Datasheet

InvertingInput
–In
TAS5717
R1
R2
+
–
C3
R3
C1
C2
S0447-01
SupplyRamp
Supply
HP_SD
Timefor AC-Coupling
CapacitorstoCharge
T0463-01
TAS5717
TAS5719
www.ti.com SLOS655A –NOVEMBER 2010–REVISED FEBRUARY 2011
The component values can be calculated with the help of the TI FilterPro™ program available on the TI website
at:
http://focus.ti.com/docs/toolsw/folders/print/filterpro.html
Figure 49. Second-Order Active Low-Pass Filter
The resistor values should have a low value for obtaining low noise, but should also have a high enough value to
get a small size ac-coupling cap. C2 can be split in two with the midpoint connected to GND, this can increase
the common-mode attenuation.
Pop-Free Power Up
Pop-free power up is ensured by keeping the HP_SD low during power supply ramp up and down. The pin
should be kept low until the input AC-coupling capacitors are fully charged before asserting the HP_SD pin high,
this way proper pre-charge of the ac-coupling is performed and pop-less power-up is achieved. Figure 50
illustrates the preferred sequence.
Figure 50. Power-Up/Down Sequence
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Product Folder Link(s): TAS5717 TAS5719