CS47L35 datasheet(29/300 Pages) CIRRUS

29 / 300 page

DS1085F3

CS47L35

4.2 Input Signal Path

The CS47L35 supports up to 16 GPIO pins, offering a range of input/output functions for interfacing, for detection of

external hardware, and for providing logic outputs to other devices. The GPIOs are multiplexed with other functions.

Comprehensive interrupt functionality is also provided for monitoring internal and external event conditions.

A signal generator for controlling haptics devices is included, compatible with both eccentric rotating mass (ERM) and

linear resonant actuator (LRA) haptics devices. The haptics signal generator is highly configurable and can execute

programmable drive event profiles, including reverse drive control. An external vibe actuator can be driven directly by the

Class D speaker output or

The CS47L35 incorporates four general-purpose timers, providing support for the sensor-hub connectivity. Sensor event

logging, and other real time application functions, allows many advanced functions to be implemented with a high degree

of autonomy from a host processor.

A smart accessory interface is included, supporting most standard 3.5-mm accessories. Jack detection, accessory

sensing, and impedance measurement is provided, for external accessory and push-button detection. Accessory detection

can be used as a wake-up trigger from low-power standby. Microphone activity detection with interrupt is also available.

System clocking can be derived from the MCLK1 or MCLK2 input pins. Alternatively, the SLIMbus interface, or the audio

interfaces (configured in Slave Mode), can be used to provide a clock reference. The integrated FLL circuit provides

support for a wide range of clocking configurations, including the use of a 32-kHz input clock reference.

The CS47L35 can be powered from 1.8- and 1.2-V external supplies. A separate supply (4.2 V) is typically required for the

Class D speaker driver. Integrated charge-pump and LDO-regulator circuits are used to generate supply rails for internal

functions and to support powering or biasing of external microphones.

4.2 Input Signal Path

The CS47L35 provides flexible input channels, supporting up to six analog inputs or up to four digital inputs. Selectable

combinations of analog (mic or line) and digital inputs are multiplexed into two stereo input signal paths.

The analog input paths support single-ended and differential modes, programmable gain control, and are digitized using

a high performance sigma-delta ADC.

The digital input paths interface directly with external digital microphones; a separate microphone interface clock is

provided for two separate stereo pairs of digital microphones. Digital delay can be applied to any of the digital input paths;

this can be used for phase adjustment of any digital input, including directional control of multiple microphones.

Two microphone bias (MICBIAS) generators provide a low-noise reference for biasing electret condenser microphones

(ECMs) or for use as a low-noise supply for MEMS microphones and digital microphones. Switchable outputs from the

MICBIAS generators allow four separate reference/supply outputs to be independently controlled.

Digital volume control is available on all inputs (analog and digital), with programmable ramp control for smooth, glitch-free

operation.

The IN1 and IN2 signal paths and control fields are shown in Fig. 4-2.

CS47L35 Datasheet(PDF) 29 Page - Cirrus Logic