MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
TISP70xxF3 (LV) Overvoltage Protector Series
TISP7072F3,TISP7082F3
LOW-VOLTAGE TRIPLE ELEMENT BIDIRECTIONAL
THYRISTOR OVERVOLTAGE PROTECTORS
Device Symbol
Device VDRM
V
V(BO)
V
‘7072F3 58 72
‘7082F3 66 82
Waveshape Standard ITSP
A
2/10 GR-1089-CORE 85
8/20 IEC 61000-4-5 80
10/160 FCC Part 68 65
10/700 FCC Part 68
ITU-T K.20/21 50
10/560 FCC Part 68 45
10/1000 GR-1089-CORE 40
Patented Ion-Implanted Breakdown Region
- Precise DC and Dynamic Voltages
Planar Passivated Junctions
Low Off-State Current..................................<10 µA
Rated for International Surge Wave Shapes
- Single and Simultaneous Impulses
How To Order
D Package (Top View)
Description
The TISP7xxxF3 series are 3-point overvoltage protectors
designed for protecting against metallic (differential mode) and
simultaneous longitudinal (common mode) surges. Each terminal
pair has the same voltage limiting values and surge current
capability. This terminal pair surge capability ensures that the
protector can meet the simultaneous longitudinal surge
requirement which is typically twice the metallic surge
requirement.
Each terminal pair has a symmetrical voltage-triggered
thyristor characteristic. Overvoltages are initially clipped by
breakdown clamping until the voltage rises to the breakover
level, which causes the device to crowbar into a low-voltage on
state. This low-voltage on state causes the current resulting from
the overvoltage to be safely diverted through the device.
.............................................UL Recognized Component
1
2
3
45
6
7
8
G
NU
NU
G
NC
T
R
NC
G
TR
SD7XAB
Terminals T, R and G correspond to the
alternative line designators of A, B and C
*RoHS Directive 2002/95/EC Jan 27 2003 including Annex
*RoHS COMPLIANT
NC - No internal connection.
NU - Non-usable; no external electrical connection should be
made to these pins.
Specified ratings require connection of pins 5 and 8.
Device Package Carrier
TISP70xxF3 D, Small-Outline Tape and Reel TISP70xxF3DR-S
Order As
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Description (continued)
TISP70xxF3 (LV) Overvoltage Protector Series
Absolute Maximum Ratings, TA = 25 °C (Unless Otherwise Noted)
The high crowbar holding current helps prevent d.c. latchup as the diverted current subsides. These protectors are guaranteed to voltage limit
and withstand the listed lightning surges in both polarities.
These low voltage devices are guaranteed to suppress and withstand the listed international lightning surges on any terminal pair. Nine similar
devices with working voltages from 100 V to 275 V are detailed in the TISP7125F3 thru TISP7380F3 data sheet.
Rating Symbol Value Unit
Repetitive peak off-state voltage, 0 °C < TA < 70 °C
‘7072F3
‘7082F3
VDRM 58
66
V
Non-repetitive peak on-state pulse current (see Notes 1 and 2)
IPPSM A
1/2 (Gas tube differential transient, 1/2 voltage wave shape) 240
2/10 (Telcordia GR-1089-CORE, 2/10 voltage wave shape) 85
1/20 (ITU-T K.22, 1.2/50 voltage wave shape, 25 Ω resistor) 45
8/20 (IEC 61000-4-5, combination wave generator, 1.2/50 voltage wave shape) 80
10/160 (FCC Part 68, 10/160 voltage wave shape) 65
4/250 (ITU-T K.20/21, 10/700 voltage wave shape, simultaneous) 60
0.2/310 (CNET I 31-24, 0.5/700 voltage wave shape) 50
5/310 (ITU-T K.20/21, 10/700 voltage wave shape, single) 50
5/320 (FCC Part 68, 9/720 voltage wave shape, single) 50
10/560 (FCC Part 68, 10/560 voltage wave shape) 45
10/1000 (Telcordia GR-1089-CORE, 10/1000 voltage wave shape) 40
Non-repetitive peak on-state current, 0 °C < TA < 70 °C (see Notes 1 and 3)
50 Hz, 1 s ITSM 4.3 A
Initial rate of rise of on-state current, Linear current ramp, Maximum ramp value < 38 A diT/dt 250 A/µs
Junction temperature TJ-65 to +150 °C
Storage temperature range Tstg -65 to +150 °C
NOTES: 1. Initially, the TISP® device must be in thermal equilibrium at the specified TA. The surge may be repeated after the TISP® device
ireturns to its nitial conditions. The rated current values may be applied singly either to the R to G or to the T to G or to the T
Additionally, both R to G and T to G may have their rated current values applied simultaneously (in this case
current will be twice the above rated current values).
