CS4461-CZZ Cirrus Logic

CS4461 Multi-Bit A/D for Class-D Real-Time PSR Feedback Features General Description z Advanced Multi-bit Delta-Sigma Architecture The CS4461 is a complete analog-to-digital converter for class-D real-time power supply rejection (PSR) feed- z Real-time Feedback of Power Supply back. It performs sampling and analog-to-digital Conditions (AC and DC) conversion, generating digital data for input to a z Filterless Digital Output Resulting in Very Low class-D modulator with real-time PSR feedback Signal Delay capabilities. z 135 mW Power Consumption The CS4461 uses a 5th-order, multi-bit delta-sigma modulator followed by output data formatting. The ADC z Supports Logic Levels Between 3.3 V and uses a differential architecture which provides excellent 5.0 V noise rejection. z Differential Analog Architecture The CS4461 feeds back the AC and DC voltage compo- z Modulator Overflow Detection nents and is ideal for class-D audio systems requiring high power supply rejection. z Interfaces Directly to the CS44800/CS44600 Class-D PWM Modulator The CS4461 is available in a 24-pin TSSOP package in both Commercial (-10 to +70 C) and Automotive z Multi-bit Conversion at up to 7.5 MHz grade (-40 to +85 C). The CDB44800 Customer Dem- z Delivers Modulated Data Over 2-Wire Interface onstration board is also available for device evaluation and implementation suggestions. Please see Ordering Information on page 11 for complete details. VQ REFGND PSR RESET PSR EN FILT+ Voltage Reference OVERFLOW PSR MCLK AIN+ + Output Data LP Filter PSR SYNC Formatting AIN- PSR DATA - S/H DAC 5.0 V GND 3.3 V to 5.0 V (VA) (VDP) Copyright Cirrus Logic, Inc. 2005 SEPTEMBER 05 (All Rights Reserved) CS4461 TABLE OF CONTENTS 1. CHARACTERISTICS AND SPECIFICATIONS ..................................................................................... 3 2. PIN DESCRIPTIONS ............................................................................................................................. 6 3. TYPICAL CONNECTION DIAGRAM .................................................................................................... 7 4. APPLICATIONS .................................................................................................................................... 8 4.1 Digital Connections ......................................................................................................................... 8 4.2 Analog Connections ....................................................................................................................... 8 4.3 Power-Up Sequence ...................................................................................................................... 9 4.4 Overflow Detection ......................................................................................................................... 9 4.5 Grounding and Power Supply Decoupling ......................................................................................9 5. PACKAGE DIMENSIONS ................................................................................................................. 10 6. ORDERING INFORMATION ............................................................................................................... 11 7. REVISION HISTORY ........................................................................................................................... 11 LIST OF FIGURES Figure 1. Typical Connection Diagram......................................................................................................... 7 Figure 2. CS4461 Recommended Analog Input Buffer................................................................................8 2 DS650F1