CPC5622-EVAL-600R Clare, CPC5622-EVAL-600R Datasheet - Page 11

• Manufacturer Part Number: CPC5622-EVAL-600R
• Description: LITELINK III EVALUATION BOARD
• Manufacturer: Clare
• Series: LITELINK® IIIr

Specifications of CPC5622-EVAL-600R

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: CLA371

full-wave detector it will output two logic low pulses
per cycle of the ringing frequency. Hence, the
nomenclature RING2 for twice the output pulses.
The set-up of the ringing detector comparator causes
the RING output pulses to remain low for most of one
half-cycle of the ringing signal and remains high for the
entire second half-cycle of the ringing signal. For the
RING2 output, the pulses remain low during most of
both halves of the ringing cycle and returns high for
only a short period near the zero-crossing of the
ringing signal. Both of the ringing outputs remain high
during the silent interval between ringing bursts.
Hysteresis is employed in the LITELINK ringing
detector circuit to improve noise immunity.
The ringing detection threshold depends on the values
of R3 (R
C7 (C
components shown in the application circuits are
recommended for typical operation. The ringing
detection threshold can be changed according to the
following formula:
Where:
•
•
•
•
Clare Application Note AN-117
and Ring Detect Voltage Threshold
trying different component values in this circuit.
Changing the ringing detection threshold will also
change the caller ID gain and the timing of the polarity
reversal detection pulse, if used.
3.2.2 Polarity Reversal Detection in On-hook
The full-wave ringing detector in the CPC5622 makes
it possible to detect an on-hook tip and ring battery
polarity reversal using the RING2 output. When the
polarity of the battery voltage applied to tip and ring
reverses, a pulse on RING2 indicates the event. The
system logic must be able to discriminate a single
pulse of approximately 1 msec when using the
R02
V
RINGPK
R
data sheet.
RSNP
the application circuits shown in this data sheet.
C
this data sheet.
And ƒ
SNPD
SNP
SNP-
State
= C7 = C8 in the application circuits shown in
RING
TOTAL
SNPD
=
= R3 in the application circuits shown in this
), and C8 (C
⎛
⎝
750mV
---------------- -
R
is the frequency of the ringing signal.
), R6 & R44 (R
SNPD
= the total of R6, R7, R44, and R45 in
⎞
⎠
(
SNP+
R
SNP
). The value of these
TOTAL
SNP-
Customize Caller ID Gain
+
is a spreadsheet for
), R7 & R45 (R
R
SNPD
)
2
+
------------------------------------- -
(
πf
RING
SNP+
1
www.clare.com
C
SNP
),
)
2
recommended external snoop circuit components
from a valid ringing signal.
3.2.3 On-hook Caller ID Signal Reception
On-hook Caller IDentity (CID) data burst signals are
coupled through the snoop components, buffered
through LITELINK and output at the RX+ and RX-
pins.
In North America, CID data signals are typically sent
between the first and second ringing signal while in
other countries the CID information may arrive prior to
any other signalling state.
In applications that transmit CID after the first ringing
burst such as in North American, follow these steps to
receive on-hook caller ID data via the LITELINK RX
outputs:
1. Detect the first full ringing signal burst on RING
2. Monitor and process the CID data from the RX
For applications as in China and Brazil where CID may
arrive prior to ringing, follow these steps to receive
on-hook caller ID data via the LITELINK RX outputs:
1. Simultaneously monitor for CID data from the RX
2. Process the appropriate signalling data.
Note: Taking LITELINK off-hook (via the OH pin)
disconnects the snoop path from the receive outputs
and disables the ringing detector outputs RING and
RING2.
CID gain from tip and ring to RX+ and RX- is
determined by:
Where:
•
•
•
•
GAIN
R
sheet.
RSNP
the application circuits in this data sheet.
C
sheet.
and ƒ is the frequency of the CID signal
SNPD
SNP
or RING2.
outputs.
outputs and for ringing on RING or RING2.
CID
= C7 = C8 in the application circuits in this data
TOTAL
(
= R3 in the application circuits in this data
dB
)
=
= the total of R6, R7, R44, and R45 in
20
log
------------------------------------------------------------------------------------------------ -
(
R
SNP
TOTAL
+
6R
R
SNPD
SNPD
)
2
CPC5622
+
------------------------- -
(
πfC
1
SNP
11
)
2