AN618 Panasonic Semiconductor, AN618 Datasheet

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ICs for Telephone AN6175K Hands-free Speech Network IC Overview The AN6175K is a speech network IC incorporating a hands-free function. It provides for a high-quality hands- free telephone or handset telephone. The hands-free telephone function(HF)includes : • MIC amplifier capable ...

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AN6175K Block Diagram 2 ICs for Telephone ...

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ICs for Telephone Pin Descriptions Pin No. Symbol Description MAO 1 MIC amp. output (hands-free mode) (HF) MAI 2 MIC amp. input (hands-free mode) (HF) MAI 3 MIC amp. input (handset mode) (HS) MAO 4 MIC amp. output (handset mode) ...

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AN6175K Electrical Characteristics (Ta= Parameter HS power supply HS mode line voltage (1) HS mode line voltage (2) HS mode V 2 voltage ( mode V 2 voltage ( mode V 1 voltage (1) ...

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ICs for Telephone Electrical Characteristics (cont.) (Ta= Parameter HF transmitter Trans. gain (1) Trans. gain (2) Trans. noise Trans. att. gain (1) Trans. att. gain range (1) Trans. att. idling gain (1) Trans. att. gain (2) Trans. att. ...

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AN6175K Electrical Characteristics (Design Values for Reference) (cont.) (Ta= Parameter HF power supply HF mode internal reference voltage (1) HF mode internal reference voltage (2) HF mode internal reference voltage (3) HF mode AC impedance Control voltage Low ...

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ICs for Telephone Operation in the Hand-free Mode Block Diagram MIC MIC Level Noise Level TLOG1 Monitor Monitor SP Level RLOG1 Monitor SP Attenuator Control Input signal C1 C2 Trans. noise ...

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AN6175K 1.Setting (1) Setting the Line Path 1—1 Setting the DC Characteristics The AN6175K can be made compatible with local telephone regulations by setting the following characteristics : 1. Gradient of the I —V characteristics Degree of ...

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ICs for Telephone 2. Setting the degree of shifting of the I — Referring to Figs.1—1 and 1—3, the resistance of R33 is now set to 820 (standard). • If R33's resistance is decreased, the curve ...

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AN6175K 2. Automatic PAD control adjustment Automatic PAD control, or APC, is such a function as to automatically adjust transmission gain according to line current (I The gain range of the APC of the AN6175K is 6 dB. The adjustment ...

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ICs for Telephone MIC Preamplifier Gain/Frequency Characteristics Adjustment The external components, R12, R13, C6, and C45, determine the MIC preamplifier gain/frequency characteristics in the HS mode as shown in Fig. 2—2. R12 and C6 form a low-pass filter, and R13 ...

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AN6175K 2–2 Setting the Receiver System The block diagram of the receiver system in the HS mode is shown below. BN C32 Vr C31 R32 30 RPI Receiver preamplifier Fig.2–4 HS Mode Receiver System Block Diagram There are two adjustments ...

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ICs for Telephone 2. Receiver Amplifier Gain Adjustment Use R26, R27, and C21 to adjust the receiver amplifier gain as shown in Fig.2–7. Handset receiver C22 R27 R26 Receiver amplifier AN6175K Fig.2–7 Receiver Amplifier (3) Hands-Free ...

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AN6175K 3–2 Setting the Receiver System The block diagram of the receiver system in the HF mode is shown below. BN C32 Vr R31 C31 R32 RPI 30 Fig.3–2 HF Mode Receiver System Block Diagram There are two settings for ...

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ICs for Telephone Detailed Pin Descriptions Pin No. Symbol 1 MAO(HF) 2 MAI(HF) 3 MAI(HS) 4 MAO(HS) 5 TND Description [MIC preamplifier output in the HF mode] Amplified HF mode transmitter signals are output from this pin through C7(0.1 F)and ...

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AN6175K Detailed Pin Descriptions(cont.) Symbol Pin No. 6 TVR 7 TLI1 8 TLI2 9 RLI1 10 RLI2 11 TLO1 16 Description [Noise detecting circuit reference] This pin must be grounded through C8 (22 F). [LOG amp.(1)input(from MIC amp. out- put)] ...

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ICs for Telephone Detailed Pin Descriptions(cont.) Pin No. Symbol 12 TLO2 [LOG amp.(3)output] Outputs the amplified receiver preamp. 13 RLO1 output. Grounded through C15(2.2 The attack recovery time of the attenuator changes with the capacitance of C15. [LOG amp.(4)output] Outputs ...

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AN6175K Detailed Pin Descriptions(cont.) Symbol Pin No. [Transmitter mode)] The transmitter attenuator outputs trans- 18 TAO mitter signals in the HF mode from this pin to Pin36 through C37(0.1 F). The output impedance, Zout [Receiver att. output(hands-free mode)] ...

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ICs for Telephone Detailed Pin Descriptions(cont.) Pin No. Symbol [Loudspeaker amp.(2)output] Pins24 and 25 form a BTL configuration. The output impedance, Zout= SPO2 [Loudspeaker amp.(1)output] Pins24 and 25 form a BTL configuration. Connects through R18 and C12 to ...

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AN6175K Detailed Pin Descriptions(cont.) Pin No. Symbol 31 HS, HF/MF [Mode switching(handset/hands-free)] This pin must be connected HS/HF the HS mode (SW1 to a GND for the HF mode (SW1 to b). [Reference for the ...

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ICs for Telephone Detailed Pin Descriptions(cont.) Pin No. Symbol 38 TRB [To the emitter of the transmission transistor] This pin connects to the emitter TRE (transmission transistor)and R33 to adjust the Q3 gain. [Band-gap ref. voltage output] ...