ptot Tj Tamb Tstg Value 200 20 560 150 –28 to + 80 –55 to +150 Unit mA V mW °C °C °C Symbol RthJA Value 85 Unit K/W Thermal Resistance Parameters Junction ambient TELEFUNKEN Semiconductors Rev. A1, 06-May-96 3 (10) Preliminary Information U4055B/U4055B1 Electrical Characteristics Reference point Pin 3, cable equivalent = I = 1 km, ∅ 0.5 mm, R’ = 184 Ω, C’ = 37 nF, f = 1300 Hz, 0 dBm = 775 mVrms, RDC = 56 Ω / 2 W, Tamb = 25°C, unless otherwise specified. Parameters Line voltage Transmit and sidetone Input resistance Gain Noise at line weighted psophometrically Sidetone reduction DTMF-Amplifier Input resistance DTMF Gain y Volume range d 5% Receiving amplifier Input resistance Gain Receiving noise at earphone weighted psophometrially Gain change when muted Output saturation threshold MUTE or MUTE-input MUTE-input current MUTE off input voltage MUTE on input voltage MUTE-input current MUTE off input voltage MUTE on input voltage Supply voltage Output voltage Test Conditions / Pins IL = 8 mA IL = 20 mA IL = 30 mA IL = 73 mA, see figure 4 see figure 5 Pin 7 - 8 IL = 30 mA = l = 5 km adjustable with RAGC IL = 30 to 73 mA ≅ l = 5 km to 0 km IL = 73 mA ≅ l = 0 km VMIC = 0 V IL 20 mA see figure 6 Pin 8 - 3 IL = 30 mA ≅ I = 5 km Rex1 = 0 adjustable with Rex1 IL = 31 mA to 78 mA = l = 5 km to 0 km y Min. 1.8 3.0 3.6 7.7 Typ. 2.1 3.3 Max. 2.6 3.6 4.5 9.7 Unit V V V V Ri Gs DGs 7 57 –7 10 59 13 61 –9 kΩ dB dB –70 –68 dBm no GSTA 10 15 20 dB RD GD DGD 8 9 –7 10 13 13 –9 kΩ dB dB V0 1 Ri GR –1 50 –3 –5 kΩ dB DGR –5 –6 –7 dB –80 –71 dBm VRMS see figure 4 Pin 12 - 3 RHH = 300 Ω, IL = 30 mA ≅ l = 5 km RHH = 300 Ω adjustable with RAGC, IL = 31 mA to 78 mA l = 5 km to 0 km IL = 78 mA = l = 0 km S2 = 0 IL 20 mA IL 20 mA y y Pin 9 = 0 V Pin 9 = 1.5 V y see figure 4 IL 20 mA MUTE or MUTE switched off switched on Pin 10 IL 20 mA MUTE or MUTE switched off switched on Pin 10 y Output current Symbol VL ni GRM V0 15 0.8 20 1 24 1.5 dB Vpp IM VMoff VM on IM VM off VM on 20 1.5 50 80 10 20 0.3 30 0.3 µA V V µA V V V+ 3 1.5 2.5 I+ 1 4 (10) Preliminary Information 2.9 6.1 V 3.1 V 30 µA mA TELEFUNKEN Semiconductors Rev. A1, 06-May-96 VRM : Receiving voltage when muted G R : Receiving gain at 0 km D GRM = 20 lg VR VL GR = 20 lg VR VRM U4055B/U4055B1 Figure 3. Receiving amplifier TELEFUNKEN Semiconductors Rev. A1, 06-May-96 5 (10) Preliminary Information U4055B/U4055B1 Figure 4. Line and supply voltage characteristics 6 (10) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 06-May-96 TELEFUNKEN Semiconductors Rev. A1, 06-May-96 Preliminary Information D GS = GS – GS5 VL GS = 20 log VMIC GS : Sending gain at 0 km GS5 : Sending gain at 5 km D GS Typical = – 7.5 dB Measurement point pin 13 U4055B/U4055B1 Figure 5. Transmitting amplification 7 (10) VL GD = 20 log VDTMF (dB Volume range x5 %) min VO = 850 mVrms U4055B/U4055B1 Figure 6. DTMF amplifier 8 (10) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 06-May-96 U4055B/U4055B1 Ordering Information Extended Type Number U4055B1 U4055B Package DIP16 DIP16 Remarks High level mute Low level mute Dimensions in mm TELEFUNKEN Semiconductors Rev. A1, 06-May-96 9 (10) Preliminary Information U4055B/U4055B1 Ozone Depleting Substances Policy Statement It is the policy of TEMIC TELEFUNKEN microelectronic GmbH to 1. Meet all present and future national and international statutory requirements. 2. Regularly and continuously improve the performance of our products, processes, distribution and operating systems with respect to their impact on the health and safety of our employees and the public, as well as their impact on the environment. It is particular concern to control or eliminate releases of those substances into the atmosphere which are known as ozone depleting substances ( ODSs). The Montreal Protocol ( 1987) and its London Amendments ( 1990) intend to severely restrict the use of ODSs and forbid their use within the next ten years. Various national and international initiatives are pressing for an earlier ban on these substances. TEMIC TELEFUNKEN microelectronic GmbH semiconductor division has been able to use its policy of continuous improvements to eliminate the use of ODSs listed in the following documents. 1. Annex A, B and list of transitional substances of the Montreal Protocol and the London Amendments respectively 2 . Class I and II ozone depleting substances in the Clean Air Act Amendments of 1990 by the Environmental Protection Agency ( EPA) in the USA 3. Council Decision 88/540/EEC and 91/690/EEC Annex A, B and C ( transitional substances ) respectively. TEMIC can certify that our semiconductors are not manufactured with ozone depleting substances and do not contain such substances. We reserve the right to make changes to improve technical design and may do so without further notice. Parameters can vary in different applications. All operating parameters must be validated for each customer application by the customer. Should the buyer use TEMIC products for any unintended or unauthorized application, the buyer shall indemnify TEMIC against all claims, costs, damages, and expenses, arising out of, directly or indirectly, any claim of personal damage, injury or death associated with such unintended or unauthorized use. TEMIC TELEFUNKEN microelectronic GmbH, P.O.B. 3535, D-74025 Heilbronn, Germany Telephone: 49 ( 0 ) 7131 67 2831, Fax number: 49 ( 0 ) 7131 67 2423 10 (10) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 06-May-96