FEBRUARY 1999 – REVISED JULY 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
TISP83121D Unidirectional P & N-Gate Protector
TISP83121D
DUAL-GATE UNIDIRECTIONAL OVERVOLTAGE PROTECTOR
Device Symbol
Overvoltage Protection for Dual-Voltage Ringing SLICs
– Programmable Protection Configurations up to ±100 V
– Typically 5 Lines Protected by:
Two TISP83121D + Diode Steering Networks
High Surge Current
– 150 A, 10/1000 µs
– 250 A, 10/700 µs
– 500 A, 8/20 µs
Pin Compatible with the LCP3121
– 50 % more surge current
– Functional Replacement in Diode Steering Applications
Small Outline Surface Mount Package
How To Order
8-SOIC Package (Top View)
Description
The TISP83121D is a dual-gate reverse-blocking unidirectional
thyristor designed for the protection of dual-voltage ringing SLICs
(Subscriber Line Interface Circuits) against overvoltages on the
telephone line caused by lightning, a.c. power contact and
induction.
The device chip is a four-layer NPNP silicon thyristor structure
which has an electrode connection to every layer. For negative
overvoltage protection the TISP83121D is used in a common anode
configuration with the voltage to be limited applied to the cathode
(K) terminal and the negative reference potential applied to the gate
1 (G1) terminal. For positive overvoltage protection the TISP83121D
is used in a common cathode configuration with the voltage to be
limited applied to the anode (A) terminal and the positive reference
potential applied to the gate 2 (G2) terminal.
MD6XAYB
1
2
3
45
6
7
8
K
A
A
K
K
K
G1
G2
For operation at the rated current values connect pins 1, 4, 5
and 8 together.
K
G1
G2
SD6XAK
A
A
The TISP83121D is a unidirectional protector and to prevent reverse bias, requires the use of a series diode between the protected line
conductor and the protector. Further, the gate reference supply voltage requires an appropriately poled series diode to prevent the supply from
being shorted when the TISP83121D crowbars.
Under low level power cross conditions the TISP83121D gate current will charge the gate reference supply. If the reference supply cannot
absorb the charging current its potential will increase, possibly to damaging levels. To avoid excessive voltage levels a clamp (zener or
avalanche breakdown diode) may be added in shunt with the supply. Alternatively, a grounded collector emitter-follower may be used to
reduce the charging current by the transistor’s HFE value.
This monolithic protection device is made with an ion-implanted epitaxial-planar technology to give a consistent protection performance and
be virtually transparent to the system in normal operation.
*RoHS Directive 2002/95/EC Jan 27 2003 including Annex
............................................... UL Recognized Component
*RoHS COMPLIANT
Device Package Carrier
TISP83121 D (8-pin Small-Outline) R (Embossed Tape Reeled) TISP83121DR-S
Order As
FEBRUARY 1999 – REVISED JULY 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Electrical Characteristics, TJ = 25 °C (Unless Otherwise Noted)
TISP83121D Unidirectional P & N-Gate Protector
Absolute Maximum Ratings
Thermal Characteristics
Parameter Test Conditions Min Typ Max Unit
IDOff-state current Vd=70V, I
G=0 1µA
IDRM Repetitive peak off-
state current Vd=V
DRM = 100 V, IG=0, 0°C to 70 °C10µA
IHHolding current IT= 1 A, di/dt = -1A/ms
TJ = 0 to 70 °C
TJ = 25 °C
TJ = 70 °C
90
60
300
mA
IRReverse current VR=0.3V 1mA
IG1T Gate G1 trigger current IT=+1A, t
p(g) =20µs +200 mA
IG2T Gate G2 trigger current IT=+1A, t
p(g) =20µs -180 mA
VG1T G1-K trigger voltage IT=+1A, t
p(g) =20µs+1.8V
VG2T G2-A trigger voltage IT=+1A, t
p(g) =20µs-1.8V
CAK Anode-cathode off-
state capacitance f=1MHz, V
d=1V rms, V
D=5V, I
G= 0 (see Note 3) 100 pF
NOTE 3: These capacitance measurements employ a three terminal capacitance bridge incorporating a guard circuit. The unmeasured
device terminals are a.c. connected to the guard terminal of the bridge.
Parameter Test Conditions Min Typ Max Unit
RθJA Junction to free air thermal resistance T
A
T TSM(900)
= 25 °C, EIA/JESD51-3 PCB,
EIA/JESD51-2 environment, I = I 105 °C/W
Rating Symbol Value Unit
Repetitive peak off-state voltage, 0 °C to 70 °CV
DRM 100 V
Non-repetitive peak on-state pulse current (see Notes 1 and 2)
ITSP A
10/1000 (GR-1089-CORE, open-circuit voltage wave shape 10/1000 150
5/310 (CCITT K20/21, open-circuit voltage wave shape 7 kV, 10/700 250
8/20 µs
µsµs)
µs)
µs)
µs
(ANSI C62.41, open-circuit voltage wave shape 1.2/50 500
Non-repetitive peak on-state current, 50 Hz, halfwave rectified sinewave, (see Notes 1 and 2)
100 ms
1 s
900 s
ITSM
22
8
3
A
Junction temperature TJ-40 to +150 °C
Storage temperature range Tstg -65 to +150 °C
NOTES: 1. Initially the protector must be in thermal equilibrium with 0 °C < TJ < 70 °C. The surge may be repeated after the device returns to
its initial conditions. For operation at the rated current value, pins 1, 4, 5 and 8 must be connected together.
