CPC5601
2.1 Application Circuit Configurations
2.2.2 LITELINK III
Figure 4 shows LITELINK II in circuit designed to use
the optical snoop circuit in the CPC5601 for ring
detection. Figure 5 shows LITELINK III in a circuit that
uses the LITELINK snoop circuit ring detection and
display feature (caller ID) signal processing. Note that
either generation of LITELINK can be used with either
signal monitoring scheme. Using the optical path on
the CPC5601 for ring detect precludes on-hook dis-
play feature signal processing.
The networks connected to outputs b1 and b3 provide
selectable telephone line AC termination depending
on which network is switched in place of R
(see the
ZNT
appropriate LITELINK data sheet and the application
note Understanding LITELINK for more information).
The resistor connected to output b2 provides the
required bias current for North American applications.
In North American applications, turn outputs b1 and
b2 on, and turn output b3 off to switch in the required
600 Ω AC termination. For European applications, turn
outputs b1 and b2 off, and output b3 on to switch in the
complex AC termination network.
2.2 AC Termination
2.2.1 LITELINK II
The networks connected to outputs b1, b2, b3 and b4
provide selectable telephone line AC termination
depending on which network is switched in place of
2.3 LITELINK III Gain
Turning output 5 on adds attenuation to the receive
path, which is required for the complex termination.
Asserting the MODE pin on LITELINK III corrects for
the added attenuation.
R
(see the appropriate LITELINK data sheet and
ZNT
the application note Understanding LITELINK for more
information).
In North American applications, turn outputs b1 and
b2 on, and turn outputs b3 and b4 off to switch in the
required 600 Ω AC termination. For European applica-
tions, turn outputs b1 and b2 off, and outputs b3 and
b4 on to switch in the complex AC termination net-
work.
2.4 Current Limiting
Clare recommends using the default value for RZDC
to set the loop-current limit to 133 mA. You can, if
required, adjust the current limit level by adding R73
and using output b6 to switch this value in parallel with
RZDC. See the appropriate LITELINK datasheet for
more information on setting loop-current limits.
2.5 Figure 4 Part List
Qty.
Reference
Value
CPC561x LITELINK II
CPC5601 Auxiliary Programmable Driver
Suppliers
1
1
1
1
1
1
2
1
1
U1
U4
Q1
Q2
Clare, Inc.
CPC5602C N-Channel Depletion-Mode FET
MMBT4126 PNP bipolar transistor
S1ZB60 or DB104 Bridge Rectifier
1N914
Fairchild
DB1
D1
Sindengen Co., Diodes, Inc.
Z1, Z2
SP1
FB1
10V Zener Diode
P3100SB Sidactor
Teccor, TI, ST Microelectronics
Murata BLM11A601S or similar
600 Ω, 200 mA ferrite bead
8
www.clare.com
R3.0
CLARE [ CLARE ]
