TISP4080M3LM Bourns Inc., TISP4080M3LM Datasheet - Page 10

• Manufacturer Part Number: TISP4080M3LM
• Description: SURGE SUPP THYRISTOR 65V TO-92
• Manufacturer: Bourns Inc.

Specifications of TISP4080M3LM

• Package / Case: TO-92-2, TO-226AC
• Voltage - Breakover: 80V
• Voltage - Off State: 65V
• Voltage - On State: 3V
• Current - Peak Pulse (8 X 20µs): 220A
• Current - Peak Pulse (10 X 1000µs): 50A
• Current - Hold (ih): 150mA
• Number Of Elements: 1
• Capacitance: 120pF
• Mounting Style: Through Hole
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

These devices are two terminal overvoltage protectors. They may be used either singly to limit the voltage between two conductors
(Figure 12) or in multiples to limit the voltage at several points in a circuit (Figure 13).
In Figure 12, protector Th1 limits the maximum voltage between the two conductors to ±V
protect circuits without a ground reference, such as modems. In Figure 13, protectors Th2 and Th3 limit the maximum voltage between each
conductor and ground to the ±V
±V
protector Th1 is not required.
To verify the withstand capability and safety of the equipment, standards require that the equipment is tested with various impulse wave
forms. The table below shows some common values
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 fi ctive 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.
For the FCC Part 68 10/560 waveform the following values result. The minimum total circuit impedance is 800/75 = 10.7 Ω and the gener-
ator’s fi ctive impedance is 800/100 = 8 Ω. This gives a minimum series resistance value of 10.7 - 8 = 2.7 Ω. After allowing for tolerance, a 3
Ω ±10% resistor would be suitable. The 10/160 waveform needs a standard resistor value of 5.6 Ω per conductor. These would be R1a and
R1b in Figure 15 and Figure 16. FCC Part 68 allows the equipment to be non-operational after the 10/160 (conductor to ground) and 10/560
(inter-conductor) impulses. The series resistor value may be reduced to zero to pass FCC Part 68 in a non-operational mode, e.g. Figure 14.
For this type of design, the series fuse must open before the TISP4xxxM3 fails. For Figure 14, the maximum fuse i
the equipment will require verifi cation over a temperature range. By using the rated waveform values from Figure 11, the appropriate series
resistor value can be calculated for ambient temperatures in the range of -40 °C to 85 °C.
Deployment
Impulse Testing
(BO)
TISP4xxxM3LM Overvoltage Protector Series
value. If the equipment being protected has all its vulnerable components connected between the conductors and ground, then
ITU-T K.20/K.21
GR-1089-CORE
(March 1998)
FCC Part 68 terminology for the waveforms produced by the ITU-T recommendation K.21 10/700 impulse generator
FCC Part 68
Standard
I3124
Figure 12. Two Point Protection
Peak Voltage
(BO)
Setting
2500
1000
1500
1500
1000
1500
1500
4000
800
V
of the individual protector. Protector Th1 limits the maximum voltage between the two conductors to its
Th1
Waveform
10/1000
Voltage
9/720
9/720
0.5/700
10/160
10/560
10/700
2/10
.
APPLICATIONS INFORMATION
Peak Current
Value
37.5
37.5
37.5
500
100
200
100
100
25
A
Customers should verify actual device performance in their specifi c applications.
Figure 13. Multi-point Protection
Waveform
10/1000
Current
5/320
5/320
0.2/310
10/160
10/560
5/310
2/10
(BO)
Th1
. This confi guration is normally used to
TISP4xxxM3
25 C Rating
Specifi cations are subject to change without notice.
Th3
Th2
300
120
100
100
100
100
75
50
A
NOVEMBER 1997 - REVISED JANUARY 2010
2
t is 2.3 A
Resistance
Series
2x5.6
11
2
3
0
0
0
0
s. In some cases,