Internally Triggered Triacs (4 A to 15 A) RoHS
Teccor’s Quadrac devices are triacs that include a diac trigger
mounted inside the same package. This device, developed by
Teccor, saves the user the expense and assembly time of buying
a discrete diac and assembling in conjunction with a gated triac.
Also, the alternistor Quadrac device (QxxxxLTH) eliminates the
need for a snubber network.
The Quadrac device is a bidirectional AC switch and is gate con-
trolled for either polarity of main terminal voltage. Its primary pur-
pose is for AC switching and phase control applications such as
speed controls, temperature modulation controls, and lighting
controls where noise immunity is required.
Triac current capacities range from 4 A to 15 A with voltage
ranges from 200 V to 600 V. Quadrac devices are available in the
The TO-220 package is electrically isolated to 2500 V rms from
the leads to mounting surface. 4000 V rms is available on special
order. This means that no external isolation is required, thus
eliminating the need for separate insulators and insulator-mount-
ing steps and saving dollars over “hot tab” devices.
All Teccor triac and diac chips have glass-passivated junctions to
ensure long-term device reliability and parameter stability.
Variations of devices in this data sheet are available for custom
design applications. Consult the factory for more information.
• RoHS Compliant
• Glass-passivated junctions
• Electrically-isolated package
• Internal trigger diac
• High surge capability — up to 200 A
• High voltage capability — 200 V to 600 V
©2004 Littelfuse, Inc.
Thyristor Product Catalog
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