TFA9812_2 © NXP B.V. 2009. All rights reserved.
Preliminary data sheet Rev. 02 — 22 January 2009 11 of 66
NXP Semiconductors TFA9812
BTL stereo Class-D audio amplifier with I2S input
[1] Under these conditions the mode is enabled by the appropriate I2C setting.
In I2S slave mode selection between BCK and MCLK clock modes is automatic.
MCLK clock mode is given higher priority than BCK. If the MCLK clock is judged valid by
the protection circuit then MCLK clock mode is enabled. BCK clock mode is enabled when
the MCLK clock is invalid (e.g. not available) and the BCK clock is judged valid by the
protection circuit (see Section 8.7.11).
Table 7 shows the supported crystal frequencies in I2S master mode.
Table 8 shows the supported MCLK frequencies in MCLK mode (I2S slave mode).
Table 9 shows the supported BCK frequencies in BCK mode (I2S slave mode).
Table 6. I2S master/slave mode selection
Pin value Clock mode I2S mode
CSEL SDA/MS
0 0 legacy slave
0 1 legacy master
1- I
2C slave or master[1]
Table 7. Valid crystal frequencies in I2S master mode
Control mode fs (kHz) Crystal frequency (MHz)
I2C 8, 16, 32, 64, 128 8.192
11.025, 22.05, 44.1, 88.2,
176.4 11.2896
12, 24, 48, 96, 192 12.288
Legacy 32 8.192
44.1 11.2896
48 12.288
Table 8. Valid MCLK frequencies in I2S slave mode
Control mode fs (kHz) MLCK frequency (MHz)
I2C 8, 16, 32, 64, 128 8.192
12.288
32 18.432 (576 fs)
11.025, 22.05, 44.1, 88.2,
176.4 11.2896
16.9344
44.1 25.4016 (576 fs)
12, 24, 48, 96, 192 12.288
18.432
48 27.648 (576 fs)