tfa9879hn NXP Semiconductors, tfa9879hn Datasheet - Page 13

• Manufacturer Part Number: tfa9879hn
• Description: Mono Btl Class-d Audio Amplifier For Portable Applications With Digital Input
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TFA9879_1
Preliminary data sheet
The transfer function of this all-pass filter is given in
A(z) is the second order filter structure. The transfer function of A(z) is given in
Equation
Z
K
Equation 5
Equation 6
The ranges of the parametric equalizer settings for each band are:
Filter coefficients need to be entered for each filter stage via the I
configure the filters (see
Figure
The relationships are symmetrical for the suppression and amplification functions. A
skewing effect can be observed at higher frequencies.
H z  
A z  
K
K
Fig 6.
1
0
•
•
•
2
2
, K
equals one f
=
=
The gain, G, is from 30 dB to +12 dB.
The center frequency, f
The quality factor, Q, is from 0.001 to 8.
1
=
=


and K
2Q G
2Q
7,
------------------------------------------------------------------------------ -
1
1 2 
K
Figure 8
Regalia-Mitra filter flow diagram
4:
K
+

–
X(z)
1
1
can be used to calculate band suppression (G < 1) functions.
can be used to calculate band amplification (G  1) functions.
K
K
+
2
sin

K
2
=
0

–
and the filter parameters G,  and Q is shown in
K
1
1

K

=
–
s
All information provided in this document is subject to legal disclaimers.

sin
2
s
+
=
1
0
cos


delay period. The relationship between the programmable parameters
G
A z  


+
and
=

–

1

K
cos
2Q

+
G

1


Figure 9
 Z
K

2Q G
+
Rev. 01 — 8 April 2010
+

1
A(z)
Section
 Z
K
sin
1 –


c
0
, is from 0.0004 ´ f

2 
+
1 –

+
K

+
illustrate some possible equalizer band transfer functions.
G 1
+
1
sin

10.4.3).
1 A z  

Z

Mono BTL class-D audio amplifier with digital input
2 –
Z
–

2 –
−

G 1
+


+
s
½
to 0.49 ´ f
K
Equation
0
/2
s
.
3:
Equation 5
2
C-bus interface to
TFA9879
© NXP B.V. 2010. All rights reserved.
010aaa406
and
Y(z)
Equation
13 of 60
(3)
(4)
(5)
(6)
6.