U4084B TEMIC [TEMIC Semiconductors], U4084B Datasheet
U4084B
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U4084B Summary of contents
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... Low-Voltage, Voice-Switched Circuit for Hands-Free Operation Description The low-voltage, voice-switched speakerphone circuit U4084B incorporates the features listed below. The ver- satility of the device is further enhanced by giving access to internal circuit points. The block diagram shows amplifiers, level detectors, transmit and receive attenuators operating in comple- ...
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... Preliminary Information attenuator V S AGC Background- noise monitor Attenuator control Dial tone detector + – attenuator RLI2 RECO RI VCI Figure 1. Block diagram 24 CPR 20 TLI1 22 Level RLO1 detectors 22 TLO1 U4084B 23 12626 RLI1 TELEFUNKEN Semiconductors Rev. A1, 31-Jan-97 ...
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... Figure 2. Block diagram with external circuit TELEFUNKEN Semiconductors Rev. A1, 31-Jan-97 Preliminary Information U4084B 3 (26) ...
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... U4084B Pin Description Pin Symbol Function 1 GND Ground 2 NC Not connected 3 CD Chip disable. A logic LOW (< 0.8 V) sets normal operation. A logic HIGH (> 2.0 V) disables the IC to conserve power. The input impedance is nominally Supply voltage 2 approximately @ 4 mA. The AGC circuit reduces the receive attenuator gain @ 25 dB ...
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... R thJA R thJA Symbol Min. Pin 4 V 3.5 S Pin3 0 Pin 9 Pin 12 I – B Pin 10 VCI 0 Pins 6 and Pin –20 amb U4084B Value Unit 125 C C 650 mW 520 Value Unit 100 K/W 120 K/W Typ. Max. Unit – 6.5 V – ...
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... U4084B Electrical Characteristics + 5 0.8 V, unless otherwise specified amb S Parameters Test Conditions / Pins Power supply Supply current input resistance input voltage – High – Low Output voltage Output resistance ...
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... 3.7 S MICOH V MICOL 2 –55.0 MUTE 50.0 MUTE V 2.0 MUTEH V 0.0 MUTEL THD LSO I LSK CPLK U4084B Typ. Max. Unit 240.0 0.0 mV –240.0 m –60.0 –40 60 2.0 3.6 k –60.0 nA 15.0 20.0 mV 0.0 +50.0 mV 80.0 dB 1.0 MHz V 200.0 mV –40 –68 ...
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... U4084B Temperature Characteristics Parameter Supply current 0 Supply current 2 output voltage 5 Attenuator gain (max. gain) Attenuator gain (max. attenuation) Attenuator input resistance (@ TI, RI) Dial-tone detector threshold CT source, sink current Microphone, hybrid offset Transmit receive switching threshold ...
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... The U4084B provides the level detectors, attenuators, and switching control necessary for proper operation of the speakerphone. The detection sensitivity and timing are externally controllable. Additionally, the U4084B ...
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... U4084B Level Detectors, Figure 4 There are four level detectors, two on the receive side and two on the transmit side. As shown in figure 4, the terms in parentheses form one system, and the other terms form the second system. Each level detector is a high-gain amplifier with back-to-back diodes in the feedback path, resulting in a non-linear gain which permits operation over a wide dynamic range of speech levels ...
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... TLO1 (Tip/Ring side) – designated C2 D The output of the transmit background-noise monitor – designated C3 D The output of the receive background-noise monitor – designated C4 D The volume control D The dial-tone detector D The AGC circuit U4084B to R attenuator to attenuator C4 control 12674 S is controlled, preventing S 11 (26) ...
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... U4084B The single output of the control block controls the two attenuators. The effect of C1– follows: Inputs don’t care and C4 are not both 0. ...
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... The input bias current at MIC is typically W – MIC from Mike 9 MUTE Figure 7. Microphone amplifier and mute U4084B C1 ... C4 12675 , while the inverting in- B – with an out until current limiting is reached – MICO V ...
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... U4084B When activated, the muting function (Pin 9) reduces the gain of the amplifier to approximately – (with RMI shorting the output to the inverting input (see figure 7). The mute input has a threshold of approximately 1.5 V, and the voltage at this pin must be kept within the range of ground and V S the mute function is not used, the pin should be grounded ...
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... Figure 13. Receive attenuation gain versus V 120 100 0.9 1 7871 e Figure 14. Microphone amplifier open loop gain and phase U4084B 3 3.2 3.4 3 120 100 Gain 20 0 1000 1 10 100 f ( kHz ) versus frequency ...
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... U4084B 120 100 v v Valid for 0 CD, MUTE 7774 e Input Voltage (V) Figure 15. Input characteristics @ CD, MUTE 7880 e S Figure 16. Supply current versus supply voltage 16 (26) Preliminary Information 3.0 2.5 2.0 1.5 1.0 0 6.5 0 0.5 93 7776 e Figure 17 ...
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... Design Hints Switching Time, Figure 6 The switching time of the U4084B circuit is determined (Pin 11, refer to figure 6), and the capacitors at the level-detector outputs (RLO1, RLO2, TLO1, TLO2), see figure 2. The switching time from idle to receive or transmit mode is determined by the capacitor together with the T internal current sources ...
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... U4084B 60 MICO 1000 220 7870 kHz ) Figure 19. Power supply rejection of the microphone amplifier MIC amp. MICO – + Acoustic coupling + – RLI2 SAO Speaker amp. Figure 21. Basic block diagram for design purposes 18 (26) Preliminary Information ...
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... T threshold. The M I defines the threshold level on one side (transmit or receive) necessary to overcome noise on the other occurs when the and I need 12678 Figure 22. Switching thresholds U4084B G EXT ...
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... Transmit/Receive Detection Priority Although the U4084B was designed to have an idle mode such that the attenuators are halfway between their full-on and full-off positions, the idle mode can be biased towards the transmit or the receive side ...
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... Applications TELEFUNKEN Semiconductors Rev. A1, 31-Jan-97 Preliminary Information U4084B 21 (26) ...
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... U4084B 22 (26) Preliminary Information TELEFUNKEN Semiconductors Rev. A1, 31-Jan-97 ...
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... TELEFUNKEN Semiconductors Rev. A1, 31-Jan-97 Preliminary Information U4084B 23 (26) ...
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... U4084B 0.05 F 36k 300k 1.5M 12682 24 (26) Preliminary Information 0.05 F 0.1 F 5.1k 6. 0 U4084B 0.1 F 0.1 F 220pF 180k 0.1 F 5.1k 300k 220 F 120k 620 0.2 F 5.1k 0.02 F TELEFUNKEN Semiconductors Rev. A1, 31-Jan-97 ...
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... Package Information Package DIP24 (CEI) Dimensions Package SO24 Dimensions in mm 15.55 15.30 0.4 1.27 13. TELEFUNKEN Semiconductors Rev. A1, 31-Jan-97 Preliminary Information 32.26 31.24 4.06 3.56 3.81 3.18 1.65 0.58 2.54 1.02 0.38 27. 2.35 0.25 0.10 13 technical drawings according to DIN specifications 12 U4084B 15.49 14.99 0.89 13.97 0.38 12.70 0.38 17.02 0.20 15.24 technical drawings according to DIN specifications 13041 9.15 8.65 7.5 7.3 0.25 10.50 10.20 13037 25 (26) ...
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... U4084B 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 ...