Bidirectional TVS Diodes and Mixed Polarity Options
Explore bidirectional transient-voltage-suppression (TVS) and compact ESD protection listings alongside selectable TVS grades. This collection currently includes SMBJ surface-mount choices, an axial 1.5KE menu, and two fixed compact ESD devices. Not every item or option is bidirectional: the SMBJ and 1.5KE menus include both CA and A suffixes, and a BC857CW-TP listing has a conflicting TVS headline. Match the actual selected model to a manufacturer datasheet before designing it into a circuit.
What the listings offer
- SMBJ SMD TVS: separate 20-piece and 50-piece listings let you select one grade per order. CA choices include SMBJ5.0CA, SMBJ6.0CA, SMBJ6.5CA and SMBJ12CA; the same menus also list A choices such as SMBJ5.0A, SMBJ7.0A, SMBJ12A, SMBJ15A, SMBJ40A and SMBJ48A. Some 20-piece options repeat a model with extra spaces; check the exact selection rather than treating the title as a mixed assortment.
- Axial 1.5KE: the 10-piece through-hole listing offers one selected 1.5KE A or CA grade, with option numbers spanning 6.8 to 36. CA and A are different choices, not ten of every grade named in the title.
- Compact ESD listings: ESDSLC5V0LB-TP is listed in DFN1006 as a 100-piece pack; ESD5V0D3B-TP is listed in SOD-323 as another 100-piece pack. Check their device-specific polarity, pinout, working voltage, capacitance and test conditions. Compact ESD parts are not interchangeable with SMBJ or axial surge suppressors just because the descriptions mention a clamp voltage.
- Conflicting listing: BC857CW-TP appears as a 100-piece SOT-323 product whose title calls it a bidirectional TVS, while its model designation and source product type do not establish that function. Treat its TVS, 24 V, 44 V clamp and 7 A claims as unverified; verify the actual component identity before choosing it for protection.
Choose by electrical limits, not the headline
- Identify the protected line's normal positive and negative voltage excursions. In common TVS-family naming, CA indicates bidirectional and A unidirectional, but confirm the selected part number and manufacturer marking. Bidirectional behavior can suit lines that swing either way; direction alone does not establish suitability.
- Compare reverse standoff voltage (VRWM), breakdown voltage (VBR), clamping voltage (VC) at its stated pulse current, and the load's maximum tolerable transient. A 5.0 or 12 in a model name is not necessarily its clamping voltage.
- Review pulse waveform, peak current and power, repetition, temperature derating, leakage and capacitance from the exact device datasheet. Seller claims such as 80 W, 200 W or a clamp value cannot be generalized across all options or test waveforms.
- Match the board layout and mounting method: DFN1006, SOD-323, SMBJ and axial through-hole packages require different footprints and thermal treatment. Check selected pack size and model before ordering.
Frequently asked questions
Are all SMBJ choices on this page bidirectional?
No. Both SMBJ CA and A options appear. Select the exact suffix and verify its polarity in the device datasheet.
Does the 1.5KE listing contain every voltage shown?
No. Its option selects one 10-piece grade; A and CA versions are separate selections.
Can a compact ESD part replace an SMBJ TVS?
Not on package name or clamp voltage alone. Compare the complete electrical limits and pulse test conditions, plus footprint and pinout.
Is BC857CW-TP verified here as a bidirectional TVS?
No. Its listing information conflicts. Confirm the component's identity and specifications independently before using it as a protection device.
