
V1.8 October 2006
Data Sheet
sending Caller Line Identification (CLI) information or
for other “no ring” calls.
The Ag1160 will provide on hook transmission with a
high impedance on Tip/Ring or specific loads are
demanded by Network Operators.
3.0 Switch Hook Detect Level
When the subscriber goes “off-hook” loop current will
begin to flow. If this current is above the detection
threshold (10mA) the switch hook output, SHK, will
switch to a logic 1. It is recommended that software or
hardware de-bouncing of the switch hook signal is
used. This is to avoid short pulses which can cause a
false switch hook output, triggering the incorrect
system response.
During loop disconnect dialling, SHK will pulse
between logic 1 and logic 0 to indicate the digits being
dialled. Again it is recommended that software de-
bouncing is used to avoid false detection of digits.
4.0 Protection of the Ag1160 SLIC
4.1 Thermal Protection
Should the SLIC be operated incorrectly, for example
by accidentally shorting Tip and Ring to each other or
to ground, there is a danger the power dissipation
Ag1160
5V RINGING SLIC
Silver Telecom 2006
Page 6
could exceed the 1.6W maximum rating. In this case a
thermal cut-off will ensure the device gradually powers
down safely by reducing the loop current. Once the
problem has been corrected the loop current will return
to its normal level.
This feature means that the SLIC can be used even
when a thermal overload has occurred.
4.2 Lightning and Power Cross Protection.
It is usual for the Ag1160 to be used in “on-premise”
applications, such as SOHO, CTI and VoIP. In this
case power cross and lightning protection is not
required, however in most ‘off-premise’ applications, a
subscriber circuit will be required to withstand over
voltage conditions which could be caused by lightning
or overhead power cables striking the telephone
cables. It is therefore normal in “off-premise”
applications to provide primary and secondary
protection circuits to prevent damage to the SLIC.
The Ag1160 has been designed to be able to use low
cost protection components and a typical circuit is
shown in Figure 5. This circuit is suitable for most “on-
premise” applications.
With some additional components, the Ag1160 will
meet UL1459 and 1950 requirements: a series element
should be added - a combination of a fuse (e.g.
350mA, Bussman C515 or Littelfuse 220003) and a
Figure 4: Typical Connection Diagram.
Components
C1, C3 = 100nF
C2 = 220uF, 10V, RubyconZL
C4 = 100uF, 6.3V
C5 = 220nF, 16V
R1, R3 = 10k
R2 = 10
TIP
℡
RING
Protection
+5V
C1
Ag1160
F/R
SHK
V
OUT
V
IN
RING
TIP
+5V
PWR
GND
PWR
R1
RM
C5
CAP
T E L E C O M
Silver
C2
+
R2
+5V
A
GND
A
C3
+5V
+
C4
R3
LO
PD