CS4299 datasheet(45/52 Pages) CIRRUS

45 / 52 page

CS4299

Analog Reference, Filters, and Configuration

REFFLT - Internal Reference Voltage, Input, Pin 27

This signal is the voltage reference used internal to the CS4299. A 0.1

µF and a 1.0 µF (must not be

larger than 1

µF) capacitor with short, wide traces must be connected to this pin. No other connections

should be made to this pin.

Vrefout - Voltage Reference, Output, Pin 28

All analog inputs and outputs are centered around Vrefout, nominally 2.3 Volts. This pin may be used to

level shift external circuitry. This pin cannot drive any DC loads, thus any external loading must be

buffered.

AFLT1 - Left ADC Channel Antialiasing Filter, Input, Pin 29

This pin needs a 1000 pF NPO capacitor connected to analog ground.

AFLT2 - Right ADC Channel Antialiasing Filter, Input, Pin 30

This pin needs a 1000 pF NPO capacitor connected to analog ground.

FLTI, FLTO - 3D Filter, Input, Pin 33 and 34

A 1000 pF capacitor must be connected between FLTI and FLTO if the 3D function is used.

FLT3D - 3D Filter, Input, Pin 32

A 0.01

µF capacitor must be connected from this pin to AGND if the 3D function is used.

BCFG - Beep Configuration, Input, Pin 31

This pin is the configuration control for the PC_BEEP bypass path. If this pin is grounded, the bypass

path is disabled. If this pin is left floating, the PC_BEEP bypass path is enabled.

Misc. Digital Interfaces

S/PDIF_OUT - Sony/Philips Digital Interface, Output, Pin 48

This pin generates the S/PDIF digital output from the CS4299 when the SPEN bit in the S/PDIF Control

transformer to an RCA-type connector for use with consumer audio equipment.

EAPD - External Amplifier Powerdown, Output, Pin 47

This pin is used to control the powerdown state of an audio amplifier external to the CS4299. The

output is controlled by the EAPD bit in the Powerdown Ctrl/Stat Register (Index 26h). It is driven as a

normal CMOS output and defaults low (‘0’) upon power-up.

CS4299 Datasheet(PDF) 45 Page - Cirrus Logic