Cirrus Logic, Inc. Ultra Low Power, Stereo Codec with Class H Headphone Amplifier CS42L56

The CS42L56 is a highly integrated, 24-bit, ultra low power stereo codec based on multi-bit Delta Sigma modulation. Both the ADC and DAC offer many features suitable for low power portable system applications. The CS42L56 includes a stereo ADC, stereo DAC, and stereo headphone driver. The analog input path includes independent channel control of a variety of features including a Programmable Gain Amplifier, digital volume control with soft ramp transitions, and an analog pass-through mode for low power operation. It also includes an analog input mux and mic bias generation for supporting a variety of analog audio inputs. The DAC output includes a DSP engine with parametric EQ, volume control, limiting functions, and a beep generator. The Class H stereo headphone amplifier combines the efficiency of an integrated step-down and inverting charge pump with the linearity and low EMI of a Class AB amplifier. The output is ground centered, eliminating the need for large DC blocking capacitors. The CS42L56 is available in a 40-pin QFN package for the Commercial (-40 to +85° C) grade. The CDB42L56 Customer Demonstration board is also available for device evaluation and implementation suggestions. Features Digital to Analog Features 5 mW Stereo playback power consumption 99 dB dynamic range (A-wtd) -86 dB THD+N Digital signal processing engine Bass & treble tone control, de-emphasis Master volume control (+12 to -102 dB in 0.5 dB steps) Soft-ramp & zero-cross transitions Programmable peak-detect and limiter Beep generator w/ full tone control Stereo Headphone and Line Amplifiers Step-down/inverting charge pump Class H amplifier - automatic supply adj. High efficiency Low EMI Pseudo-differential ground-centered outputs High HP power output at -75 dB THD+N 2 x 20 mW into 16 ω @ 1.8 V 1 VRMS line output @ 1.8 V Analog vol. ctl. (+12 to -60 dB in 1 dB steps) Analog in to analog out passthrough Pop and click suppression Analog to Digital Features 3.5 mW Stereo record power consumption 95 dB dynamic range (A-wtd) -87 dB THD+N Configurable analog inputs Two pseudo-differential Stereo inputs or One pseudo-differential Stereo inputs + one standard Stereo input + one standard mono input or Three standard Stereo inputs Pseudo-differential inputs reduce common mode signal noise 3:1 Stereo input MUX for ADC or passthrough Analog Programmable Gain Amplifier (PGA) +12 to -6 dB in 0.5 dB steps +10 dB or +20 dB additional gain for microphone inputs Programmable, low-noise MIC bias output Programmable Automatic Level Control (ALC) Noise gate for noise suppression Programmable threshold & attack/release rates Independent ADC channel control High-pass filter disable for DC measurements System Features Audio (11.2896 MHz or 12.288 MHz) or USB (12 MHz) master clock input Low-power operation Stereo analog passthrough: 3.3 mW @1.8 V Stereo record and playback: 8.3 mW @1.8 V Headphone detect input High performance 24-bit converters Multi-bit Delta Sigma architecture Integrated high efficient power management reduces power consumption Step-down charge pump improves efficiency Inverting charge pump accommodates low system voltage by providing negative rail for HP/line amp LDO Reg. provides low digital supply voltage Digital power reduction Very low ADC/DAC oversampling rate Bursted serial clock providing up to 24 bits per sample Power down management ADC, DAC, CODEC, PGA, DSP Analog & digital routing/mixes Line/headphone out = analog in (ADC Bypassed) Line/headphone out = ADC out Internal digital loopback Mono mixes I²C® or SPI™ control port I²S or left-justified digital interface format Flexible clocking options Master or slave operation Wide range of sample rates supported