PSB4596 Siemens Semiconductor Group, PSB4596 Datasheet - Page 24

• Manufacturer Part Number: PSB4596
• Description: Analog Line Interface Solution ALIS
• Manufacturer: Siemens Semiconductor Group

4.3.2
The analog signal is converted to a 1-bit data stream in the ADC. After decimation in
hardware filters, the remaining processing is done in the digital filter structure (in RLM):
bandpass filtering to select the ringing frequency, and integration to determine if the
amount of energy in-band has exceeded the threshold for a valid ring signal. The
bandpass parameters and threshold are programmable.
Ringing is detected in this path. The digital input is bandpass filtered, integrated and
compared to a threshold to determine if a ringing signal has occurred. The threshold and
bandpass filters are programmable. The result of this operation can be monitored by
reading the RMR bit (see “CR1 Configuration Register 1 (Dialing)” on page 40).
4.3.3
A loop is available to generate the Ring-termination impedance (RIM).
4.3.3.1 Test Features
There are three loopbacks on ALIS-D to test interfaces:
- Host interface: loopback from the PCM interface (just inside ALIS-D)
- Caller ID interface: loopback from Caller ID input to capacitor interface
- Capacitor interface: loopback through different parts of the capacitor interface
There are two loopbacks on ALIS-A:
- Tip/ring interface: loopback from the tip/ring, before the ADC
- Codec: loopback from the tip/ring, after the codec
Semiconductor Group
Ring-Level Metering (RLM) Path
Loops
24
Analog Line Interface Solution
PSB 4595 / PSB 4596
ALIS Implementation
Data Sheet 06.98