2. See Thermal Information for derated IPPSM values 0 °C < TA < 70 °C and Applications Information for details on wave shapes.
3. Above 70 °C, derate ITSM linearly to zero at 150 °C lead temperature.
to R terminals. .
the total G terminal
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Electrical Characteristics for all Terminal Pairs, TA = 25 °C (Unless Otherwise Noted)
Parameter Test Conditions Min Typ Max Unit
IDRM Repetitive peak off-
state current VD=V
DRM, 0 °C<T
A<70°C±10 µA
V(BO) Breakover voltage dv/dt = ±250 V/ms, RSOURCE = 300 Ω‘7072F3
‘7082F3
±72
±82 V
V(BO) Impulse breakover
voltage
dv/dt ≤±1000 V/µs, Linear voltage ramp,
Maximum ramp value = ±500 V
di/dt = ±20 A/µs, Linear current ramp,
Maximum ramp value = ±10 A
‘7072F3
‘7082F3
±90
±100 V
I(BO) Breakover current dv/dt = ±250 V/ms, RSOURCE = 300 Ω±0.1 ±0.8 A
VTOn-state voltage IT=±5A, t
W= 100 µs±5V
IHHolding current IT=±5A, di/dt=-/+30mA/ms ±0.15 A
dv/dt Critical rate of rise of
off-state voltage Linear voltage ramp, Maximum ramp value < 0.85VDRM ±5kV/µs
IDOff-state current VD=±50 V ±10 µA
Coff Off-state capacitance
f=1MHz, V
d=1V rms, V
D=0
f=1MHz, V
d=1V rms, V
D=-1V
f=1MHz, V
d=1V rms, V
D=-2V
f=1MHz, V
d=1V rms, V
D=-5V
f=1MHz, V
d=1V rms, V
D=-50V
f=1MHz, V
d=1V rms, V
DTR =0
(see Note 4)
53
56
51
43
25
29
69
73
66
56
33
37
pF
NOTE 4: Three-terminal guarded measurement, unmeasured terminal voltage bias is zero. First six capacitance values, with bias VD, are
for the R-G and T-G terminals only. The last capacitance value, with bias VDTR, is for the T-R terminals.
Thermal Characteristics
TISP70xxF3 (LV) Overvoltage Protector Series
Parameter Test Conditions Min Typ Max Unit
Rθ
JA Junction to free air thermal resistance Ptot =0.8W, T
A= 25 C
5cm
2, FR4 PCB 160 C/W
°°
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Parameter Measurement Information
TISP70xxF3 (LV) Overvoltage Protector Series
Figure 1. Voltage-Current Characteristic for T and R Terminals
T and G and R and G Measurements are Referenced to the G Terminal
T and R Measurements are Referenced to the R Terminal
-v V
DRM
I
DRM
V
D
I
H
I
TSM
I
TSP
V
(BO)
I
(BO)
I
D
Quadrant I
Switching
Characteristic
+v
+i
V
(BO)
I
(BO)
V
DRM
I
DRM
V
D
I
D
I
H
I
TSM
I
TSP
-i
Quadrant III
Switching
Characteristic PMXXAAA
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Typical Characteristics - R and G, or T and G Terminals
TISP70xxF3 (LV) Overvoltage Protector Series
Figure 2. Figure 3.
Figure 4. Figure 5.
