CRD4525-Q1 Cirrus Logic Inc, CRD4525-Q1 Datasheet - Page 31

• Manufacturer Part Number: CRD4525-Q1
• Description: REFERENCE BOARD FOR CS4525 PWM
• Manufacturer: Cirrus Logic Inc
• Series: Popguard®r

Specifications of CRD4525-Q1

• Amplifier Type: Class D
• Output Type: 2-Channel (Stereo)
• Max Output Power X Channels @ Load: 15W x 2 @ 8 Ohm
• Voltage - Supply: 12 V ~ 18 V
• Operating Temperature: 0°C ~ 70°C
• Board Type: Fully Populated
• Utilized Ic / Part: CS4525
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 598-1586

DS726PP3
6.1.4.4
The CS4525 includes an on-chip digital de-emphasis filter optimized for a sample rate of 44.1 kHz to ac-
commodate audio recordings that utilize 50/15 µs pre-emphasis equalization as a means of noise reduc-
tion. The filter response is shown in
DeEmph bit in the Tone Config register.
6.1.4.5
The CS4525 implements configurable bass and treble shelving filters to easily accommodate system tone
control requirements. Each shelving filter has 4 selectable corner frequencies, and provides a cut/boost
range from -10.5 dB to +12.0 dB in 1.5 dB increments. The tone control is enabled by the EnToneCtrl bit
in the Tone Config register.
Each tone control is implemented with one of two preset internal filter sets. One set is optimized for a
32 kHz sample rate, and the other is optimized for 44.1 kHz, 48 kHz, and 96 kHz sample rates. The
CS4525 automatically detects the input sample rate and chooses the appropriate filter set to apply. The
available corner frequencies are shown in tables
and TrebFc[1:0] bits in the Tone Config register.
Note that the corner frequency of each filter set scales linearly with the input sample rate.
When the internal ADC is used as the serial audio data source, the input sample rate is nominally 48 kHz
and the corresponding shelving frequency corners are available.
Referenced Control
DeEmph ..............................
Input Sample Rate
48 kHz, 96 kHz
44.1 kHz
De-Emphasis
Tone Control
32 kHz
32 kHz, 44.1 kHz, 48 kHz
Nominal Sample Rate
Register Location
“De-Emphasis Control (DeEmph)” on page 76
-10 dB
Table 2. Bass Shelving Filter Corner Frequencies
0 dB
Gain (dB)
96 kHz
Bass Fc 0
Figure 15. De-Emphasis Filter
50 Hz
48 Hz
52 Hz
Figure
0.07218 Fs
0.03609 Fs
T1=50 µs
F1
15. The de-emphasis filter is enabled and disabled by the
2
and
Bass Fc 1
100 Hz
104 Hz
96 Hz
3
0.24059 Fs
0.12030 Fs
below and are configured with the BassFc[1:0]
F2
T2 = 15 µs
Bass Fc 2
200 Hz
192 Hz
208 Hz
Frequency (Hz)
Normalized to Fs
Bass Fc 3
250 Hz
240 Hz
260 Hz
CS4525
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