SI3210-KTR Silicon Laboratories Inc, SI3210-KTR Datasheet - Page 48

• Manufacturer Part Number: SI3210-KTR
• Description: Telecom Line Management ICs Sgl Ch SLIC/Codec w/ DTMF Decoder
• Manufacturer: Silicon Laboratories Inc
• Type: ProSLIC Programmable CMOS SLICr

Specifications of SI3210-KTR

• Product: Telecom
• Supply Current: 4 mA
• Maximum Operating Temperature: 100 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Package / Case: TSSOP-14
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Si3210/Si3211
2.7. Audio Path
Unlike traditional SLICs, the codec function is integrated into the ProSLIC. The 16-bit codec offers programmable
gain/attenuation blocks and several loopback modes. The signal path block diagram is shown in Figure 25.
2.7.1. Transmit Path
In the transmit path, the analog signal fed by the external ac coupling capacitors is amplified by the analog transmit
amplifier, ATX, prior to the A/D converter. The gain of the ATX is user-selectable to one of mute/–3.5/0/3.5 dB
options. The main role of ATX is to coarsely adjust the signal swing to be as close as possible to the full-scale input
of the A/D converter in order to maximize the signal-to-noise ratio of the transmit path. After passing through an
anti-aliasing filter, the analog signal is processed by the A/D converter, producing an 8 kHz, 16-bit wide, linear PCM
data stream. The standard requirements for transmit path attenuation for signals above 3.4 kHz are implemented
as part of the combined decimation filter characteristic of the A/D converter. One more digital filter is available in
the transmit path: THPF. THPF implements the high-pass attenuation requirements for signals below 65 Hz. The
linear PCM data stream output from THPF is amplified by the transmit-path programmable gain amplifier, ADCG,

which can be programmed from –
dB to 6 dB. The DTMF decoder can receive the linear PCM data stream at this
point to perform the digit extraction when enabled by the user. The final step in transmit path signal processing is
the user-selectable A-law or µ-law compression, which can reduce the data stream word width to 8 bits.
Depending on the PCM_Mode register selection, every 8-bit compressed serial data word will occupy one time
slot on the PCM highway, or every 16-bit uncompressed serial data word will occupy two time slots on the PCM
highway.
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Rev. 1.5