T
J
- Junction Temperature - °C
-25 0 25 50 75 100 125 150
I
D
- Off-State Current A - µ
1
0-1
0-01
0-001
10
100 TC7LAC
V
D
= -50 V
V
D
= 50 V
T
J
- Junction Temperature -
-25 0 25 50 75 100 125 150
Normalized Breakdown Voltages
0.9
1.0
1.1
1.2
TC7LAE
V
(BO)
V
(BR)
V
(BR)M
Positive Polarity
Normalized to V
(BR)
I
(BR)
= 1 mA a Cnd 25 °
T
J
- Junction Temperature -
-25 0 25 50 75 100 125 150
Normalized Breakdown Voltages
0.9
1.0
1.1
1.2
TC7LAF
V
(BO)
V
(BR)
V
(BR)M
Negative Polarity
Normalized to V
(BR)
I
(BR)
= 1 mA and 25
V
T
- On-State Voltage - V
2345678911 0
I
T
- On-State Current - A
1
10
100 TC7LAL
-40
150 25
Positive Polarity
OFF-STATE CURRENT
vs
JUNCTION TEMPERATURE
OFF-STATE CURRENT
vs
ON-STATE VOLTAGE
NORMALIZED BREAKDOWN VOLTAGES
vs
JUNCTION TEMPERATURE
NORMALIZED BREAKDOWN VOLTAGES
vs
JUNCTION TEMPERATURE
°C
°C
°C
°C°C
°C
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
TISP70xxF3 (LV) Overvoltage Protector Series
Typical Characteristics - R and G, or T and G Terminals
Figure 6. Figure 7.
Figure 8. Figure 9.
V
T
- On-State Voltage - V
23456789110
I
T
- On-State Current - A
1
10
100
TC7LAM
-40
150 25
Negative Polarity
T
J
- Junction Temperature -
-25 0 25 50 75 100 125 150
I
H
, I
(BO)
- Holding Current, Breakover Current - A
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.1
1.0
TC7LAH
I
H
+I
(BO)
-I
(BO)
di/dt - Rate of Rise of Principle Current - A/µs
10-001 0-01 0-1 10 100
Normalized Breakover Voltage
1.0
1.1
1.2
1.3
1.4
1.5
TC7LAU
Positive
Negative
10 100 1000
Maximum Surge Current - A
10
100
1000
TC7LAA
2
ON-STATE CURRENT
vs
ON-STATE VOLTAGE
SURGE CURRENT
vs
DECAY TIME
HOLDING CURRENT & BREAKOVER CURRENT
vs
JUNCTION TEMPERATURE
NORMALIZED BREAKOVER VOLTAGE
vs
RATE OF RISE PRINCIPLE CURRENT
°C°C
°C
°C
Decay Time - µs
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Typical Characteristics - R and T Terminals
TISP70xxF3 (LV) Overvoltage Protector Series
Figure 10. Figure 11.
Figure 12. Figure 13.
T
J - Junction Temperature - °C
-25 0 25 50 75 100 125 150
ID - Off-State Current - µA
1
0-1
0-01
0-001
10
100
TC7LAD
TJ - Junction Temperature -
-25 0 25 50 75 100 125 150
Normalized Breakdown Voltages
0.9
1.0
1.1
1.2
TC7LAG
V(BO)
V(BR)
V(BR)M
VT - On-State Voltage - V
23456789110
IT - On-State Current - A
1
10
100
TC7LAK
-40
150 25
TJ - Junction Temperature -
-25 0 25 50 75 100 125 150
IH, I(BO) - Holding Current, Breakover Current - A
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.1
1.0
TC7LAJ
IH
I(BO)
OFF-STATE CURRENT
vs
JUNCTION TEMPERATURE
HOLDING CURRENT & BREAKOVER CURRENT
vs
JUNCTION TEMPERATURE
NORMALIZED BREAKDOWN VOLTAGES
vs
JUNCTION TEMPERATURE
ON-STATE CURRENT
vs
ON-STATE VOLTAGE
°C
°C°C
°C
°C
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Thermal Information
TISP70xxF3 (LV) Overvoltage Protector Series
Figure 14. Figure 15.
t - Current Duration - s
10-1 10 100 1000
ITRMS - Maximum Non-Recurrent 50 Hz Current - A
1
10
TI7LAA
VGEN = 250 Vrms
RGEN = 10 to 150 Ω
t - Power Pulse Duration - s
10.0001 0.001 0.01 0.1 10 100 1000
ZθJA - Transient Thermal Impedance - °C/W
1
10
100
TI7MAB
MAXIMUM NON-RECURRING 50 Hz CURRENT
vs.
