zxcd1000 Zetex Semiconductors plc., zxcd1000 Datasheet
zxcd1000
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zxcd1000 Summary of contents
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... From an acoustic point of view, even more important than the figures above, is that the residual distortion is almost totally free of any crossover artifacts. This allows the ZXCD1000 to be used in true hi-fi applications. This lack of crossover distortion, sets the ZXCD1000 solutions quite apart from most other presently available low cost solutions, which in general suffer from severe crossover distortion problems ...
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... ZXCD1000 ABSOLUTE MAXIMUM RATINGS Terminal Voltage with respect Power Dissipation Package Thermal Resistance ( ja ) Operating Temperature Range Maximum Junction Temperature Storage Temperature Range Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied ...
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... Audio Input for Channel A Triangle Input for Channel A Triangle Output No connection External timing capacitor node (to set the switching frequency) Triangle Output (for slave ZXCD1000 in stereo application) Triangle Input for Channel B Audio Input for Channel B Small Signal GND Channel B PWM Output to drive external Bridge MOSFETs Power GND (for Output Drivers) Internal Supply Rail (Decouple with 1µ ...
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... ZXCD1000 ZXCD1000 Class D controller IC A functional block diagram of the ZXCD1000 is shown in Figure 2. The on chip series regulators drop the external V CC supply (12V-18V) to the approximate 9V (9VA/9VB) and 5.5V (5V5) supplies required by the internal circuitry. A triangular waveform is generated on chip and is brought out at the OscA and OscB outputs. The frequency of this is set (to ~200kHz external capacitor (C osc ) and on chip resistor ...
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... OutA and OutB outputs. These in turn drive the speaker load (with the audio information contained in the PWM signal) via the off chip output bridge and single stage L-C filter network. ISSUE 2 - APRIL 2002 ZXCD1000 Triangle A/B Audio A/B O/P Comparator O/P (Duty Cycle = 50%) Figure 3b ...
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... NE5532 dual op-amp. One of these op-amps is configured as a voltage follower and the other inverting amplifier. This produces in phase and inverted signals for application to the ZXCD1000. The op-amp outputs are AC coupled into the ZXCD1000 Audio A and Audio B inputs via simple R-C low pass filters (R16/C3 and R15/C7) ...
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... A very important feature of the Zetex solution is that the residual distortion is almost totally free of any crossover artifacts. This lack of crossover distortion sets the ZXCD1000 solutions quite apart from most other presently available low cost solutions, which in general suffer from severe crossover distortion problems ...
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... This is undesirable. A stereo solution which avoids this problem can be achieved by synchronising the operating frequencies of both ZXCD1000’s class D controller IC’s, by slaving one device from the other. This is illustrated in Figure 8. MASTER Figure 8 Frequency synchronisation for stereo applications ...
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... ZXCD1000 ISSUE 2 - APRIL 2002 10 ...
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... MOSFET’s. The latter must be sufficiently enhanced by the OutA and OutB outputs to ensure the filter and load network is driven properly. If the gate drive of the ZXCD1000 is too low for the chosen MOSFET then the OUTA and OUTB signal must be buffered using an appropriate MOSFET driver circuit. Additionally, suitable magnetics are essential to achieve good THD performance ...
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... ZXCD1000 ISSUE 2 - APRIL 2002 12 ...
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... ZXCD1000 Solution performance figures Typical performance graphs for the Zetex 25W open loop solution are shown here for both 4 and 8Ω loads. These graphs further demonstrate the true high fidelity performance achieved by the Zetex solutions Output Power THD v Power into 8 at 1kHz ...
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... ZXCD1000 10W 1W 5W Output Power THD v Power into 4 at 1kHz f(Hz) Frequency response (4 load) Note roll off. This can be corrected by using an alternative values for output filter components. 20W f(Hz) FFT of distortion and noise floor load) f(Hz) FFT of distortion and noise floor at 20W (4 load) ...
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... SEATING PLANE SIDE VIEW ORDERING INFORMATION Device Description ZXCD1000EQ16 Class D modulator Information on Zetex reference designs, MOSFETs and demonstration boards can be obtain by contacting Zetex applications or by visiting www.zetex.com/audio © Zetex plc 2001 Zetex plc Zetex GmbH Fields New Road Streitfeldstraße 19 Chadderton D-81673 Mü ...