®
LCP1511D
PROGRAMMABLE TRANSIENT VOLTAGE
SUPPRESSOR FOR SLIC PROTECTION
Application Specific Discretes
A.S.D.™
FEATURES
DUAL PROGRAMMABLE TRANSIENT SUP-
PRESSOR.
WIDE NEGATIVE FIRING VOLTAGE RANGE :
V
MGL
= -80V max.
LOW DYNAMIC SWITCHING VOLTAGES :
V
FP
and V
DGL
.
LOW GATE TRIGGERING CURRENT :
I
GT
= 5mA max.
PEAK PULSE CURRENT :
I
PP
= 30A for 10/1000µs surge.
HOLDING CURRENT :
I
H
= 150mA.
DESCRIPTION
This device has been especially designed to pro-
tect subscriber line card interfaces (SLIC) against
transient overvoltages.
Positive overloads are clipped with 2 diodes.
Negative surges are suppressed by 2 thyristors,
their breakdown voltage being referenced to
-V
BAT
through the gate.
This component presents a very low gate trigge-
ring current (I
GT
) in order to reduce the current con-
sumption on printed circuit board during the firing
phase.
A particular attention has beengiven to the internal
wire bonding. The ”4-point” configuration ensures
reliable protection, eliminating the overvoltage in-
troduced by the parasitic inductances of the wiring
(Ldi/dt), especially for very fast transients.
COMPLIESWITHTHE FOLLOWINGSTANDARDS :
CCITT K20 :
VDE 0433 :
VDE 0878 :
I3124 :
FCC part 68 :
10/700µs
5/310µs
10/700µs
5/310µs
1.2/50µs
1/20µs
0.5/700µs
0.2/310µs
2/10µs
2/10µs
1kV
25A
2kV
38A (*)
1.5kV
40A
1kV
25A
2.5kV
170A (*)
2.5kV
170A (*)
SO8
SCHEMATIC DIAGRAM
TIP 1
GATE 2
NC 3
RING 4
8 TIP
7 GND
6 GND
5 RING
BELLCORE
TR-NWT-001089 :
2/10µs
2/10µs
(*) with series resistors or PTC.
February 1998
Ed: 3
TM: ASD is trademarks of SGS-THOMSON Microelectronics.
1/7
LCP1511D
ABSOLUTE MAXIMUM RATINGS
(T
amb
= 25
°C)
Symbol
I
PP
Peak pulse current
(see note 1)
Non repetitive surge peak on-state current
(F = 50Hz)
Maximum gate current (half sine wave tp = 10ms)
Maximum voltage LINE / GROUND
Maximum voltage GATE / LINE
Storage temperature range
Maximum junction temperature
Maximum lead temperature for soldering during 10s
Parameter
10/1000µs
5/310µs
2/10µs
t
p
= 10ms
t = 1s
Value
30
38
170
8
3.5
2
-100
-80
- 55 to + 150
150
260
Unit
A
I
TSM
I
GSM
V
MLG
V
MGL
T
stg
T
j
T
L
A
A
V
°C
°C
Note 1 :
Pulse waveform :
10/1000µs
tr=10µs
5/310µs
tr=5µs
2/10
µ
s
tr=2
µ
s
tp=1000µs
tp=310µs
tp=10
µ
s
% I
PP
100
50
0
t
r
t
p
t
THERMAL RESISTANCE
Symbol
R
th (j-a)
Junction to ambient
Parameter
Value
170
Unit
°C/W
ELECTRICAL CHARACTERISTICS
(T
amb
= 25°C)
Symbol
I
GT
I
H
I
RM
I
RG
V
RM
V
F
V
GT
V
FP
V
DGL
V
GATE
V
LG
C
2/7
Parameter
Gate triggering current
Holding current
Reverse leakage current LINE/GND
Reverse leakage current GATE/LINE
Reverse voltage LINE/GND
Forward drop voltage LINE/GND
Gate triggering voltage
Peak forward voltage LINE/GND
Dynamic switching voltage GATE/LINE
GATE/GND voltage
LINE/GND voltage
Off-state capacitance LINE/GND
V
V
GATE RM
I
F
I
V
LG
F
I
RM
V
I
H
I
PP
LCP1511D
1 - PARAMETERS RELATED TO THE DIODE LINE/GND
(T
amb
= 25
°C)
Symbol
V
F
V
FP
I
F
=5A
10/700µs
1.2/50µs
2/10µs
1.5kV
1.5kV
2.5kV
Test conditions
t
p
=500µs
R
p
=10Ω
R
p
=10Ω
R
p
=62Ω
(see note 1)
Maximum
3
5
7
12
Unit
V
V
Note 1 :
See test circuit 2 for V
FP
; R
p
is the protection resistor located on the line card.