CURRENT DURATION THERMAL RESPONSE
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Thermal Information
TISP70xxF3 (LV) Overvoltage Protector Series
Non-Repetitive Peak On-state Pulse Derated Values for 0 °C ≤ TA ≤ 70 °C
Rating Symbol Value Unit
Non-repetitive peak on-state pulse current, 0 °C < TA < 70 °C (see Notes 5, 6 and 7)
IPPSM A
1/2 (Gas tube differential transient, 1/2 voltage wave shape) 130
2/10 (Telcordia GR-1089-CORE, 2/10 voltage wave shape) 80
1/20 (ITU-T K.22, 1.2/50 voltage wave shape, 25 Ω resistor) 45
8/20 (IEC 61000-4-5, combination wave generator, 1.2/50 voltage wave shape) 75
10/160 (FCC Part 68, 10/160 voltage wave shape) 55
4/250 (ITU-T K.20/21, 10/700 voltage wave shape, dual) 50
0.2/310 (CNET I 31-24, 0.5/700 voltage wave shape) 50
5/310 (ITU-T K.20/21, 10/700 voltage wave shape, single) 50
5/320 (FCC Part 68, 9/720 voltage wave shape) 50
10/560 (FCC Part 68, 10/560 voltage wave shape) 40
10/1000 (Telcordia GR-1089-CORE, 10/1000 voltage wave shape) 40
NOTES: 5. Initially, the TISP device must be in thermal equilibrium at the specified T . The impulse may be repeated after the TISP device
returns to its initial conditions. The rated current values may be applied either to the R to G or to the T to G or to the T to R
terminals. Additionally, both R to G and T to G may have their rated current values applied simultaneously (In this case the total
G terminal current will be twice the above rated current values).
A®®
6. See Applications Information for details on wave shapes.
7. Above 70 °C, derate IPPSM linearly to zero at 150 °C lead temperature.
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Deployment
Wave Shape Notation
Generators
ITU-T 10/700 Generator
APPLICATIONS INFORMATION
TISP70xxF3 (LV) Overvoltage Protector Series
These devices are three terminal overvoltage protectors. They limit the voltage between three points in the circuit. Typically, this would be the
two line conductors and protective ground (Figure 16).
In Figure 16, protective functions Th2 and Th3 limit the maximum voltage between each conductor and ground to their respective ±V(BO)
values. Protective function Th1 limits the maximum voltage between the two conductors to its ±V(BO) value.
Lightning Surge
Most lightning tests, used for equipment verification, specify a unidirectional sawtooth waveform which has an exponential rise and an
exponential decay. Wave shapes are classified in terms of rise time in microseconds and a decay time in microseconds to 50 % of the maximum
amplitude. The notation used for the wave shape is
rise time/decay time,
without the microseconds quantity and the “/” between the two values
has no mathematical significance. A 50 A, 5/310 waveform would have a peak current value of 50 A, a rise time of 5 µs and a decay time of 310
µs. The TISP® surge current graph comprehends the wave shapes of commonly used surges.
There are three categories of surge generator type: single wave shape, combination wave shape and circuit defined. Single wave shape
generators have essentially the same wave shape for the open circuit voltage and short circuit current (e.g., 10/1000 open circuit voltage and
short circuit current). Combination generators have two wave shapes, one for the open circuit voltage and the other for the short circuit current
(e.g., 1.2/50 open circuit voltage and 8/20 short circuit current). Circuit specified generators usually equate to a combination generator,
although typically only the open circuit voltage wave shape is referenced (e.g., a 10/700 open circuit voltage generator typically produces a 5/
310 short circuit current). If the combination or circuit defined generators operate into a finite resistance, the wave shape produced is
intermediate between the open circuit and short circuit values.
This circuit defined generator is specified in many standards. The descriptions and values are not consistent between standards and it is
important to realize that it is always the same generator being used.
