U4082B-DEV-BOARD Atmel, U4082B-DEV-BOARD Datasheet
U4082B-DEV-BOARD
Related parts for U4082B-DEV-BOARD
U4082B-DEV-BOARD Summary of contents
Page 1
... Fast Channel Switching Allows Quasi-duplex Operation • Proper Operation in Noisy Surroundings 1. Description The low-voltage voice-switched speakerphone circuit, U4082B, incorporates a wide range of functions. The versatility of the device is further enhanced by giving access to internal circuit points. The block diagram (see detectors, transmit and receive attenuators operating in complementary functions, background noise monitors, chip disable, dial tone detector and mute function ...
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... Figure 1-2. Block Diagram with External Circuit U4082B 2 4743D–CORD–03/06 ...
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... TLO1 6 23 HTO- TLI1 7 22 RECO HTI RLI2 10 19 MICO RLO2 11 18 MIC TLO2 12 17 TLI2 MUTE 13 16 CPT VCI the receive attenuator is at maximum gain when in receive mode the receive gain is down 35 dB. It does not affect the transmit mode B U4082B ...
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... The U4082B provides the necessary level detectors, attenuators, and switching control for a properly operating speakerphone. The detection sensitivity and timing are externally controlla- ble ...
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... Their purpose is to control the transmit and “Electrical Characteristics” on page Attenuator Input the circuit is in receive mode –240 mV with respect voltage (with respect the most direct T B 7-3 and 7-4 on page 18 for their DC and AC U4082B Figure 14. , the circuit ...
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... Signal input The 36 mV offset at the comparator's input keeps the comparator from changing state unless the speech level exceeds the background noise by approximately 4.0 dB. The time constant of the external RC (approximately 4.7s) determines the response time to background noise variations. U4082B 6 8. (Figure 3-2) ...
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... +6.0 dB, and attenuator transmit gain When VCI < the attenuator receive gain 8). 3-3). If the circuit is in idle mode, and the incoming To attenuator control C4 is controlled, preventing possible erratic S U4082B . It affects the which in turn T Figure 7 ...
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... Idle” means speech has ceased in both transmit and receive paths. The attenuators are then slowly switched (1s) to idle mode. • Switching to full transmit or receive mode from any other mode is at the fast rate ( U4082B 8 Mode Selection Table Inputs ...
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... A diagram of the C circuitry is shown in Figure T C Attenuator Control Block Circuit µA (Figure 1-2 on page 2), if there is a sufficient signal at 3-4, and operates as follows attenuators + 4 Attenuator control Volume control Dial tone detector AGC U4082B 9 ...
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... The open loop gain is typically < 100 Hz), and the gain-bandwidth is typically 1.0 MHz (see Figure 7-7 on page an output impedance of < 10 until current limiting is reached (typically 1.5 mA). Input bias cur- rent at MIC is typically –40 nA. Figure 3-5. U4082B 10 is typically 120 k , and C is typically 5.0 µ ...
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... Filter The operation of the filter circuit is determined by the external components. The circuit within the U4082B from pins buffer with a high input impedance (> and a low output impedance (< The configuration of the external components determines whether the cir- cuit is a high-pass filter (as shown in filter ...
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... Figure 3-6. Figure 3-7. U4082B 12 High-pass Filter 220 4700 4700 pF 2 305Hz for C - Low-pass Filter V 220 k B 0.01 µ 0.001 µ for - 300 260 µ 4.0 20 kHz f N 4743D–CORD–03/06 ...
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... Figure 7-10 on page , forms a low-pass filter for power supply B (see Figure 7-8 on page S Value –1.0 to +7.0 –1 1.0) S –1 0.5) S –0 0.5) S –55 to +150 125 –20 to +60 520 120 U4082B “AGC” on 20), Figure 8 Unit K/W 13 ...
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... Receive attenuator gain Gain change AGC gain change Idle mode Range mode Volume control range RECO DC voltage RECO DC voltage RECO high voltage RECO low voltage RI input resistance U4082B 14 Test Conditions Pin 4 Pin 3 Pin 12 Pin 15 Pin 13 Pins RECO, TO; pins MICO; pin 10 At HTO–, HTO+; pins 6, 5 ...
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... MICO –50.0 0.0 +50 70.0 80.0 VOLM GBW 1 3.7 MICOH V 200.0 MICOL I –40 –55.0 G –68.0 R 50.0 90.0 MUTE V 2.0 MUTEH V 0.0 MUTEL THD 0. –20.0 0.0 +20.0 VOS HB –30.0 0.0 +30.0 VOS G 60.0 80.0 VOLH GB 1.0 U4082B Unit µA µA µA 3 MHz 0 MHz 15 ...
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... Sink current CPR, CPT output resistance CPR, CPT leakage current Filter Voltage offset sink current FI bias current System Distortion R Mode T Mode Figure 6-1. Hybrid Amplifier Distortion Test 0.1 µF I U4082B 16 Test Conditions HTO– to HTO+ at HTI I = –5 +5 –5 +5 300 Hz < f < 10 kHz ...
