Datasheet CMX655A, CMX655D (CML Microcircuits) - 9

Ultra-Low Power Voice Codec CMX655D/CMX655A
Table 2 CMX655A Pin List by Group Number Name Type Function Power
2 VDD_PA VDD Class-D Supply: 2.7-3.6V (high current) 4 VDD_A VDD 1.2V Analogue Regulator Decouple 10 VDD_AD VDD Analogue/Digital Supply 2.7-3.6V (1.75-3.6V if VDD_PA unused) 24 VSS_PA GND Class-D Ground PADDLE DGND GND Digital and Analogue Ground
Reference and Bias
5 BIAS AI Bias Current Resistor 6 VCM AO Common Mode Voltage Decouple 7 VREF AO ADC Reference Voltage Decouple
Class-D Amplifier Outputs
1 AOUTN AO Class-D Amplifier Output Negative 3 LOUT AO Lineout 23 AOUTP AO Class-D Amplifier Output Positive
Microphone Interface
8 LIN AI Analogue Microphone Left Input 9 RIN AI Analogue Microphone Right Input
General System & Control
11 RSTN DI Active Low Reset 12 RCLK DI PLL Reference/Main clock 18 IRQN DO Active Low Interrupt. Open-drain - connect to VDD_AD via pull-up
Control Interface
17 SPIS DI SPI Select: 0=TWI, 1=SPI 19 SCLK/SCL DI SPI SCLK/TWI SCL 20 MISO/SDA DIO SPI MISO/TWI SDA 21 MOSI/A1 DI SPI MOSI/TWI A1 22 CSN/A0 DI SPI CSN/TWI A0
Serial Audio Interface
13 LRCLK/FS DIO Left-Right Clock/PCM Frame Sync/PLL Reference 14 SDI DI Serial Audio Data Input 15 SDO DO Serial Audio Data Output 16 BCLK DIO Serial Audio Data Clock AIO Analogue Input / Output DIO Digital Input / Output AI Analogue Input DI Digital Input AO Analogue Output DO Digital Output VDD Supply GND Ground  2018 CML Microsystems Plc 9 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