Figure 17 shows the 10/700 generator circuit defined in ITU-T recommendation K.20 (10/96) “Resistibility of telecommunication switching
equipment to overvoltages and overcurrents”. The basic generator comprises of:
Capacitor C1, charged to voltage VC, which is the energy storage element.
Switch SW to discharge the capacitor into the output shaping network.
Shunt resistor R1, series resistor R2 and shunt capacitor C2 form the output shaping network.
Series feed resistor R3 to connect to one line conductor for single surge.
Series feed resistor R4 to connect to the other line conductor for dual surging.
In the normal single surge equipment test configuration, the unsurged line is grounded. This is shown by the dotted lines in the top drawing of
Figure 17. However, doing this at device test places one terminal pair in parallel with another terminal pair. To check the individual terminal pairs
of the TISP7xxxF3, without any paralleled operation, the unsurged terminal is left unconnected.
With the generator output open circuit, when SW closes, C1 discharges through R1. The decay time constant will be C1 R1, or
20 x 50 = 1000 µs. For the 50 % voltage decay time, the time constant needs to be multiplied by 0.697, giving 0.697 x 1000 = 697 µs which is
rounded to 700 µs.
Figure 16. MULTI-POINT PROTECTION
Th3
Th2
Th1
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
APPLICATIONS INFORMATION
TISP70xxF3 (LV) Overvoltage Protector Series
ITU-T 10/700 Generator (continued)
Lightning Surge (continued)
The output rise time is controlled by the time constant of R2 and C2, which is 15 x 200 = 3000 ns or 3 µs. Virtual voltage rise times are given
by straight line extrapolation through the 30 % and 90 % points of the voltage waveform to zero and 100 %. Mathematically, this is equivalent to
3.24 times the time constant, which gives 3.24 x 3 = 9.73 which is rounded to 10 µs. Thus, the open circuit voltage rises in 10 µs and decays in
700 µs, giving the 10/700 generator its name.
When the overvoltage protector switches, it effectively shorts the generator output via the series 25 Ω resistor. Two short circuit conditions
need to be considered: single output using R3 only (top circuit of Figure 18) and dual output using R3 and R4 (bottom circuit of Figure 18).
For the single test, the series combination of R2 and R3 (15 + 25 = 40 Ω) is in shunt with R1. This lowers the discharge resistance from 50 Ω to
22.2 Ω, giving a discharge time constant of 444 µs and a 50% current decay time of 309.7 µs, which is rounded to 310 µs.
For the rise time, R2 and R3 are in parallel, reducing the effective source resistance from 15 Ω to 9.38 Ω, giving a time constant of 1.88 µs.
Virtual current rise times are given by straight line extrapolation through the 10 % and 90 % points of the current waveform to zero and 100 %.
Mathematically, this is equivalent to 2.75 times the time constant, which gives 2.75 x 1.88 = 5.15, which is rounded to 5 µs. Thus, the short
circuit current rises in 5 µs and decays in 310 µs, giving the 5/ 310 wave shape.
The series resistance from C1 to the output is 40 Ω giving an output conductance of 25 A/kV. For each 1 kV of capacitor charge voltage, 25 A
of output current will result.
For the dual test, the series combination of R2 plus R3 and R4 in parallel (15 + 12.5 = 27.5 Ω) is in shunt with R1. This lowers the discharge
resistance from 50 Ω to 17.7 Ω, giving a discharge time constant of 355 µs and a 50 % current decay time of 247 µs, which is rounded to
250 µs.
For the rise time, R2, R3 and R4 are in parallel, reducing the effective source resistance from 15 Ω to 6.82 Ω, giving a time constant of 1.36 µs,
which gives a current rise time of 2.75 x 1.36 = 3.75, which is rounded to 4 µs. Thus, the short circuit current rises in 4 µs and decays in 250
µs, giving the 4/250 wave shape.
Figure 17.
