CRD44800 Cirrus Logic Inc, CRD44800 Datasheet
CRD44800
Specifications of CRD44800
Related parts for CRD44800
CRD44800 Summary of contents
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... V supply (at 10% THD+N). A 155 W Switched Mode Power Supply (SMPS) is used to power the CRD44800. As shown below, the CS44800 IC takes four stereo dig- ital audio inputs in I²S format and converts them to PWM outputs. This 64-pin LQFP IC provides an integrated ...
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... TABLE OF CONTENTS 1. SCHEMATIC DESCRIPTIONS ................................................................................................. 3 1.1 CRD44800 PWM Amplifier ................................................................................................ 3 1.2 CRD44800 Driver Board .................................................................................................... 3 1.3 Switched Mode Power Supply ........................................................................................... 4 2. OPERATION INFORMATION ................................................................................................... 5 2.1 Power Supply Ratings ...................................................................................................... 10 2.2 Power Supply Decoupling ................................................................................................ 10 2.3 Electromagnetic Interference (EMI) ................................................................................. 11 2.3.1 Suppression of EMI at the Source ...................................................................... 11 3. SCHEMATICS ......................................................................................................................... 13 4. LAYOUT .................................................................................................................................. 20 5 ...
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... Table 1. RMS Output Voltage for Given Load Impedance 1.2 CRD44800 Driver Board The CRD44800 Driver board provides a convenient source of PCM I²S signals to drive the CRD44800 PWM Amplifier board. Eight analog inputs allow multi-channel analog audio sig- nals to be used for evaluation of the amplifier. In addition, either optical or coaxial stereo S/PDIF signals can be used to evaluate the amplifier ...
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... All aspects of the CS44800 may then be evaluated using the supplied software. 1.3 Switched Mode Power Supply The SMPS used for the CRD44800 is a 155W OEM supply. The supply provides +45V for the TDA8939 PWM back ends, and +5V to power all the signal level circuitry. The SMPS is fully over-current and over-temperature protected. ...
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... Switches and Indicators (Located on the Driver Board): RESET Pushbutton (S1) - forces a complete system reset. MUTE Pushbutton (S2) - mutes the audio output of the CRD44800, but the PWM output stage will continue switching. RAMP UP/DN Pushbutton (S3) - forces a ramp down or a ramp up of the PWM switching output. ...
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... The Fault and Mute LEDs will both light briefly as the system is initialized. Note that if either the Coax or the Optical input is selected, a valid digital signal must be provided to the selected input so that the CRD44800 can complete initialization valid signal is not present at the selected input, both the Fault and Mute LEDs will remain lit. ...
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... Optical S/PDIF Coaxial S/PDIF 4) Connect the DB-9 RS-232 port (J14) on the CRD44800 Driver board serial port. 5) Copy the CRD44800 directory from the included CD-ROM to the users local hard drive. Note that FlexGUI is only compatible with systems running Windows 98 or better (i.e. Windows 98, ME, 2000, XP, etc.). 6) Modify the following line in the file “ ...
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... Each device is displayed on a separate tab. Register values can be modified bitwise or bytewise. For bitwise, click the appropriate pushbutton for the desired bit. For bytewise, the desired hex value can be typed directly in the register address box in the register map. 8 Figure 2. CS44800 Dialog Tab CRD44800 ...
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... Figure 3. Advanced Register Debug Tab - CS44800 CRD44800 9 ...
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... While the PSR functionality of the CS44800 helps reduce power supply noise feedthrough to the output, careful decoupling of the power stage supply rails is essential. Referring to Figure 11, the top side of the CRD44800 PWM amplifier board, good decoupling practice is shown. Notice that the 0.1 physically possible to the power pins of the TDA8939 ...
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... This allows the speaker outputs decoupled to the chassis just before they exit the chassis from the speaker connector. Again, refer to Figure 11 for the preferred component lay- out. • Make use of source termination resistors on all digital signals whose traces are longer CRD44800 11 ...
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... It is extremely critical that the layout of the power amplifier section of the Cirrus Logic CS44800 Reference Design be copied as exactly as possible to assure best RF/EMI per- formance. 12 CRD44800 ...
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... SCHEMATICS CRD44800 13 ...
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... LAYOUT 20 CRD44800 ...
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... BILL OF MATERIALS CRD44800 23 ...
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... TYPICAL PERFORMANCE PLOTS CRD44800 25 ...
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... Cirrus Logic, Cirrus, the Cirrus Logic logo designs, and Popguard are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be trademarks or service marks of their respective owners. Changes 1st Release 2nd Release -Updated schematics and layout to reflect rev B. Table 2. Revision History CRD44800 29 ...