MC33218ADWR2 Freescale Semiconductor, MC33218ADWR2 Datasheet

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... Freescale Semiconductor, Inc. Advance Information Voice Switched Speakerphone with Microprocessor Interface The Motorola MC33218A 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 mute, transmit and receive attenuators, a background monitoring system for both the transmit and receive paths, and level detectors for each path ...

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... Freescale Semiconductor, Inc. MAXIMUM RATINGS Rating Supply Voltage Any Input Maximum Junction Temperature Storage Temperature Range NOTE: Devices should not be operated at or outside these values. The “Recommended Operating Limits” provide for actual device operation. RECOMMENDED OPERATING LIMITS Characteristic Supply Voltage (Non–AGC Range) ...

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... Freescale Semiconductor, Inc. ELECTRICAL CHARACTERISTICS (continued) Characteristic ATTENUATORS Receive Attenuator Gain (f = 1.0 kHz, Maximum Volume) Full Attenuation Range ( Mode T x Mode Idle Mode Range ( Mode) Half Attenuation Range ( Mode T x Mode Idle Mode Range ( Mode) Volume Control Range (R x Mode Only, B3–B0 Changed from 0000 to 1111, See Figures 6, 7) ...

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... Freescale Semiconductor, Inc. ELECTRICAL CHARACTERISTICS (continued) Characteristic MUTING ( Gain) Timing from Data Ready Lo–to–Hi (See Figure 27) To Mute To Enable RECEIVE AMPLIFIER (Pins 15, 16) Output Offset with Respect ( Input Bias Current (Pin 16) Open Loop Gain (f < 100 Hz) Gain Bandwidth Maximum Output Voltage Swing (Note 2) ...

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... Freescale Semiconductor, Inc. ELECTRICAL CHARACTERISTICS (continued) Characteristic SERIAL PORT (Pins 17–19) Switching Threshold Clock Input Current (Pin 17 5.0 V Data Input Current (Pin 18 0 5.0 V Data Ready Input Current (Pin 19 0 5.0 V Timing (Minimum Requirements) (See Figure 2) Data Ready Falling Edge to Clock ...

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... Freescale Semiconductor, Inc. TYPICAL TEMPERATURE PERFORMANCE Characteristics Power Supply Current Enabled Open Disabled Open V B Output Voltage ( Source Current (Switching Mode Sink Current (Switching Mode) Attenuator “On” Gain (Full Range) Attenuator Range (Full Range) Volume Control Range (R x Mode Only, B3–B0 ...

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... Freescale Semiconductor, Inc. Data Ready t 1 Clock Data NOTES: 1. Maximum clock and data rate is 1.0 MHz. There is no required minimum rate entered first, B0 last. 3. Data is entered on the clock rising edge. 4. Clock can continue to toggle after B0 is entered if Data Ready goes high before the clock’s next rising edge. ...

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... Freescale Semiconductor, Inc. Figure 3. MC33218A Block Diagram and Test Circuit From Microphone 0.22 300 k 3.0 k MCO 22 21 MCI V B Microprocessor Data DIN 18 Register Data CK and 17 Decode Clock Logic POR 20 SPI 0.1 Disable 8 Normal CD Bias 100 13 GND 47 100 MC34119 Speaker Amplifier NOTES: 1. All capacitors are in F unless otherwise noted. ...

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... Freescale Semiconductor, Inc. Figure 4. Attenuator Gain versus V CT (Pin 7) (Full Attenuator Range) 10 Transmit Receive Attenuator Attenuator 0 –10 – 20 – 30 – 40 – 50 –100 50 – – (mV) Figure 6. Receive Gain versus Volume Control Levels (Full Attenuation Range 3.5 V – 3.1 V – 20 – 2.7 V – 40 – ...

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... Freescale Semiconductor, Inc. Figure 10. Level Detector AC Transfer Characteristics versus Frequency 100 100 mVrms 60 TLI RLI 20 XDI 5.1 k 500 0 C 0 – 1.0 kHz 100 300 1 FREQUENCY (Hz) Figure 12. CD Input Characteristics (Pin Valid for 1.0 2.0 3.0 4.0 INPUT VOLTAGE (V) Figure 14 Output Characteristics 4 ...

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... Freescale Semiconductor, Inc. Figure 16. Receive Amp and Microphone Amp Output Swing 1.0 THD = 5% 0.5 THD 1% THD measured at TAO, RAO 0 2.5 3.5 4 (V) Figure 18. Serial Port Input Characteristics (Pins 17, 18, 19) 300 200 Clk (DR = Hi) 100 Valid for 1.0 2.0 3.0 4.0 0 INPUT VOLTAGE (V) ...

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... Freescale Semiconductor, Inc. Figure 21. Idle 200 mVrms, 1.0 kHz Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î Î MCO Î Î Î Î Î Î Î Î Î Î Î Î Î ...

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... Freescale Semiconductor, Inc. Figure 23. Transmit 200 mVrms, 1.0 kHz Î Î Î Î Î Î Î Î Î MCO Î Î Î Î Î Î Î Î Î 300 ms Î Î Î RXO Î Î Î 200 mV TLO RLO Idle T x Î Î Î Î Î Î Î ...

