TFA9879 NXP Semiconductors, TFA9879 Datasheet - Page 24

• 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
Table 15.
10. I
TFA9879
Product data sheet
Protection circuits
Symbol Conditions
OTP
OCP
UFP
OFP
IBP
2
C-bus interface and register settings
I
PWM frequency <
96 kHz
PWM frequency >
1031 kHz
SCK/WS is not 16 ± 1, 32 ± 1,
48 ± 1, 64 ± 1 or 128 ± 1
T
O
j
Overview of protection circuits
> 130 °C
> I
O(ocp)
9.4.4 OverFrequency Protection (OFP)
9.4.5 Invalid Bit-clock Protection (IBP)
9.4.6 Overview of protection circuits
10.1 I
OFP sets the output stages floating when the clock input source is too high (>f
can happen if, for example, the selected sample frequency (bits I2S_FS in
in line with the applied sample rate. The PWM controller can become unstable when the
frequency of the input clock is higher than the selected sample frequency. Without OFP,
peripheral devices in an application might be damaged.
The OFP status can be monitored by polling the I
will be raised when the input sample rate is too high.
If the SCK-to-LRCK ratio is not supported, the audio signal will be distorted. This occurs
because the sound processing blocks will be operating at frequencies out of
synchronization with the sample rate.
IBP prevents this happening by shutting down the TFA9879 if the IBP alarm is raised for
the selected channel. This will disconnect the digital audio path.
Valid SCK-to-LRCK ratios for PCM interface formats are 16, 32, 48, 64, 96, 128 and 192.
For I
Table 15
The TFA9879 supports the 400 kHz I
I
The TFA9879 can operate only in I
transmitter.
2
2
C-bus is used to control the TFA9879 and to transmit and receive data.
C-bus interface
2
S interface formats, valid SCK-to-LRCK ratios are 32 and 64.
provides an overview of the protection circuits implemented.
I
OTP
OCP
UFP
OFP
IBP
All information provided in this document is subject to legal disclaimers.
2
C flag
Rev. 02 — 15 October 2010
Output
floating
floating
floating
floating
floating
Mono BTL class-D audio amplifier with digital input
2
C slave mode, as a slave receiver or as a slave
restart (fault to operating when SCK/WS is 16 ± 1, 32 ± 1,
2
Recovery
automatic when timer set to 4.5 μs, 100 ms or 1 s (via bits
L_OTP in
via I
automatic when timer set to 4.5 μs, 27.5 μs or 10 μs (via
bits L_OCP in
via I
restart (fault to operating when PWM frequency > 96 kHz)
restart (fault to operating when PWM frequency <
1031 kHz)
48 ± 1, 64 ± 1 or 128 ± 1)
C-bus microcontroller interface mode standard. The
2
2
C-bus when no recovery is selected
C-bus when no recovery is selected
Table
2
Table
C status register
27) and T
27) and I
j
< 130 °C;
O
< I
(Table
O(ocp)
TFA9879
© NXP B.V. 2010. All rights reserved.
;
Table
33). The alarm
OFP
22) is not
). This
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