CS47L85 datasheet(68/370 Pages) CIRRUS

68 / 370 page

CS47L85

Rev 4.3

blocks.

The digital core provides parametric equalisation (EQ) functions, dynamic range control (DRC), low-pass / high-pass filters

(LHPF), and programmable DSP capability. The DSP can support functions such as wind noise, side-tone or other

programmable filters, also dynamic range control and compression, or virtual surround sound and other audio enhancements.

The CS47L85 supports multiple signal paths through the digital core. Stereo full-duplex sample rate conversion is provided

to allow digital audio to be routed between input (ADC) paths, output (DAC) paths, Digital Audio Interfaces (AIF1, AIF2, AIF3

and AIF4) and SLIMbus paths operating at different sample rates and/or referenced to asynchronous clock domains.

The DSP functions are highly programmable, using application-specific control sequences. It should be noted that the DSP

configuration data is lost whenever the DCVDD power domain is removed; the DSP configuration data must be downloaded

to the CS47L85 each time the device is powered up.

The procedure for configuring the CS47L85

DSP functions is tailored to each customer’s application; please contact your

local Cirrus Logic representative for more details.

The digital core incorporates a S/PDIF transmitter, which can provide a stereo S/PDIF output on a GPIO pin. Standard

S/PDIF sample rates of 32kHz up to 192kHz can be supported.

The CS47L85

incorporates two 1kHz tone generators which can be used for ‘beep’ functions through any of the audio signal

paths. A white noise generator is incorporated, to provide ‘comfort noise’ in cases where silence (digital mute) is not desirable.

A haptic signal generator is provided, for use with external haptic devices (e.g., mechanical vibration actuators). Two Pulse

Width Modulation (PWM) signal generators are also provided; the PWM waveforms can be modulated by an audio source

within the digital core, and can be output on a GPIO pin.

The CS47L85 also incorporates the Cirrus Logic Ambient Noise Cancellation (ANC) functionality; note that this is described

in a separate section, see “Ambient Noise Cancellation”.

An overview of the digital core mixing and signal processing functions is provided in Figure 22.

The control registers associated with the digital core signal paths are shown in Figure 23 through to Figure 39. The full list

of digital mixer control registers (Register R1600 through to R3192) is provided in a separate document -

see “Register Map”

for further information. Generic register definitions are provided in Table 8.

CS47L85 Datasheet(PDF) 68 Page - Cirrus Logic