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... Freescale Semiconductor, Inc. Figure 24. Transmit 200 mVrms, 1.0 kHz Î Î Î Î Î Î Î Î Î Î MCO Î Î Î Î Î Î Î Î Î Î 1.0 s Î Î Î Î RXO 200 mV TLO RLO Idle 250 mV ...

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... Freescale Semiconductor, Inc. Figure 25. Transmit 200 mVrms, 1.0 kHz Î Î Î Î Î Î Î Î Î Î MCO Î Î Î Î Î Î Î Î Î Î 1.0 s Î Î Î Î RXO 200 mV TLO RLO Idle 250 mV ...

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... Freescale Semiconductor, Inc. CD Input (Pin 8) 5.0 s Î Î Î Î Î Output at RAO, TAO Î Î Î Î Î NOTE: Enable time t1 depends on the length of t off according to the following chart: t off Data Ready (Pin 19) Î Î Î Î Î Î ...

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... Freescale Semiconductor, Inc. Introduction The fundamental difference between the operation of a speakerphone and a telephone handset is that of half–duplex versus full–duplex. The handset is full duplex, meaning conversation can occur in both directions (transmit and receive) simultaneously. This is possible due to both the low ...

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... Freescale Semiconductor, Inc. MC33218A Voltage Clamps Referring to Figure 3, the outputs of the two level detectors drive the comparator. The comparator’s output state – depends on whether the transmit or receive speech signal is stronger, as sensed by the level detectors. The Attenuator Control Circuit uses this signal, along with the background noise monitors, to determine which mode to set ...

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... Freescale Semiconductor, Inc Signal 500 Input XDI V B (RLI) 2.0 A External Component Values are Application Dependent. Microprocessor Interface The three line SPI port (Pins 17–19) is used for setting various functions with a single 8 bit word. The functions are as follows: – Volume Control: Bits B0–B3 control the gain of the attenuators only when in the receive mode. Setting B3– ...

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... Freescale Semiconductor, Inc. If POR is driven by an external logic output, its input current requirement is shown in Figure 19. Figure 33. Power On Reset Pin 5.0 k POR Microphone Amplifier, Mute The microphone amplifier (Pins 21, 22) has the non–inverting input internally connected while the inverting input and the output are pinned out. Unlike most op– ...

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... Freescale Semiconductor, Inc. Switching and Response Time Theory The switching time of the MC33218A circuit is dominated by the components (Pin 7, refer to Figure 3), and second by the capacitors at the level detector outputs (RLO, TLO). The transition time to receive or to transmit mode from idle, or from the other mode, is determined by the capacitor together with the internal current sources (refer to Figure 29) ...

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... Freescale Semiconductor, Inc. experience has shown “comfortable response“ by the circuit. 2) The distortion in the receive attenuator will increase as the CT capacitor value is decreased. The extra THD will be most noticeable at the lower frequencies, and at the lower amplitudes. Table 1 provides a guideline for this issue. ...

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... Freescale Semiconductor, Inc. (the switchpoint occurs when This has to be the last step as the resistor values depend on all of the above adjustments, which are based on the mechanical, as well as the electrical, characteristics of the system. NOTE: An extreme case of level detector misadjustment can result in “motorboating”. In this condition, with a receive signal applied, sound from the speaker enters the microphone, and causes the circuit to switch to the transmit mode ...

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... Freescale Semiconductor, Inc. Upon powering up the MC33218A, or when the IC is disabled by means of the CD pin (Pin 8), the eight registers are internally set to a logic 0, regardless of their previous contents. This default condition corresponds to normal voice switched operation attenuator range, active microphone amplifier, and maximum receive volume level. ...

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... Freescale Semiconductor, Inc. Board Layout, RFI Interference Although the MC33218A is meant to be used at audio frequencies, the various amplifiers within have bandwidths exceeding 1.0 MHz, and can therefore oscillate due to stray capacitance and other parasitics if care is not taken in the board layout board, with a ground plane, is recommended for breadboarding as well as production ...

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... Freescale Semiconductor, Inc – mag nit communication signal, usually expressed in dB. Bandwidth – The range of information carrying frequencies of a communication system. Battery – The voltage which provides the loop current to the telephone from the CO. The name derives from the fact that COs have always used batteries, in conjunction with AC power, to provide this voltage. C– ...

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... Freescale Semiconductor, Inc. Return Loss – Expressed in dB measure of how well the telephone’s AC impedance matches the line’s AC characteristic impedance. With a perfect match, there is no reflected signal, and therefore infinite return loss calculated from LINE * RL 20 log (Z LINE Ring – One of the two wires connecting the central office to a telephone ...

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... Freescale Semiconductor, Inc. –A– –T– SEATING PLANE 0.25 (0.010) –A– 24X 0.010 (0.25 –T– SEATING PLANE G 22X How to reach us: USA / EUROPE / Locations Not Listed: Motorola Literature Distribution; P.O. Box 5405, Denver, Colorado 80217. 303–675–2140 or 1–800–441–2447 Mfax : RMFAX0@email.sps.mot.com – ...