Datasheet CMX655A, CMX655D (CML Microcircuits) - 6

Ultra-Low Power Voice Codec CMX655D/CMX655A
History Version Changes Date
1 Document title changed to “CMX655D/CMX655A Ultra Low-Power Codec” 8th August 2018 Section 7.2 – Typical Performance Characteristics graphs added Section 5.6.7 – Automatic Level Control: description and associated register tables “greyed out” pending further revision 2 Revised performance figures 3rd September 2018 3 First public release 19th October 2018 This is Provisional Information; changes and additions may be made to this specification. Parameters marked TBD or left blank will be included in later issues. Items that are highlighted or greyed out should be ignored. These will be clarified in later issues of this document.  2018 CML Microsystems Plc 6 D/655/3 Document Outline Datasheet Front Page 1 Brief Description 2 Block Diagram 2.1 CMX655A 2.2 CMX655D 3 Pin List 3.1 CMX655A 3.2 CMX655D 4 External Components 4.1 CMX655A 4.1.1 Power Supply and Pin Decoupling 4.1.2 SPI 4.1.3 TWI 4.1.4 Speaker and Microphone 4.2 CMX655D 4.2.1 Power Supply and Pin Decoupling 4.2.2 SPI 4.2.3 TWI 4.2.4 Speaker and Microphone 5 General Description 5.1 Power Management 5.1.1 External Supplies 5.1.2 Regulated Supplies 5.2 Device Reset 5.2.1 Power-On-Reset 5.2.2 Reset Pin 5.3 Main Clock 5.3.1 Clock Frequency 5.3.2 Clock Generation 5.3.3 PLL 5.3.4 Low Power Oscillator 5.3.5 Clock Control Registers 5.3.5.1 CLKCTRL ($03) 5.3.5.2 RDIVHI ($04) 5.3.5.3 RDIVLO ($05) 5.3.5.4 NDIVHI ($06) 5.3.5.5 NDIVLO ($07) 5.3.5.6 PLLCTRL ($08) 5.4 Microphone Interface 5.4.1 Digital Microphone Interface 5.4.2 Analogue Microphone Interface 5.5 Class-D Amplifier 5.5.1 Audio Outputs 5.5.2 Overload Current Protection 5.5.3 Thermal Protection 5.5.4 Clipping Detection 5.6 Audio Signal Processing 5.6.1 Record Level Control 5.6.1.1 Record Level Control Register 5.6.2 Automatic Gain Control 5.6.2.1 AGC Registers 5.6.3 Noise Gate 5.6.3.1 Noise Gate Registers 5.6.4 Record Level Detection 5.6.4.1 Record Level Detection Registers 5.6.5 Playback Preamplifier Gain 5.6.5.1 Playback Preamplifier Gain Register 5.6.6 Playback Volume Control 5.6.6.1 Playback Volume Register 5.6.7 Automatic Level Control 5.6.7.1 ALC Registers 5.6.8 Digital Sidetone 5.6.8.1 Digital Sidetone Register 5.6.9 Voice Filters 5.6.9.1 Low Pass Filter 5.6.9.2 DC Blocking Filter 5.6.9.3 High Pass Filter 5.6.9.4 Voice Filters Registers 5.6.10 Channel Multiplexing 5.6.11 Click-and-Pop Reduction 5.6.11.1 Click-and-Pop Reduction Register 5.7 Control Interface 5.7.1 SPI Slave 5.7.2 TWI Slave 5.8 Serial Audio Interface 5.8.1 I2S Mode 5.8.2 Left-Justified Mode 5.8.3 PCM Mode 5.8.4 Audio Companding 5.8.5 Serial Audio Interface Registers 5.9 Interrupt Status and IRQN Pin 5.9.1 Interrupt Registers 5.10 System Control 5.10.1 System Control Registers 5.11 Register Address Map 6 Application Notes 6.1 Programming Examples 6.1.1 Start-up 6.1.2 DC-offset Calibration 6.1.3 Configuration 6.1.4 Enable Audio Channels 6.1.5 Shutdown 7 Performance Specification 7.1 Electrical Performance 7.1.1 Absolute Maximum Ratings 7.1.2 Operating Limits 7.1.3 Operating Characteristics 7.1.3.1 DC Parameters 7.1.3.2 AC Parameters 7.1.3.3 SPI 7.1.3.4 TWI 7.1.3.5 SAI 7.1.3.6 Digital Microphone Interface 7.2 Typical Performance Characteristics 7.2.1 THD+N vs. Level performance 7.2.2 THD+N vs. Frequency performance 7.2.3 Class D Amplifier Efficiency 7.2.4 Filter Performance Speaker Channel 7.2.5 Filter Performance Microphone Channel 7.3 Packaging 7.3.1 CMX655D/CMX655A End of Document