C2
200 nF
R1
50 Ω
ΩΩ
Ω
Ω
ΩΩ
C1
20 µF
R2
15
SW
VC
2.8 kV R3
25
RT
T
G
TR
G
R
G
T AND G
TEST R AND G
TEST R AND T
TEST
70 A
5/310
70 A
5/310
10/700 GENERATOR - SINGLE TERMINAL PAIR TEST
C2
200 nF
R1
50
C1
20 µF
R2
15
SW R3
25
R4
25
RT
G
DUAL
T AND G,
R AND G
TEST
95 A
4/250
95 A
4/250
190 A
4/250
VC
5.2 kV
10/700 GENERATOR - DUAL TERMINAL PAIR TEST
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
APPLICATIONS INFORMATION
TISP70xxF3 (LV) Overvoltage Protector Series
ITU-T 10/700 Generator (continued)
Lightning Surge (continued)
The series resistance from C1 to an
individual
output is 2 x 27.5 = 55 Ω, giving an output conductance of 18 A/kV. For each 1 kV of capacitor
charge voltage, 18 A of output current will result.
At 25 °C, these protectors are rated at 70 A for the single terminal pair condition and 95 A for the dual condition (R and G terminals and T and
G terminals). In terms of generator voltage, this gives a maximum generator setting of 70 x 40 = 2.8 kV for the single condition and 2 x 95 x
27.5 = 5.2 kV for the dual condition. The higher generator voltage setting for the dual condition is due to the current waveform decay being
shorter at 250 µs compared to the 310 µs value of the single condition.
Other ITU-T recommendations use the 10/700 generator: K.17 (11/88) “Tests on power-fed repeaters using solid-state devices in order to
check the arrangements for protection from external interference” and K.21(10/96) “Resistibility of subscriber’s terminal to overvoltages and
overcurrents“, K.30 (03/93) “Positive temperature coefficient (PTC) thermistors”.
Several IEC publications use the 10/700 generator; common ones are IEC 6100-4-5 (03/95) “Electromagnetic compatibility (EMC) - Part 4:
Testing and measurement techniques - Section 5: Surge immunity test” and IEC 60950 (04/99) “Safety of information technology equipment”.
The IEC 60950 10/700 generator is carried through into other “950” derivatives. Europe is harmonized by CENELEC (Comité Européen de
Normalization Electro-technique) under EN 60950 (included in the Low Voltage Directive, CE mark). US has UL (Underwriters Laboratories)
1950 and Canada CSA (Canadian Standards Authority) C22.2 No. 950.
FCC Part 68 “Connection of terminal equipment to the telephone network” (47 CFR 68) uses the 10/700 generator for Type B surge testing.
Part 68 defines the open circuit voltage wave shape as 9/720 and the short circuit current wave shape as 5/320 for a single output. The current
wave shape in the dual (longitudinal) test condition is not defined, but it can be assumed to be 4/250.
Several VDE publications use the 10/700 generator; for example: VDE 0878 Part 200 (12/92) “Electromagnetic compatibility of information
technology equipment and telecommunications equipment; Immunity of analogue subscriber equipment”.
1.2/50 Generators
The 1.2/50 open circuit voltage and 8/20 short circuit current combination generator is defined in IEC 61000-4-5 (03/95) “Electromagnetic
compatibility (EMC) - Part 4: Testing and measurement techniques - Section 5: Surge immunity test”. This generator has a fictive output
resistance of 2 Ω, meaning that dividing the open circuit output voltage by the short circuit output current gives a value of 2 Ω (500 A/kV).
The combination generator has three testing configurations; directly applied for testing between equipment a.c. supply connections, applied
via an external 10 Ω resistor for testing between the a.c. supply connections and ground, and applied via an external 40 Ω resistor for testing
all other lines. For unshielded unsymmetrical data or signalling lines, the combination generator is applied via a 40 Ω resistor either between
lines or line to ground. For unshielded symmetrical telecommunication lines, the combination generator is applied to all lines via a resistor of n
x 40 Ω, where n is the number of conductors and the maximum value of external feed resistance is 250 Ω. Thus, for four conductors, n = 4 and
the series resistance is 4 x 40 = 160 Ω. For ten conductors, the resistance cannot be 10 x 40 = 400 Ω and must be 250 Ω. The combination
generator is used for short distance lines, long distance lines are tested with the 10/700 generator.
