SAA8200HL Datasheet, PDF (41/71 Pages) NXP Semiconductors – Ensation Base integrated wireless audio baseband

Philips Semiconductors
SAA8200HL
Ensation Base integrated wireless audio baseband
• Simple switched resistors architecture
• Data-weighted averaging technique reducing distortion
• Large supply voltage range (0.8 V to 3.6 V)
• Low noise (N > 100 dBA).
SAA8200HL
V_DD V_SS
V_{DDA(3V3_DAC)} V_{DAC_REFN}
V_{DAC_REFP}
DIN_L ^[23:0]
DIN_VALID
DIN_R ^[23:0]
SOUND CONTROL
INTERPOLATION FILTER
AND
NOISESHAPER
DAC
DAC
14 DAC_OUTL
16 HP_OUTL
18 HP_OUTC
HP
20 HP_OUTR
15 DAC_OUTR
Fig 10. Block diagram of the SDAC
001aab465
7.20.1.2 Functional description
The SDAC comprises the following functions:
• Sound feature processor
• Digital upsampling filter
• Noise shaper
• DAC.
Digital de-emphasis can be set by a 3-bit control bus (bits CTRL_INTI[18:16]) for the
range of sample frequencies available (32 kHz, 44.1 kHz, 48 kHz and 96 kHz). The
de-emphasis filters are only in the signal path for normal speed mode (data input at 1f_s).
In the interpolation filter a three stage linear digital volume control is provided with a range
from 0 dB to −89 dB and −∞ dB. Down to the attenuation of −50 dB the step size equals
0.25 dB, from −50 dB to −83 dB it equals 3 dB and the last step to −89 dB is one of 6 dB.
The attenuation for the left channel is controlled by bits CTRL_INTI[15:8]; the attenuation
for the right channel is controlled by bits CTRL_INTI[7:0].
When the left and right channels of the interpolator are muted (bit CTRL_INTI[19] = 1), the
gain in the interpolator is decreased to −∞ dB conforming to a raised cosine function to
avoid harsh audible plops (soft mute). This mute function is completed after a period of
128 samples in normal mode i.e. 2.9 ms at f_s = 44.1 kHz. When a complete mute is
achieved for both left and right channels, the bit CTRL_INTO[0] is made a logic 1. The
interpolator mute function is illustrated in Figure 11.
SAA8200HL_2
Preliminary data sheet
Rev. 02 — 17 October 2005
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
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