TDA1545 / TDA1543 and Vref (pin 7)

[rfbrw]

You ask the question above and at the same time challenge the datasheet.

 

[abraxalito]

Also: Search DS for "Vref". Hits = 4x
Also, pg. 6:

None of those 'VREF' references refer to pin7.

Regardless ... is the 0.83V regulator for the TDA1545A VREF really an "ineffective design"? If so, why?

Its ineffective because treating that pin as VREF makes the output current unpredictable. The range of values for RREF is 7k4 thru 14k6 therefore 0.83V applied to those resistance values gives a range of IREF from 57uA to 112uA. Giving an output full-scale current range from 750uA to 1.48mA. So if you want a typical 2VRMS output, what value of I/V resistor to choose?