This Product Selection Guide contains information to help select products in the Thyristors - DIACs, SIDACs category on DigiKey.com
Products in the DIAC and SIDAC family are two-terminal devices most commonly used as triggering mechanisms in AC phase control applications. They act to oppose current flow until the voltage applied across them reaches some critical value, at which point current flow through them increases significantly. The two differ in the shape of their characteristic curves; DIACs (Diodes for Alternating Current) generally exhibit higher forward voltages in their conductive mode, and thus tend to be less suitable than SIDACs (Silicon Diode for Alternating Current) when substantial current flow is an application requirement.
SelectionCharacteristics
Specifications to determine which DIAC or SIDAC is right for your application.
Voltage - Breakover: Characterizes the applied voltage at which a device enters into a conductive state.
Current - Breakover: The maximum current flow through a device’s main terminals required for “triggering” or entry into a negative-resistance mode of operation.
Current - Hold (Ih) (Max): Characterizes the minimum current flow through a device required to maintain a conductive state.
Current - Peak Output: The maximum current flow a device is able tolerate on a repetitive, ongoing basis, such as at the peak of an applied 60 Hz AC waveform.
Operating Temperature: Recommended operating temperature, typically given in a range or as a maximum. Exceeding these temperatures may affect performance or damage the device and other system components.
Package / Case: Indicates the type of protective case used on an electronic component to allow easy handling, installation, and protection. This selection was determined to be the closest industry standard applicable to the supplier’s device packaging. Typically it is best to check the actual dimensions from the datasheet rather than depend on this terminology when designing your circuit.
Supplier Device Package: This is what the manufacturer calls the package of this device. They are manufacturer specific. It is typically best to use the actual dimensions from the datasheets rather than to go by this terminology when designing your circuit.
ProductExamples
| MFR PART # | SODDB3T RHG |
|---|---|
| DIGI-KEY PART # | SODDB3TRHGTR-ND - Tape & Reel (TR) |
| MANUFACTURER | Taiwan Semiconductor Corporation |
| DESCRIPTION | Diac/Sidac Thyristor 30 ~ 34V SOD-123 |
| DATASHEET | Click Here |
| MFR PART # | BS08D-T112 |
|---|---|
| DIGI-KEY PART # | 835-1126-1-ND - Cut Tape (CT) |
| MANUFACTURER | Powerex Inc. |
| DESCRIPTION | Diac/Sidac Thyristor 7 ~ 9V TO-92 |
| DATASHEET | Click Here |
| MFR PART # | TMMDB3 |
|---|---|
| DIGI-KEY PART # | 497-3275-2-ND - Tape & Reel (TR) |
| MANUFACTURER | STMicroelectronics |
| DESCRIPTION | Diac/Sidac Thyristor 28 ~ 36V Mini MELF |
| DATASHEET | Click Here |
| MFR PART # | K1200G |
|---|---|
| DIGI-KEY PART # | F6592-ND |
| MANUFACTURER | Littelfuse Inc. |
| DESCRIPTION | Diac/Sidac Thyristor 110 ~ 125V DO-15 |
| DATASHEET | Click Here |
Schematic Symbol
DIAC/SIDAC schematic symbol courtesy of Scheme-It please use the link for more information and symbols.
MediaLinks
Articles
Articles featuring DIACs
TechForum
TechForum posts on DIACs
TechForum posts on SIDACs