CSP1027 Datasheet, PDF (52/64 Pages) Agere Systems – CSP1027 Voice Band Codec for Cellular Handset and Modem Applications

CSP1027 Voice Band Codec for
Cellular Handset and Modem Applications
Data Sheet
December 1999
10 Analog Characteristics and Requirements (continued)
10.2 Analog-to-Digital Path
Table 16. A/D Signal to Distortion Plus Noise Ratio
Output Signal Level
0 dBm0
–10 dBm0
–30 dBm0
–40 dBm0
–45 dBm0
–55 dBm0
Preamp
(EIGS = 0)
0.5 Vp Range
(cioc0: IRSEL = 0)
Min
Max
71
—
62
—
42
—
32
—
27
—
17
—
Preamp
(EIGS = 0)
0.16 Vp Range
(cioc0: IRSEL = 1)
Min
Max
68
—
59
—
39
—
29
—
24
—
14
—
Ext. Gain Select
Unit
(EIGS = 1)
1.578 Vp Range
Min
Max
71
—
dB
62
—
dB
42
—
dB
32
—
dB
27
—
dB
17
—
dB
Notes:
The signal to distortion plus noise ratio is from the MICIN or AUXIN input to the PCM output when EIGS = 0, and from Vin (of Figure 5 on page
7) to PCM output when EIGS = 1.
The A/D signal to distortion plus noise ratio is valid for sampling rates up to 16 kHz. For sampling rates between 16 kHz and 24 kHz, the signal
to distortion plus noise ratio is no better than 60 dB.
Table 17. A/D Relative Gain Accuracy*
Output Signal Level
Min
+3 dBm0 to –40 dBm0
–0.1
–40 dBm0 to –50 dBm0
–0.4
–50 dBm0 to –55 dBm0
–1.2
* Gain is relative to the 0 dBm0 signal level with EIGS = 0 and IRSEL = 0.
Max
0.1
0.4
1.2
Unit
dB
dB
dB
Table 18. A/D Frequency Response Relative to 1 kHz Output Level (fOS = 1 MHz and fS = 8 kHz)
Frequency
50 Hz
60 Hz
100 Hz
200 Hz
300 Hz
3000 Hz
3400 Hz
4000 Hz
4600 Hz
8000 Hz
High-Pass Filter Enabled
(HPFE = 0)
Min
Max
—
–40
—
–40
–34
–18
–12
0
–0.25
0.25
–0.25
0.25
–0.9
0.25
—
–6
—
–35
—
–45
High-Pass Filter Disabled
Unit
(HPFE = 1)
Min
Max
–0.25
0.25
dB
–0.25
0.25
dB
–0.25
0.25
dB
–0.25
0.25
dB
–0.25
0.25
dB
–0.4
0.25
dB
–0.9
0.25
dB
—
–6
dB
—
–35
dB
—
–45
dB
Note: The frequency response scales linearly with codec oversampling clock rate. Frequencies greater than 4000 Hz are affected by antialias
filtering attenuation.
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Lucent Technologies Inc.