The DB3/DB4 series is a trigger diode with a fixed voltage reference, which can be used in conjunction with triacs for simplified gate control circuits or as a starting element in fluorenscent lamp ballasts.
This document provides technical specifications for the STMicroelectronics DB3, DB4, and SMDB3 DIAC series. It describes their function as trigger diodes for use with triacs and in fluorescent lamp ballasts, highlighting features such as low breakover current and availability in DO-35 and SOT-23 packages.
The datasheet details absolute maximum ratings, including a repetitive peak on-state current of 1.00A for the SMDB3 and 2.00A for the DB3/DB4 series. It also lists electrical characteristics such as breakover voltage ranges (28-36V for DB3, 35-45V for DB4) and provides mechanical dimensions for both DO-35 and SOT-23 packages.
| Repetitive peak on-state current (SMDB3) | 1.00 A |
|---|---|
| Repetitive peak on-state current (DB3/DB4) | 2.00 A |
| Storage temperature range | - 40 to + 125 °C |
| Breakover voltage (SMDB3) | 28 - 36 V |
| Breakover voltage (DB3) | 28 - 36 V |
| Breakover voltage (DB4) | 35 - 45 V |
The SMDB3 is available in the SOT-23 package.
These devices function as trigger diodes with a fixed voltage reference that can be used with triacs for simplified gate control circuits or as starting elements in fluorescent lamp ballasts.
The storage temperature range is from -40 to +125 °C.
The maximum repetitive peak on-state current for the DB3 and DB4 models is 2.00 A.