When the combination generator is used with a 40 Ω or more, external resistor, the current wave shape is not 8/20, but becomes closer to the
open circuit voltage wave shape of 1.2/50. For example, a commercial generator when used with 40 Ω produced an 1.4/50 wave shape.
The wave shapes of 1.2/50 and 8/20 occur in other generators as well. British Telecommunication has a combination generator with 1.2/50
voltage and 8/20 current wave shapes, but it has a fictitious resistance of 1 Ω. ITU-T recommendation K.22 “Overvoltage resistibility of
equipment connected to an ISDN T/S BUS” (05/95) has a 1.2/50 generator option using only resistive and capacitive elements, Figure 19.
The K.22 generator produces a 1.4/53 open circuit voltage wave. Using 25 Ω output resistors gives a single short circuit current output wave
shape of 0.8/18 with 26 A/kV and a dual of 0.6/13 with 20 A/kV. These current wave shapes are often rounded to 1/20 and 0.8/14. There are 8/
20 short circuit current defined generators. These are usually very high current, 10 kA or more and are used for testing a.c. protectors, primary
protection modules and some Gas Discharge Tubes.
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
APPLICATIONS INFORMATION
TISP70xxF3 (LV) Overvoltage Protector Series
1.2/50 Generators (continued)
Lightning Surge (continued)
Impulse Testing
To verify the withstand capability and safety of the equipment, standards require that the equipment is tested with various impulse wave forms.
The table in this section shows some common test values.
Manufacturers are being increasingly required to design in protection coordination. This means that each protector is operated at its design
level and currents are diverted through the appropriate protector, e.g.,the primary level current through the primary protector and lower levels
of current may be diverted through the secondary or inherent equipment protection. Without coordination, primary level currents could pass
through the equipment only designed to pass secondary level currents. To ensure coordination happens with fixed voltage protectors, some
resistance is normally used between the primary and secondary protection (R1a and R1b, Figure 20). The values given in this data sheet apply
to a 400 V (d.c. sparkover) gas discharge tube primary protector and the appropriate test voltage when the equipment is tested with a primary
protector.
If the impulse generator current exceeds the protector’s current rating, then a series resistance can be used to reduce the current to the
protector’s rated value to prevent possible failure. The required value of series resistance for a given waveform is given by the following
calculations. First, the minimum total circuit impedance is found by dividing the impulse generator’s peak voltage by the protector’s rated
current. The impulse generator’s fictive impedance (generator’s peak voltage divided by peak short circuit current) is then subtracted from the
minimum total circuit impedance to give the required value of series resistance. In some cases, the equipment will require verification over a
temperature range. By using the derated waveform values from the thermal information section, the appropriate series resistor value can be
calculated for ambient temperatures in the range of 0 °C to 70 °C.
Figure 18.
C2
30 nF
R1
76 Ω
C1
1 µF
R2
13 Ω
SW
VC
1 kV
K.22 1.2/50 GENERATOR
C3
C4
8 nF
8 nF
NOTE: SOME STANDARDS
REPLACE OUTPUT
CAPACITORS WITH
25 Ω RESISTORS
Standard
Peak Voltage
Setting
V
Voltage
Waveform
µs
Peak Current
Va lue
A
Current
Waveform
µs
TISP7xxxF3
25 °C Rating
A
Series
Resistance
Ω
Coordination
Resistance
Ω(Min.)
GR-1089-CORE 2500 2/10 2 x 500 2/10 2 x 190 12 NA
1000 10/1000 2 x 100 10/1000 2 x 45
FCC Part 68
(March 1998)
1500 10/160 200 10/160 110 6
NA
800 10/560 100 10/560 50 8
1000
1500
1500
9/720 †
(SINGLE)
(DUAL)
25
37.5
2 x 27
5/320 †
5/320 †
4/250
70
70
2 x 95
0
I 31-24 1500 0.5/700 37.5 0.2/310 70 0 NA
ITU-T K.20/K.21
1000
1500
4000
4000
10/700
(SINGLE)
(SINGLE)
(DUAL)
25
37.5
100
2 x 72
5/310
5/310
5/310
4/250
70
70
70
2 x 95
0
0
17
0
NA
NA
6
6
† FCC Part 68 terminology for the waveforms produced by the ITU-T recommendation K.21 10/700 impulse generator
NA = Not Applicable, primary protection removed or not specified.
