Standard TRIACs need an RC snubber across their main terminals when switching inductive loads (motors, transformers, solenoids). Without it, the rapid dv/dt at commutation — when load current lags voltage and the TRIAC tries to turn off while voltage is still climbing — can retrigger the device, causing it to stay conducting through the next half-cycle. The result: uncontrolled full-power operation and eventual failure.

Snubberless TRIACs (ST's "Snubberless" family, Littelfuse "Alternistor", NXP "Hi-Com") solve this by using two anti-parallel thyristor structures on the same die instead of a single bidirectional structure. Each half only conducts one polarity, so the "just turned off" side isn't sitting next to a still-conducting side sharing carriers. Commutating dv/dt ratings jump from ~10 V/µs (standard) to 500–1000 V/µs, and commutating di/dt from ~3 A/ms to 20+ A/ms.

Practical example: Phase-controlling a 230 VAC / 200 W universal motor (drill speed controller). A standard BTA16-600B needs an RC snubber (typically 100 Ω + 100 nF X2-rated across MT1–MT2) plus a matching gate snubber. The snubber dissipates 1–2 W continuously and the X2 cap is a bulky, expensive part. Swap in a BTA16-600CW (snubberless variant): delete both snubbers entirely. Board area drops, BOM shrinks, and reliability improves because you've removed the failure-prone X2 capacitor.

Gate drive still matters. Snubberless devices have higher gate trigger current (IGT typically 35 mA vs 10 mA for sensitive-gate parts) because the two half-structures are less tightly coupled. Design your MOC3021-style optotriac driver for the worst-case IGT at the coldest operating temperature — TRIACs get harder to trigger cold. A quick check:

• Gate resistor rule: R_gate = (V_peak − 3 V) / (1.2 × IGT_max). For 230 VAC and IGT = 50 mA: R = (325 − 3) / 0.060 ≈ 5.4 kΩ. Use 4.7 kΩ, 1 W (peak dissipation is brief but real).
• Still add: a small (33 Ω) gate series resistor plus 100 nF gate-to-MT1 for noise immunity — this is not a snubber, it just filters gate transients.

When you still need a snubber: highly inductive loads with power factor below 0.5 (large transformers, contactors driving big coils), or when line transients exceed the device's non-repetitive dv/dt spec. In those cases, add an MOV across the line and consider a smaller snubber (47 nF + 47 Ω) — a hybrid approach that keeps the benefits.

Watch the derating: snubberless parts trade some surge current (ITSM) for their commutation ruggedness. A 16 A snubberless TRIAC may have ITSM around 150 A vs 170 A for the standard version — matters for inrush-heavy loads like incandescent lamps or capacitor-input SMPS.