2. Above 70 °C, derate linearly to zero at 150 °C lead temperature.
FEBRUARY 1999 – REVISED JULY 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Parameter Measurement Information
TISP83121D Unidirectional P & N-Gate Protector
Figure 1. Voltage-Current Characteristic
PM6XAGB
QUADRANT I
ANODE POSITIVE
SWITCHING CHARACTERISTIC
QUADRANT III
ANODE NEGATIVE
REVERSE CHARACTERISTIC
I
H
+v
-i
-v
I
D
V
R
I
R
V
DRM
+i
REFERENCE
VOLTAGE
V
GT
FEBRUARY 1999 – REVISED JULY 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
APPLICATIONS INFORMATION
TISP83121D Unidirectional P & N-Gate Protector
Multiple Line Overvoltage Protection
Figure 2 shows two TISP83121D devices protecting many lines. Line conductor positive overvoltage protection is given by the steering diode
array connected to the anode of the upper TISP83121D and the TISP83121D itself. The TISP83121D gate reference voltage is the positive
battery supply, +VBAT. The initial limiting voltage will be the sum of the voltages of the battery, the forward biased conductor diode, the gate
trigger of the TISP83121D and the forward biased reference voltage blocking diode. Typically the conductor voltage will be initially limited at
2.5 V above the +VBAT value.
Figure 2. N Line Positive and Negative Overvoltage Protection
K
A
G1 TISP83121D
G2
K
A
G1
TISP83121D
G2
0
-VE
REFERENCE
VOLTAGE
AI8XA
A
+VE
REFERENCE
VOLTAGE
LINE 1
IN
LINE N
IN
R1
T1
RN
TN
SLIC 1
SLIC N
R
R
R
R
R
R
+VBAT
-VBAT
Line conductor negative overvoltage protection is given by the diode steering array connected to the cathode of the lower TISP83121D and
the TISP83121D itself. The TISP83121D gate reference voltage is the negative battery supply, -VBAT. The initial limiting voltage will be the sum
of the voltages of the battery, the forward biased conductor diode, the gate trigger of the TISP83121D and the forward biased reference
voltage blocking diode. Typically the conductor voltage will be initially limited at 2.5 V below the -VBAT value.
When a TISP83121D crowbars and grounds all conductors of the appropriate polarity, the device current will be the sum of all the SLIC output
currents. This will usually exceed the TISP83121D holding current. To switch off the TISP83121D and restore normal operation, the grounded
condition of the SLIC output must be detected and the SLIC outputs turned off.
The 150 A rating of the TISP83121D allows a large number of lines to be protected against currents caused by lightning. For example, if a
recommendation K.20 10/700 generator was connected to all lines, together with 350 V primary protection and a series conductor resistance
(R) of 25 Ω, the maximum conductor current before the primary protection operated would be 350/25 = 14 A or 28 A per line. For a total return
current of about 150 A the number of lines would be 150/28 = 5. At this current level, 5x28 = 140 A, the generator voltage would
be140((25+25)/10+15) = 2800 V. Another limitation is long term power cross. The long term power cross capability of the TISP83121D is 3 A
peak or 2.1 A rms. If the line conductor overcurrent protection was given by a PTC thermistor which tripped at 0.2 A, the maximum number of
conductors becomes 2.1/0.2 = 10 or 5 lines.
FEBRUARY 1999 – REVISED JULY 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
TISP83121D Unidirectional P & N-Gate Protector
Battery Supply Impedance
In many designs, the battery supply voltages are generated by switching mode power supplies. This type of power supply cannot be charged
like a battery. Feeding a charging current to a switching mode power supply will usually cause the supply to stop switching and the voltage to
rise. The gate current of the TISP83121D is a charging current for the supply. To avoid the supply voltage from rising and damaging the
connected SLICs, an avalanche diode voltage clamp can be connected across the supply (Figure 3. (A)).
Another approach is to reduce the gate charging current for the supply by a transistor buffer (Figure 3. (B)). If the transistor gain was 50, a
200 mA gate current would be reduced to a supply charging current of 200/50 = 4 mA. In both cases, the dissipation in the control devices can
be substantial and power capability needs to be taken into account in device selection.
Figure 3. Reference Voltage Control by (A) Breakdown Diodes or (B) by Transistor Buffers
-VE
REFERENCE
VOLTAGE
+VE
REFERENCE
VOLTAGE
0
AI8XAB
+V
BAT
-V
BAT
(B)
K
A
G1
TISP83121D
G2
-VE
REFERENCE
VOLTAGE
+VE
REFERENCE
VOLTAGE
0
+V
BAT
-V
BAT
K
A
G1
TISP83121D
G2
K
A
G1
G2
TISP83121D
K
A
G1
G2
TISP83121D
(A)
“TISP” is a trademark of Bourns, Ltd., a Bourns Company, and is Registered in U.S. Patent and Trademark Office.
“Bourns” is a registered trademark of Bourns, Inc. in the U.S. and other countries.
