© 2009 Fairchild Semiconductor Corporation

www.fairchildsemi.com

FSA2000

• Rev. 1.0.0

3

Functional Diagram

Functional Mode

Power Down

Audio Power Down

Transient

Suppression

Audio Mode

USB Mode

V

BUS

LOW

LOW

LOW

LOW

HIGH

V

CC

LOW

HIGH

HIGH

HIGH

X

(1)

/SHDN

X

(1)

LOW

HIGH

HIGH

X

(1)

MUTE

X

(1)

X

(1)

HIGH

LOW

X

(1)

Charge Pump

OFF

OFF

ON

ON

OFF

R/L Amplifiers

OFF

OFF

OFF

ON

OFF

D+/R, D-/L

HI-Z

HI-Z

D+/R, D-/L=0V

R/L

D+/D-

Figure 3 Label

A

B

C

D

E

Notes:

1.

The (X) indicates “Don’t Care” state.

Figure 3. Functional Diagram



Audio Power Down

–An active-LOW shutdown pin (/SHDN) allows the amplifiers to be placed in low-power

(or shutdown) mode to conserve battery power. While the FSA2000 is in shutdown mode, USB data transfers are



Transient Suppression

– The FSA2000 audio amplifier has a soft turn-on feature that suppresses click and pop on

the audio path when the path is selected. In addition to the soft turn-on feature of the amplifier, the MUTE pin mutes

the audio path when asserted HIGH. The mute functionality also has an internal pull-down that disables mute if the

MUTE pin is floated. The MUTE pin allows control of the mute functionality by the application. Please refer to

application note AN-8031, describing the recommended timing and control of MUTE for optimal performance.

V

BUS

D+

D-

D+/R

D-/L

R

L

MUTE

/SDHN

V

CC

Audio

Control

USB

Control

A

B

C

D

E

Audio Mode

USB Mode

C

B