TBU-DT Datasheet, PDF (2/5 Pages) –

Load Side
Line Side
OVP
TBU-DT Series - TBU^® Hig^Oh^VP-Speed Protectors
Load Side
Line Side
Reference ApplicatioTnBU^™ Device
The TBU^® device can be used to protect against excessive
voltage surges in transformer coupled equipment, as shown in
the figure below. The TBU^® protector prevents any surges from
causing damage. An overvoltage protection device, such as an
MOV or GDT, may be used to provide additional overvoltage
protection if the surge voltage is likely to be above the maximum
rating of the TBU^® device.
Basic TBU Operation
The TBU^® device is a silicon-based, solid-state, resettable
device which is placed in series with a signal path. The TBU^®
device operates in approximately 1 µs - once line current
exceeds the TBU^® device’s trigger current I_trigger. When
operated, the TBU^® device will limit the current to less than the
I_trigger value within the t_block duration. If voltage above V_reset
is continuously sustained, the TBU^® device will subsequently
reduce the current to a quiescent current level within a period of
time that is dependent upon the applied voltage.
Line
Side
1
2
OVP
OVP
4
3
TBU^® Device
Load
After the surge, the TBU^® device resets when the voltage
across the TBU^® device falls to the V_reset level. The TBU^®
device will automatically reset on lines which have no DC bias
or have DC bias below V_reset (such as unpowered signal lines).
If the line has a normal DC bias above V_reset, the voltage
across the TBU^® device may not fall below V_reset after the
surge. In such cases, special care needs to be taken to ensure
that the TBU^® device will reset, otherwise an automatic or
manual power down will be required. Bourns application
engineers can provide further assistance.
Performance Graphs
V-I Characteristic - TBU-DT085-300-WH (Pin 2-1 & Pin 3-4)
ITRIP
CURRENT
(100 mA/div.)
VRESET
VOLTAGE
(5 v/div.)
Typical Trigger Current vs. Temperature
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-75 -50 -25 0 25 50 75 100 125 150
Junction Temperature (°C)
Specifications are subject to change without notice.
The device characteristics and parameters in this data sheet can and do vary in different applications and actual device performance may vary over time.
Users should verify actual device performance in their specific applications.