Circuit description

AN2542

2/16

1

Circuit description

1.1

Block diagram

stream received by the RF antenna is sent to the BT-STA2416C2, a highly integrated

module able to communicate wirelessly with BTA2DP sources such as cellular phones,

BT Dongles and Notebook PCs.

Whilst streaming audio the receiver manages the BT data in the BT-STA2416C2 module,

transferring them to the STA529, an IC comprising a digital stereo class-D audio amplifier, a

DSP and a CMOS power output stage based on the FFX technology. The STA529 is

dedicated to the decoding and the generation of the PWM analog output.

A low-pass filter stage cuts the high frequencies of the PWM signal before amplification to a

standard line-out signal of 1 Vpp.

Figure 2.

Circuit block diagram

1.2

Schematic

Figure 3, Figure 4 and Figure 5 make up the overall schematic. You can zoom in to see the

http://www.st.com/stonline/products/applications/blocks/consumer/conb005.shtml.

BT-STA2416C2

Receiver module

STA529

Codec

Low-pass

filter

TS462

Dual op-amp

XTAL

13 MHz

Stream

connection

indicator

3.3 V

Stereo

line out

1 Vpp

BTA2DP