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
Off-State Capacitance
The protection voltage, (V(BO) ), increases under lightning surge conditions due to thyristor regeneration. This increase is dependent on the
rate of current rise, di/dt, when the TISP® device is clamping the voltage in its breakdown region. The V(BO) value under surge conditions can
be estimated by multiplying the 50 Hz rate V(BO) (250 V/ms) value by the normalized increase at the surge’s di/dt. An estimate of the di/dt can
be made from the surge generator voltage rate of rise, dv/dt, and the circuit resistance.
As an example, the ITU-T recommendation K.21 1.5 kV, 10/700 surge has an average dv/dt of 150 V/µs, but, as the rise is exponential, the
initial dv/dt is three times higher, being 450 V/µs. The instantaneous generator output resistance is 25 Ω. If the equipment has an additional
series resistance of 20 Ω, the total series resistance becomes 45 Ω. The maximum di/dt then can be estimated as 450/45 = 10 A/µs. In
practice, the measured di/dt and protection voltage increase will be lower due to inductive effects and the finite slope resistance of the TISP®
breakdown region.
Capacitance
The off-state capacitance of a TISP® device is sensitive to junction temperature, TJ, and the bias voltage, comprising of the dc voltage, VD,
and the ac voltage, Vd. All the capacitance values in this data sheet are measured with an ac voltage of 1 Vrms. When VD >> Vd, the capaci-
tance value is independent on the value of Vd. Up to 10 MHz, the capacitance is essentially independent of frequency. Above 10 MHz, the
effective capacitance is strongly dependent on connection inductance. For example, a printed wiring (PW) trace of 10 cm could create a circuit
resonance with the device capacitance in the region of 80 MHz.
Longitudinal Balance
Figure 19 shows a three terminal TISP® device with its equivalent “delta” capacitance. Each capacitance, CTG, CRG and CTR, is the true
terminal pair capacitance measured with a three terminal or guarded capacitance bridge. If wire R is biased at a larger potential than wire T,
then CTG >CRG. Capacitance CTG is equivalent to a capacitance of CRG in parallel with the capacitive difference of (CTG - CRG). The line
capacitive unbalance is due to (CTG - CRG) and the capacitance shunting the line is CTR +CRG /2.
All capacitance measurements in this data sheet are three terminal guarded to allow the designer to accurately assess capacitive unbalance
effects. Simple two terminal capacitance meters (unguarded third terminal) give false readings as the shunt capacitance via the third terminal is
included.
APPLICATIONS INFORMATION
TISP70xxF3 (LV) Overvoltage Protector Series
Protection Voltage
Figure 19.
MARCH 1994 - REVISED SEPTEMBER 2008
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
TISP70xxF3 (LV) Overvoltage Protector Series
Typical Circuits
APPLICATIONS INFORMATION
Figure 20. Protection Module
Figure 21. ISDN Protection
Figure 22. Line Card Ring/Test Protection
PROTECTED
EQUIPMENT
AI7XBP
TISP7xxxF3
Th3
Th2
Th1
R1a
R1b
RING
WIRE
TIP
WIRE F1a
F1b
GDTb
GDTa
R1a
R1b
AI7XBM
SIGNAL
D.C.
Th3
Th2
Th1
TISP7150F3
TEST
RELAY RING
RELAY SLIC
RELAY
TEST
EQUIP-
MENT RING
GENERATOR
S1a
S1b
R1a
R1b
RING
WIRE
TIP
WIRE
Th3
Th2
Th1
Th4
Th5
SLIC
SLIC
PROTECTION
RING/TEST
PROTECTION
OVER-
CURRENT
PROTECTION
S2a
S2b
S3a
S3b
VBAT
C1
220 nF
AI7XBN
TISP6xxxx,
1/2 TISP6NTP2
COORDI-
NAT ION
RESISTANCE
TISP7xxxF3
“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.
Mouser Electronics
Authorized Distributor
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