psb21381 Infineon Technologies Corporation, psb21381 Datasheet - Page 140

• Manufacturer Part Number: psb21381
• Description: Siemens Codec With S/t Transceiver
• Manufacturer: Infineon Technologies Corporation

Data Sheet
4.3.4
A programmable tone filter can be switched in the tone signal path by setting the ETF
(Enable Tone Filter) bit. The tone filter contains a programmable equalizer and a
saturation amplifier (see figure Chapter 75).
A generated square-wave or trapezoid signal can be converted by the equalizer into a
sine-wave signal. The equalizer is realized as a band-pass filter. The filter parameters
(center frequency, bandwidth and attenuation of the stop-band) are programmable by
the CRAM parameters listed in Table Chapter 19
Table 19 CRAM Parameters of the Tone Filter
Parameter
A1
A2
K
GE
A maximum attenuation of the first harmonic frequency of 50 dB is possible. Figure
Chapter 77 shall illustrate the equalizer parameters.
Tone Filter
# of CRAM
Bytes
1
1
1
1
Range
200 Hz to 4 kHz
0 to – 1
0 to 54 dB
+ 12 to – 12 dB
130
Comment
Center frequency
Determines with A1 and K the
bandwidth. The closer A2 comes
to -1, the smaller the bandwidth.
Attenuation of the stop-band
Saturation amplification
PSB 21381/2
PSB 21383/4
2001-03-12
Codec