PSB4860HV4.1 Lantiq, PSB4860HV4.1 Datasheet - Page 53

• Manufacturer Part Number: PSB4860HV4.1
• Manufacturer: Lantiq

Specifications of PSB4860HV4.1

• Lead Free Status / Rohs Status: Supplier Unconfirmed

PSB 4860
2.1.9
CPT Detector
The selected signal is monitored continuously for a call progress tone. The CPT detector
consists of a band-pass and an optional timing checker (figure 28).
Band-pass
I
SCI (Status)
1
300-640 Hz
Timing
Checker
Figure 28 CPT Detector - Block Diagram
The CPT detector can be used in two modes: raw and cooked. In raw mode, the
occurrence of a signal within the frequency range, time and energy limits is directly
reported. The timing checker is bypassed and therefore the does not interpret the length
or any interval of the signal.
In cooked mode, the number and duration of signal bursts are interpreted by the timing
checker. A signal burst followed by a gap is called a cycle. Cooked mode requires a
minimum of two cycles. The CPT flag is set with the first burst after the programmed
number of cycles has been detected. The CPT flag remains set until the unit is disabled
or speech is detected, even if the conditions are not met anymore. In this mode the CPT
is modeled as a sequence of identical bursts separated by gaps with identical length.
The can be programmed to accept a range for both the burst and the gap. It is also
possible to specify a maximum aberration of two consecutive bursts and gaps. Figure 29
shows the parameters for a single cycle (burst and gap).
t
Bmax
t
Bmin
t
Gmin
t
Gmax
Figure 29 CPT Detector - Cooked Mode
The status bit is defined as follows:
Data Sheet
53
2000-01-14