tfa9879hn NXP Semiconductors, tfa9879hn Datasheet - Page 22

• 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
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. 01 — 8 April 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.
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