TFA9879 NXP Semiconductors, TFA9879 Datasheet - Page 22

• Manufacturer Part Number: TFA9879
• Description: The TFA9879 contains a processor that supports a range of sound processing featuresincluding a 5-band parametric equalizer, separate bass and treble control, a dynamicrange compressor, soft clip control and volume control
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TFA9879
Product data sheet
9.3 Class-D amplification and clip control
9.4 Protection
The maximum peak output voltage for the first ten power limiter gain settings is given in
Table
Table 13.
All parameters are guaranteed for V
T
[1]
[2]
A fourth order sigma delta PWM converter converts the digital audio streams into 3-level
modulated PWM signals. The analog back end amplifies the two PWM signals in a BTL
configuration with complementary output stages.
One of two clip control configurations can be selected:
If smooth clipping is selected (CLIPCTRL = 0; see
have no artefacts. To obtain the maximum possible output power, the device can be set to
maximum power.
The PWM frequency is related to the I
Table 14.
The TFA9879 incorporates a wide range of protection circuits to facilitate optimal and safe
application.
The following protection circuits are included in the TFA9879:
Control value
00h
01h
02h
03h
04h
PWM frequency (kHz)
256
352.8
384
05h
06h
07h
08h
09h
amb
•
•
[2]
The control value is selected via bits P_LIM in the De-emphasis, soft/hard mute and power limiter control
register (see
Default value.
Smooth clipping, clip control on
Maximum power, clip control off
= 25
13.
°
C unless otherwise specified.
Power limiter control settings
Power limiter control settings
[1]
Table
All information provided in this document is subject to legal disclaimers.
32).
Rev. 02 — 15 October 2010
Power limiter gain (dB)
0.0
−0.5
−1.0
−1.5
−2.0
−2.5
−3.0
−3.5
−4.0
−4.5
Sample rate (kHz)
8, 16, 32, 64
11.025, 22.05, 44.1, 88.2
12, 24, 48, 96
DDP
Mono BTL class-D audio amplifier with digital input
= 5 V; no load; f
2
S input sample rate as detailed in Table 4.
i
Table
= 1 kHz; f
Maximum peak output voltage (V)
V
V
V
V
4.7
4.4
4.2
4.0
3.7
3.5
SCK relative to sample rate
32 ×, 64 ×
32 ×, 64 ×
32 ×, 64 ×
DDP
DDP
DDP
DDP
27), the clipping behavior will
s
= 48 kHz; clip control off;
TFA9879
© NXP B.V. 2010. All rights reserved.
22 of 60