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... Attenuator Gain versus VCT (Pin 14 -10 T attenuator -20 -30 -40 -50 -320 -160 V CT U4082B Typical Change – +60 C –0.3%/ C –0.4%/ C +0.8%/ C 0.0008 dB/ C 0.004 dB/ C +0.6%/ C +20.0 mV/ C –0.15%/ C ±4.0 mV/ C ±0.02%/ C –10.0 nA/ C 0.001 attenuator 0 160 ...
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... Figure 7-2. Figure 7-3. Figure 7-4. U4082B 18 Level Detector DC Transfer Characteristics 500 400 300 200 100 0 0 -20 -40 I Level Detector AC Transfer Characteristics 300 0.1 µF 250 200 0.047 µF or 0.1 µF 150 kHz 100 (mVrms) i Level Detector AC Transfer Characteristics versus Frequency ...
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... Receive Attenuation Gain versus -10 -20 -30 -40 2.8 st -hybrid Amplifier Open-loop Gain and Phase versus Frequency Microphone amp. phase Hybrid amp. phase (kHz) Receive mode Minimum recommended level 1.2 0.5 0.7 0.9 VCI 3.2 3.4 3.6 V (V) S 120 100 100 1000 U4082B 19 ...
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... Figure 7-8. Figure 7-9. Figure 7-10. V U4082B 20 Input Characteristics at CD, MUTE 120 100 Valid for 0 CD, MUTE Input Voltage (V) Supply Current versus Supply Voltage Output Characteristics B 3.0 2 2.0 1 3.5V S 1.0 0 0.5 1.0 -I (mA) (Load Current 6 0. (V) S 1.5 2.0 2.5 4743D–CORD–03/06 ...
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... Figure 7-11 Design Guidelines 8.1 Switching Time The switching time of the U4082B circuit is determined primarily by C 3-3 on page TLO1, TLO2). For more information, please refer to The time to switch from idle to receive or transmit mode is determined by the capacitor at C together with the internal current sources. The switching time is: ...
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... G HT network (measured at 0.4V/V, or –8 dB) Figure 8-1. U4082B 22 6, the rise time of the level detectors' outputs to new speech is quick by comparison where coupling capacitors are omitted for the sake of simplicity: is the gain of the microphone amplifier measured from the microphone output the gain of hybrid amplifiers, measured from TO to the HTO– ...
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... RI to RECO is the gain of the speaker amplifier, measured from RECO to the differential output of the is the acoustic coupling, measured from the speaker differential voltage to the S MICO HTO -, HTO + TO (V) S Hybrid amp. TO HTO-/HTO TLI1 - Comparator + RLI1 U4082B HIT Tip Hybrid Ring Filter 23 ...
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... Loop Gain The total loop gain (of circuit. This can be expressed as Using the typical numbers mentioned above, and knowing that G acoustic coupling can be determined: G < –[31 + 20.1 + (–15 (–40) + 26.8] = –22.9 dB U4082B 24 (Figure 7-7 on page 19). For the circuit in dBm/10 10 0.6 ------------------------------------- - ( the speaker impedance, and the dBm term is the incoming signal level increased by ...
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... ------ - ------------------------------------------------- - need to be determined. Referring to 3 will flow through R 3 (4) is obtained from one side of that 3 (6) occurs when the receive attenuator (7) need to be determined. With sound applied to the defined by (10) U4082B Figure 8-3 on into RLI2 combin into TLI1 ...
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... In some cases the coupling signal will add, and other times subtract from the incoming signal. The physical design of the speakerphone enclosure, as well as the specific phone line to which it is connected, will affect the acoustic and side tone couplings, respectively. • The M found from the following equation: G AC(MAX) U4082B 26 ( 0.0019 × (11 ...
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... RI, the threshold can be increased. The resistor value is calculated from – ------------------- - 1 – –37 dB. Experience has shown, how- AC(MAX) ) allowed in the system equation 14 yields a maximum side tone -R ratio, and equation 10 can be used to determine each represent the combined impedance of the 1 4 U4082B ST (see Fig ...
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... Transmit/Receive Detection Priority Although the U4082B was designed to have idle mode such that the attenuators are halfway between their full on and full off positions, idle mode can be biased towards the transmit or the receive side. With this done, gaining control of the circuit from idle will be easier for that side towards which it is biased since that path will have less attenuation at idle ...
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... Extended Type Number U4082B-MFLG U4082B-MFLG3G 11. Package Information Package SO28 Dimensions in mm 0.4 1. 4743D–CORD–03/06 Package Remarks SO28 Tube, Pb-free SO28 Taped and reeled, Pb-free 18.05 17.80 0.25 0.10 16. 9.15 8.65 7.5 7.3 2.35 10.50 10.20 technical drawings according to DIN specifications U4082B 0.25 29 ...
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