TISP4350M3LM Bourns Inc., TISP4350M3LM Datasheet - Page 11
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TISP4350M3LM
Manufacturer Part Number
TISP4350M3LM
Description
SURGE SUPP THYRISTOR 275V TO-92
Manufacturer
Bourns Inc.
Specifications of TISP4350M3LM
Package / Case
TO-92-2, TO-226AC
Voltage - Breakover
350V
Voltage - Off State
275V
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
55pF
Mounting Style
Through Hole
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
TISP4350M3LM
Manufacturer:
BOURNS
Quantity:
240 000
Company:
Part Number:
TISP4350M3LM
Manufacturer:
PWRI
Quantity:
5 771
Part Number:
TISP4350M3LM
Manufacturer:
BOURNS/伯恩斯
Quantity:
20 000
The protector can withstand currents applied for times not exceeding those shown in Figure 8. Currents that exceed these times must be
terminated or reduced to avoid protector failure. Fuses, PTC (Positive Temperature Coeffi cient) resistors and fusible resistors are overcurrent
protection devices which can be used to reduce the current fl ow. Protective fuses may range from a few hundred milliamperes to one a
mpere. In some cases, it may be necessary to add some extra series resistance to prevent the fuse from opening during impulse testing. The
current versus time characteristic of the overcurrent protector must be below the line shown in Figure 8. In some cases there may be a further
time limit imposed by the test standard (e.g. UL 1459 wiring simulator failure).
The protector characteristic off-state capacitance values are given for d.c. bias voltage, V
values are also given for -100 V. Values for other voltages may be calculated by multiplying the V
in Figure 6. Up to 10 MHz, the capacitance is essentially independent of frequency. Above 10 MHz, the effective capacitance is strongly
dependent on connection inductance. In many applications, such as Figure 15 and Figure 17, the typical conductor bias voltages will be
about -2 V and -50 V. Figure 7 shows the differential (line unbalance) capacitance caused by biasing one protector at -2 V and the other at
-50 V.
The protector should not clip or limit the voltages that occur in normal system operation. For unusual conditions, such as ringing without the
line connected, some degree of clipping is permissible. Under this condition, about 10 V of clipping is normally possible without activating
the ring trip circuit.
Figure 10 allows the calculation of the protector V
maximum normal system voltages. The TISP4260M3LM, with a V
100 V rms of ring on a battery voltage of -58 V (Th2 and Th3 in Figure 17). The peak ring voltage will be 58 + 1.414*100 = 199.4 V. However,
this is the open circuit voltage and the connection of the line and its equipment will reduce the peak voltage. In the extreme case of an
unconnected line, clipping the peak voltage to 190 V should not activate the ring trip. This level of clipping would occur at the temperature
when the V
-28 °C. In this example, the TISP4260M3LM will allow normal equipment operation provided that the minimum expected ambient tempera-
ture does not fall below -28 °C.
To standardize thermal measurements, the EIA (Electronic Industries Alliance) has created the JESD51 standard. Part 2 of the standard
(JESD51-2, 1995) describes the test environment. This is a 0.0283 m
horizontally mounted at the center. Part 3 of the standard (JESD51-3, 1996) defi nes two test PCBs for surface mount components; one for
packages smaller than 27 mm (1.06 ’’) on a side and the other for packages up to 48 mm (1.89 ’’). The LM package measurements used the
smaller 76.2 mm x 114.3 mm (3.0 ’’ x 4.5 ’’) PCB. The JESD51-3 PCBs are designed to have low effective thermal conductivity (high thermal
resistance) and represent a worse case condition. The PCBs used in the majority of applications will achieve lower values of thermal resis-
tance and so can dissipate higher power levels than indicated by the JESD51 values.
NOVEMBER 1997 - REVISED JANUARY 2010
Specifi cations are subject to change without notice.
Customers should verify actual device performance in their specifi c applications.
AC Power Testing
Capacitance
Normal System Voltage Levels
JESD51 Thermal Measurement Method
TISP4xxxM3LM Overvoltage Protector Series
DRM
has reduced to 190/200 = 0.95 of its 25 °C value. Figure 10 shows that this condition will occur at an ambient temperature of
DRM
APPLICATIONS INFORMATION
value at temperatures below 25 °C. The calculated value should not be less than the
DRM
3
of 200 V, can be used for the protection of ring generators producing
(1 ft
3
) cube which contains the test PCB (Printed Circuit Board)
D
, values of 0, -1 V, -2 V and -50 V. Where possible,
D
= 0 capacitance value by the factor given