hc5523 Intersil Corporation, hc5523 Datasheet - Page 15

• Manufacturer Part Number: hc5523
• Description: Lssgr/tr57 Co/loop Carrier Slic With Low Power Standby
• Manufacturer: Intersil Corporation

temperature of the die cools down by about 20
will return back to its normal operating mode, providing the
fault condition has been removed.
Surge Voltage Protection
The HC5523 must be protected against surge voltages and
power crosses. Refer to “Maximum Ratings” TIPX and
RINGX terminals for maximum allowable transient tip and
ring voltages. The protection circuit shown in Figure 21
utilizes diodes together with a clamping device to protect tip
and ring against high voltage transients.
SLIC Operating States
The fuse resistors (R
nondestructive power dissipaters during surge and fuses
when the line in exposed to a power cross.
Power-Up Sequence
The HC5523 has no required power-up sequence. This is a
result of the Dielectrically Isolated (DI) process used in the
fabrication of the part. By using the DI process, care is no
longer required to insure that the substrate be kept at the
most negative potential as with junction isolated ICs.
Printed Circuit Board Layout
Care in the printed circuit board layout is essential for proper
operation. All connections to the RSN pin should be made as
close to the device pin as possible, to limit the interference
that might be injected into the RSN terminal. It is good
practice to surround the RSN pin with a ground plane.
E0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
E1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
F
) serve a dual purpose of being
C1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
15
C2
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Open Circuit
Active
Ringing
Standby
Open Circuit
Active
Ringing
Standby
Open Circuit
Active
Ringing
Standby
Open Circuit
Active
Ringing
Standby
SLIC OPERATING STATE
o
C. The SLIC
TABLE 1. LOGIC TRUTH TABLE
HC5523
Positive transients on tip or ring are clamped to within a
couple of volts above ground via diodes D
normal operating conditions D
and out of the circuit.
Negative transients on tip and ring are clamped to within a
couple of volts below ground via diodes D
help of a Surgector. The Surgector is required to block
conduction through diodes D
operating conditions and allows negative surges to be
returned to system ground.
The analog and digital grounds should be tied together at the
device.
Notes
2. Overload Level (Two-Wire port) - The overload level is speci-
3. Longitudinal Impedance - The longitudinal impedance is
4. Longitudinal Current Limit (Off-Hook Active) - Off-Hook
No Active Detector
Ground Key Detector
No Active Detector
Ground Key Detector
No Active Detector
Loop Current Detector
Ring Trip Detector
Loop Current Detector
No Active Detector
Ground Key Detector
No Active Detector
Ground Key Detector
No Active Detector
Loop Current Detector
Ring Trip Detector
Loop Current Detector
fied at the 2-wire port (V
receive port (E
amplitude of E
ence Figure 1.
computed using the following equations, where TIP and RING
voltages are referenced to ground. L
A
(TIP) L
(RING) L
where: E
(Active, C
by increasing the amplitude of E
T
are defined in Figure 2.
ACTIVE DETECTOR
ZT
ZR
L
= V
1
= 1V
= 1, C
= V
T
/A
RX
RX
RMS
R
T
/A
). I
2
until 1% THD is measured at V
R
= 0) longitudinal current limit is determined
(0Hz to 100Hz)
DCMET
TR0
) with the signal source at the 4-wire
3
= 30mA, R
1
and D
and D
L
(Figure 3A) until the 2-wire
Logic Level High
Ground Key Status
Logic Level High
Ground Key Status
Logic Level High
Loop Current Status
Ring Trip Status
Loop Current Status
4
ZT
2
under normal
Logic Level High
SG
are reverse biased
, L
DET OUTPUT
1
ZR
3
= 4kΩ, increase the
and D
and D
, V
T
, V
TRO
2
4
. Under
R
with the
, A
. Refer-
R
and