1/6
Application Specific Discretes
ASDTM
SSRP105B1
Where asymmetrical protection against lightning
strikes and other transient overvoltages is required :
s
Solid-State relays
s
SLIC with integrated ring generator
MAIN APPLICATIONS
SO-8
The SSRP105B1 is a dual asymmetrical transient
voltage
suppressor
designed
to
protect
a
solid-state ring relay or SLICs with integrated ring
generator from overvoltages.
The asymmetrical protection configuration is
necessary to allow the use of all different types of
ringing schemes.
DESCRIPTION
FUNCTIONAL DIAGRAM
DUAL ASYMMETRICAL OVERVOLTAGE
PROTECTION FOR TELECOM LINE
October 2002 - Ed: 1A
1
2
3
4
5
6
8
GND
NC
NC
7
TIP
RING
GND
GND
GND
TM: ASD is trademarks of STMicroelectronics.
Peak Surge
Voltage
(V)
Voltage
Waveform
(s)
Current
Waveform
(s)
Required
Peak
current
(A)
Min. serial
resistor to meet
standards
(
)
ITU-T K20 / K21
1500
10/700
5/310
38
-
VDE0433
2000
10/700
5/310
50
-
IEC61000-4-5
Level 3
Level 4
10/700
1.2/50
5/310
8/20
50
100
-
-
FCC Part 68
1500
800
10/160
10/560
10/160
10/560
200
100
18
10
BELLCORE
GR1089 First level
2500
1000
2/10
10/1000
2/10
10/1000
500
100
10
19
COMPLY WITH THE FOLLOWING STANDARDS
s
Dual bi-directional asymmetrical protection
Stand-off voltages:
q
Between Line and Ground
+105V for positive voltages
-180V for negative voltages
q
Between Line and Line
+180V for positive voltages
-180V for negative voltages
s
Peak pulse current: I
PP
= 50A (5/310s)
s
Holding current:
q
I
H+
= 100mA
q
I
H-
= 150mA
FEATURES
SSRP105B1
2/6
Fig. 1: Topology of the classical line card protection.
APPLICATION INFORMATION
Fig. 2: Classical use of the SSRP105B1.
The classical line card requires protection before the
ring relay and a second one for the SLIC (
figure 1).
The use of new SLICs with integrated ring
generator or board based on solid-state ring relay
suppresses this second protection (
figure 2).
Then, the only remaining stage, located between
the line and the ring relay, has to optimize the
protection.
The classical symmetrical first stage protector
becomes not sufficient to avoid any circuit
destruction during surges.
The SSRP105B1 device takes into account this
fact and is based on asymmetrical voltage
characteristics (
figure 3a). The ring signal being
shifted
back
by
the
battery
voltage,
the
SSRP105B1 negative breakover value V
BO-
is
greater than the positive one V
BO+
. This point
guarantees a protection operation very close to the
peak of the normal operating voltage without any
disturbance of the ring signal.
Fig. 3: SSRP105B1 electrical characteristics.
V
BO-
I
V
V
BO+
a: Line to ground characteristics.
V
BO-
I
V
V
BO+
b: Line to line characteristics.
In addition with the 2 crowbar functions which
perform the protection of both TIP and RING lines
versus ground, a third cell assumes the differential
mode protection of the SLIC. The breakover
voltage values of this third cell are the same for
both
positive
and
negative
parts
of
the
characteristics and are equivalent to the negative
breakover voltage value of the TIP and RING lines
versus GND cells (
figure 3b).
PTC
PTC
R
R
SLIC
(*)
TIP
RING
SSRP105B1
(*) SLIC with integrated ring generator or Solid-State Relay
LINE
1st
stage
2nd
stage
PTC
PTC
R
R
SLIC
Ring generator
V
RING
V
RINGBAT
TIP
RING
SSRP105B1
3/6
Symbol
Parameter
Value
Unit
I
PP
Peak pulse current (see note 1)
10 / 1000 s
10 / 560s
5 / 310s
10 / 160s
8 / 20s
2 / 10s
35
45
50
60
120
175
A
I
TSM
Non repetitive surge peak on-state current
(F=50Hz)
tp = 0.2 s
tp = 5 s
tp = 15 min.
