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AN1656 APPLICATION NOTE

Additional Features:

Acting on the

button

is shown the registers' table, where is shown the current value of all the de-

vice's registers. It is real time updated as the user modifies any parameter. It is possible to entry directly

a value in binary, hexadecimal or decimal notation by clicking on the correspondent cell and inserting a

new value.

The send command

refresh all registers of the device with current settings.

It may use the incremental mode it is enabled.

PCB and Components Layout

In fig.2 is shown how to connect the two boards TDA7448 and SAM351 in order to have a complete am-

To complete the application it is necessary to provide the correct Power Supply for the two boards as fol-

lows:

TDA7448: (connector J6)

The supply voltage to be used can range from +5 up to +10V

SAM351: (connector J9)

SAM351 module utilize two supply voltages:

– Signal Supply Voltage +/-Vs: +/- 24Vdc / 100mA

– Power Section Voltage +/-DC: +50V /4.0A

In the dimensioning of the power section is important to know that the module is able to provide the max-

imum power (@THD=10%) on two channels and instantaneously 1/3 Max Pout on the remaining outputs

or continuously 1/8 of Max. Pout.

The two supply voltages are completely separated between them: the signal VS is splitted (+/-24V) and

its central point (A-gnd) is the reference ground for the STA575 circuits (inputs, stand-by, etc.), while the

Power DC is a single supply and its reference must be completely isolated from A-gnd.

In order to implement the Mute function for the SAM351 module it is necessary to connect a wire to the

pin.9 of the connector J8:

– when pin.9 open: SAM351 module is Muted

– when pin.9 is at 15V: SAM351 module is in Play.

All the 6 channels are configurated in BTL and completely separated among them and isolated from the

rest of the system.