TS34118CS28C8 TSC [Taiwan Semiconductor Company, Ltd], TS34118CS28C8 Datasheet
TS34118CS28C8
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TS34118CS28C8 Summary of contents
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SOP-28 DIP-28 General Description The TS34118 Voice Switched Speakerphone Circuit incorporates the necessary amplifiers, attenuators, level detectors, and control algorithm to form the heart of a high quality hands-free speakerphone system. Included are a microphone amplifier with adjustable gain and ...
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Recommended Operating Conditions Description Supply voltage (pin 4) (see Text) CD input (pin 3), MUT input (pin 12) I current (pin 15) VB VLC (pin 13) Attenuator input signal voltage (pin 9,21) Microphone amplifier, Hybrid amplifier gain Load current @RXO, ...
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Electrical Characteristics - Parameter Attenuators-continued (T =+25ºC) A TXI input resistance (TXI<350mVrms) Gain tracking ( Tx, Idle, Rx Attenuator Control (T =+25º voltage (pin 14 model ( dle ...
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Electrical Characteristics - Parameter Filter (T =+25ºC) A Voltage offset 220KΩ from sink current FI bias current System Distortion (T =+25ºC, f=1.0KHz mode (from FI to RXO, FO connected ...
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Pin Function Description Pin Name 1 FO Filter output. Output impedance is less than 50 ohms Filter input. Input impedance is greater than 1.0Mohm. Chip Disable. A logic low(<0.8V) sets normal operation. A logic high (>2.0V) disables the ...
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Typical Application Circuit Voice Switched Speakerphone Circuit Figure 1. Hybrid Amplifier Distortion Test Figure 2. TS34118 Block Diagram 6/23 TS34118 Version: A08 ...
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Introduction The fundamental difference between the operation of a speakerphone and a handset is that of half-duplex versus full duplex. The handset is full duplex since con-version can occur in both directions (transmit and receive) simultaneously. A speakerphone has higher ...
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Attenuators The attenuators are controlled by the single output of the Control Block, which is measurable at the CT pin (pin 14). When the CT pin is at +240 millivolts with respect to VB, the circuit is in the receive ...
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Background Noise Monitors The purpose of the background noise monitors is to distinguish speech (which consists of bursts) from background noise (a relatively constant signal level). There are two background noise monitors-one for the receive path and one for the ...
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Attenuator Control Block The Attenuator Control Block has the seven inputs described above: -The output of the comparator operated by RLO2 and TLO2 (microphone/speaker side) - designated C1. -The output of the comparator operated by RLO1 and TLO1 (TIP/Ring side) ...
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Attenuator Control Block - Continue 4) The circuit will switch to the slow idle mode when a) both talkers are quiet (no speech present when one talker’s speech level is continuously overridden by noise at the other speaker’s ...
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Microphone Amplifier – Continue Hybrid Amplifiers The two hybrid amplifiers (at HTO+, HTO-, and HTI), in conjunction with an external transformer, provide the two-to four wire converter for interfacing to the telephone line. The gain of the first amplifier (HTI ...
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Filter – Continue As a low pass filter (Figure 9), it can be used to roll off the high end frequencies in the receive circuit, which aids in protecting against acoustic feedback problems. With an appropriate choice of an input ...
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Switching Time - Continue If the circuit is switching to “slow idle”, the time constant is determined by the CT capacitor and RT, the external resistor (see Figure 6). With CT = 5.0µF, and RT = 120KΩ, the time constant ...
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Design Equations - Continue 2. To provide a reasonable signal level to the TLI2 level detector; and 3)to minimize any gain applied to broadband noise generated within the attenuator. However, to cover the normal voice band, the microphone amplifier’s gain ...
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Design Equations - Continue Figure 10. Basic Block Diagram For Design Purpose This is the general equation defining the microphone voltage necessary to switch comparator C1 when a received signal VL is present. The highest VM occurs when the receive ...
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Design Equations - Continue The “M” terms are the slopes of the lines (0.52,0.024, and 0.0019) which are the coefficients of the three equations. The MRX line represents the receive to transmit threshold in that it defines the microphone signal ...
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Application Information Dial Tone Detector The threshold for the dial tone detector is internally set at 15mV (10mVrms) below VB (see Figure 5). That threshold can be reduced by connecting a resistor from RXI to ground. The resistor value is ...
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Application Information - Continue Volume Control If a potentiometer with a standard linear taper is used for the volume control, In situations where this may be objectionable, a potentiometer with an audio taper (commonly used in radio volume controls) will ...
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Marking Diagram Voice Switched Speakerphone Circuit SOP-28 Mechanical Drawing Y = Year Code M = Month Code (A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep, J=Oct, K=Nov, L=Dec Lot Code 20/23 TS34118 SOP-28 DIMENSION MILLIMETERS INCHES DIM ...
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Marking Diagram Voice Switched Speakerphone Circuit DIP-28 Mechanical Drawing Y = Year Code M = Month Code (A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep, J=Oct, K=Nov, L=Dec Lot Code 21/23 TS34118 DIP-28 DIMENSION MILLIMETERS INCHES DIM ...
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Specifications of the products displayed herein are subject to change without notice. TSC or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies. Information contained herein is intended to provide a product description only. No ...
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Voice Switched Speakerphone Circuit 23/23 TS34118 Version: A08 ...