TDA7575B Datasheet, PDF (17/32 Pages) STMicroelectronics – 2 x 75W multifunction dual-bridge power amplifier with integrated digital diagnostics

TDA7575B
Figure 27. Timing diagram on the I²C bus
SCL
SDA
START
D99AU1032
Figure 28. Timing acknowledge clock pulse
SCL
1
2
3
7
SDA
START
MSB
D99AU1033
I2C bus interface
I²CBUS
STOP
8
9
ACKNOWLEDGMENT
FROM RECEIVER
5.5
1Ω capability setting
It is possible to drive 1Ω load paralleling the outputs into a single channel.
In order to implement this feature, outputs are to be connected on the board as follows:
OUT1+ (PIN35 and PIN36) shorted to OUT2+ (PIN19 and PIN20)
OUT1- (PIN28 and PIN29) shorted to OUT2- (PIN26 and PIN27).
It is recommended to minimize the impedance on the board between OUT2 and the load in
order to minimize THD distortion. It is also recommended to control the maximum mismatch
impedance between V_CC pins (PIN21/PIN22 respect to PIN33/PIN34) and between
PWGND pins (PIN24/PIN25 respect to PIN30/PIN31), mismatch that must not exceed a
value of 20 mΩ.
With 1Ω feature settled the active input is IN2 (PIN17 and PIN18), therefore IN1 pins should
be let floating.
It is possible to set the load capability acting on 1Ω pin as follows:
1Ω PIN (PIN15) < 1.5V: two channels mode (for a minimum load of 2Ω)
1Ω PIN (PIN15) > 2.5V: one channel mode (for 1Ω load).
IT IS TO REMEMBER THAT 1
OHM FUNCTION IS A HARDWARE SELECTION.
Therefore it is recommended to leave 1Ω PIN floating or shorted to GND to set the two
channels mode configuration, or to short 1Ω PIN to V_CC to set the one channel (1Ω)
configuration.
5.6
I²C abilitation setting
It is possible to disable the I²C interface by acting on I²C PIN (PIN16) and control the
TDA7575B by means of the usual ST-BY and MUTE pins. In order to activate or deactivate
this feature, I²C PIN must be set as follows:
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