8.5
4.5
2.5
A
T
op
Operating temperature range
0 to + 70
C
T
stg
T
j
Storage temperature range
Maximum operating junction temperature
- 55 to + 150
+ 150
C
C
T
L
Maximum lead temperature for soldering during 10s
260
C
ABSOLUTE MAXIMUM RATINGS (T
amb
= 25C)
Note 1 : Pulse waveform :
10/1000s
t
r
=10s
t
p
=1000s
10/560s
t
r
=10s
t
p
=560s
5/310s
t
r
=5s
t
p
=310s
10/160s
t
r
=10s
t
p
=160s
8/20s
t
r
=8s
t
p
=20s
2/10s
t
r
=2s
t
p
=10s
100
50
% I
PP
t
t
r
p
0
t
Symbol
Parameter
Value
Unit
R
th (j-a)
Junction to ambient
170
C/W
THERMAL RESISTANCE
I
V
I
PP
I
H
I
R
V
R
V
BR
V
BO
Symbol
Parameter
V
R
Stand-off voltage
I
R
Leakage current at stand-off voltage
V
BR
Breakdown voltage
V
BO
Breakover voltage
I
H
Holding current
I
BO
Breakover current
I
PP
Peak pulse current
C
Capacitance
ELECTRICAL CHARACTERISTICS (T
amb
= 25C)
SSRP105B1
4/6
Symbol
Parameter
Test conditions (note 1)
Min.
Typ.
Max.
Unit
V
BO
Breakover voltage
(note 2)
Positive voltage
Negative voltage
. 50Hz
. 10/700s
. 50Hz
. 10/700s
165
165
225
225
V
I
H
Holding current
Positive polarity
Negative polarity
100
150
mA
I
R
Leakage current
(note 3)
V
R
= +105 V
V
R
= - 180 V
10
10
A
C
Capacitance
F = 1MHz, V
RMS
= 1V, V
R(T/G)
= -5V
F = 1MHz, V
RMS
= 1V, V
R(T/G)
= -50V
30
16
pF
ELECTRICAL CHARACTERISTICS between TIP and GND, RING and GND (T
amb
=25C)
Symbol
Parameter
Test conditions
Min
Max
Unit
I
R
Leakage current (note 3)
V
R
= +180 V
V
R
= - 180 V
10
10
A
Note 1:
Positive voltage means between T and G, or between R and G.
Negative voltage means between G and T, or between G and R.
Note 2:
See test circuit for V
BO
parameters
Note 3:
I
R
measured at V
R
guarantees V
BR
> V
R
ELECTRICAL CHARACTERISTICS between TIP and RING (T
amb
=25C)
IH(Tamb)/IH(Tamb=25C)
Tamb(C)
0
0.2
0.4
0.6
0.8
1
1.2
0
20
40
60
80
Fig. 4: Relative variation of holding current versus
junction temperature.
0
5
10
15
20
25
0.01
0.1
1
10
100
1000
F= 50Hz
ITSM(A)
tp(s)
Fig. 5: Non-repetitive peak on-state current versus
overload duration (Tj initial = +25C)..
1
10
100
1
10
100
1000
Tj= 25C
F= 1MHz
Vrms= 1V
TIPor RING(+) / GND(-)
GND(+) / TIP or RING(-)
C(pF)
VR(V)
Fig. 6: Capacitance versus applied reverse
voltages (typical values).
SSRP105B1
5/6
FUNCTION HOLDING CURRENT (I
H
) TEST CIRCUIT (GO-NO GO TEST)
R
V
BAT
= - 48 V
Surge generator
D.U.T.
This is a GO-NOGO test which allows to confirm the holding current (I
H
) level in a functional test
circuit.
TEST PROCEDURE :
1) Adjust the current level at the I
H
value by short circuiting the D.U.T.
2) Fire the D.U.T with a surge Current : Ipp = 10A , 10/1000s.
3) The D.U.T will come back off-state within 50 ms max.
Pulse (s)
V
p
C
1
C
2
L
R
1
R
2
R
3
R
4
I
PP
R
p
t
r
t
p
(V)
(F)
(nF)
(H)
(
)
(
)
(
)
(
)
(A)
(
)
10
700
1000
20
200
0
50
15
25
25
38
0
1.2
50
1500
1
33
0
76
13
25
25
30
10
2
10
2500
10
0
1.1
1.3
0
3
3
38
62
V
P
L
TIP
RING
GND
C
1
R
1
R
4
R
3
R
2
C
2
TEST CIRCUIT FOR V
BO
PARAMETERS:
SSRP 105 B 1 RL
SOLID STATE RELAY
PROTECTION
STAND-OFF VOLTAGE
PACKAGE:
1 = SO-8 Plastic
PACKAGING:
RL = Tape and Reel
= Tube
ORDER CODE
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