TDA7786 datasheet(15/54 Pages) STMICROELECTRONICS

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TDA7786, TDA7786M

Function description

2.12

Digital high speed IO interface pins

The IC has several IOs tasked for connectivity to an external HD Radio™ decoder and/or to

I2S audio sources and destinations (pins 37 to 44).

These pins are driven by a special buffer that has been developed to reduce disturbance

originating from activity on the digital lines. This bidirectional buffer is based on a TTL

Schmitt trigger receiver and a slew-rate controlled driver with programmable cut-off

frequency and current capability.

Typical configurations of these IOs for both analog and digital-HD reception are indicated in

Table 3; for the suggested configuration all the slew-rate controlled pads are programmed

with a 10 MHz cut-off frequency:

In case a different GPIO configuration is used, it is recommended to connect the TDA7786x

to an externally regulated 3.3 V source.

2.13

Multipath reduction

The TDA7786 is equipped with a basic FM multipath noise reduction system in addition to

the traditional weak signal processing. The algorithm, called DANCE, assures an improved

performance in presence of in-band interference (such as in case of multipath).

The premium version of the ELITE family, the TDA7786M is equipped with a superior

algorithm, called MuSICA, to further enhance the reception quality even in presence of

strong multipath.

Table 3. Suggested GPIO direction and driving capability

Use case:

HD reception

Use case:

digital audio out

Driving capability

10 pF

5 pF

OUT

TDA7786 数据表(PDF) 15 Page - STMicroelectronics