2 - PARAMETERS RELATED TO THE PROTECTION THYRISTOR
(T
amb
= 25°C)
Symbol
I
GT
I
H
V
GT
I
RG
V
DGL
V
GND/LINE
= -48V
V
GATE
=-48V (see note 2)
at I
GT
T
c
=25°C
T
c
=70°C
V
RG
=-75V
V
RG
=-75V
I
PP
=30A
I
PP
=30A
I
PP
=38A
Test conditions
Min.
0.2
150
2.5
5
50
10
20
25
Max.
5
Unit
mA
mA
V
µA
VGATE= -48V (see note 3)
10/700µs 1.5kV
Rp=10Ω
1.2/50µs 1.5kV
Rp=10Ω
2/10µs
2.5kV
Rp=62Ω
V
Note 2 :
Note 3 :
See the functional holding current (I
H
) test circuit 2.
See test circuit 1 for V
DGL
.
The oscillations with a time duration lower than 50ns are not taken into account.
3 - PARAMETERS RELATED TO DIODE AND PROTECTION THYRISTOR
(T
amb
= 25
°C)
Symbol
I
RM
C
T
c
=25°C
T
c
=70°C
V
R
=-3V
V
R
=-48V
Test conditions
V
GATE/LINE
= -1V
V
GATE/LINE
= -1V
F=1MHz
F=1MHz
V
RM
=-75V
V
RM
=-75V
Maximum
5
50
100
50
Unit
µA
pF
APPLICATION NOTE
TIP
1
IN
OUT
8
TIP
GATE
2
7
GND
In order to take advantageof the ”4 point” structure
of the LCP, the TIP and RING lines go across the
device. In such case, the device will eliminate the
overvoltages generated by the parasitic induc-
tances of the wiring (Ldi/dt), especially for very fast
transients.
NC
3
6
RING
4
IN
OUT
5
RING
3/7
LCP1511D
FUNCTIONAL HOLDING CURRENT (I
H
) TEST CIRCUIT 1 : GO-NO GO TEST
R
P
D .T
.U .
V
BA
=
T
-
48V
Surge
generator
This is a GO-NO GO test which allows to confirm the holding current (I
H
) level in a functional test circuit.
TEST PROCEDURE :
- Adjust the current level at the I
H
value by short circuiting the D.U.T.
- Fire the D.U.T. with a surge current : I
PP
= 10A, 10/1000µs.
- The D.U.T. will come back to the off-state within a duration of 50ms max.
TEST CIRCUIT 2 FOR V
FP
AND V
DGL
PARAMETERS
(V is defined in unload condition)
P
R
4
TIP
R
2
RING
R
3
L
V
P
C
1
R
1
C
2
G ND
Pulse (µs)
t
r
10
1.2
2
t
p
700
50
10
V
p
(V)
1500
1500
2500
C
1
(
µ
F)
20
1
10
C
2
(nF)
200
33
0
L
(
µ
H)
0
0
1.1
R
1
(
Ω
)
50
76
1.3
R
2
(
Ω
)
15
13
0
R
3
(
Ω
)
25
25
3
R
4
(
Ω
)
25
25
3
I
PP
(A)
30
30
38
R
p
(
Ω
)
10
10
62
4/7
LCP1511D
FUNCTIONAL DESCRIPTION
LINE A PROTECTION :
– For positive surges versus GND, the diode D1
will conduct.
– For negative surges versus GND, the protection
device P1 will trigger at a voltage fixed by the
-V
BAT
reference.
LINE B PROTECTION :
– For surges on line B, the operating mode is the
same, D2 or P2 is activated.
It is recommended to add a capacitor (C=220nF)
close to the gate of the LCP, in order to speed up
the triggering.
LINE A
D
1
P
1
TIP
- V
BAT
P
2
D
2
LINE B
RING
C
Surge peak current versus overload duration.
I
TSM
(A)
10
9
8
7
6
5
4
3
2
1
0
1E-2
1E-1
1E+0
F=50H z
Tj initial=25°C
t(s)
1E+1
1E+2
1E+3
5/7
京公网安备 11010802033920号
EEWORLD
