9EL2 Datasheet, PDF (1/5 Pages) Bourns Electronic Solutions – BIDIRECTIONAL THYRISTOR OVERVOLTAGE PROTECTORS

9EL2, 9EL3
BIDIRECTIONAL THYRISTOR OVERVOLTAGE PROTECTORS
9ELx Primary Protector Series
Ion-Implanted Breakdown Region
- Precise and Stable Voltage
- Low Voltage Overshoot under Surge
Device
9EL2
9EL3
V_(BR)
V_(BO)
V_(BO)
Minimum Minimum Maximum
V
±245
V
±265
±200
V
±400
±265
Rated for International Surge Wave Shapes
Device
9EL2
9EL3
ITU-T K28
(10/700)
I_TSP
A
±200
±125
GR-974-CORE
(10/1000)
I_TSP
A
±150
±100
Cell Package (Side View)
T( A)
R( B)
Device Symbol
T
MD4XACAa
Gas Discharge Tube (GDT) Replacement
Planar Passivated Junctions in a Protected Cell Construction
- Low Off-State Current
-Extended Service Life
Soldered Copper Electrodes
- High Current Capability
- Cell Construction Short Circuits Under Excessive Current Conditions
............................................ UL Recognized Components
R
SD4XAA
Terminals T and R correspond to the
alternative line designators of A and B
Description
These devices are primary protector components for semiconductor arrester assemblies intended to meet the generic requirements of
Telcordia GR-974-CORE or ITU-T Recommendation K28 (03/93). To conform to the specified environmental requirements, the 9ELx must be
installed in a housing which maintains a stable microclimate during these tests (e.g. FIGURE I.1/K28).
The protector consists of a symmetrical voltage-triggered bidirectional thyristor. 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. In usual applications, the high crowbar holding current prevents
d.c. latchup as the diverted current subsides. This 9ELx range consists of two voltage variants to meet various maximum system voltage
levels. They are designed to voltage limit and withstand the listed international lightning surges in both polarities.
These monolithic protection devices are constructed using two nickel plated copper electrodes soldered to each side of the silicon chip. This
packaging approach allows heat to be removed from both sides of the silicon, resulting in the doubling of the devices thermal capacity,
enabling a power line cross current capability of 10 A rms for 1 second. One of the 9ELx’s copper electrodes is specially shaped to promote a
progressive shorting action (at 50/60 Hz currents greater than 60 A). The assembly must hold the 9ELx in compression, so that the cell
electrodes can be forced together during overstress testing. Under excessive power line cross conditions the 9ELx will fail short circuit,
providing maximum protection to the equipment.
JANUARY 1994 - REVISED OCTOBER 2003
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.
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