Gate-drive isolation with 200 kV/µs CMTI margin
The Skyworks SI8273AB-IM1 is a dual-channel digital isolator from the Si827x family, purpose-built for driving power semiconductors across an isolation barrier. Its RF-coupling technology delivers 2500Vrms of galvanic isolation (cite:) while maintaining a common-mode transient immunity of 200 kV/µs minimum (cite:) — a figure that keeps the gate signal clean when the switching node slews at tens of kV/µs in a hard-switched half-bridge. The 4A peak output current (cite:) directly charges the gate capacitance of medium-power SiC and GaN FETs; the asymmetric source/sink capability — 1.8 A source, 4 A sink (cite:) — is optimised for fast turn-off where the Miller plateau demands a lower-impedance pull-down path.
Timing and temperature envelope
Propagation delay is matched at 75 ns max for both rising and falling edges (cite:), with pulse-width distortion held to 8 ns maximum (cite:). That matched delay matters in a dead-time window — the controller side must compensate for the same delay on both channels or the overlap calculation drifts with temperature. Rise and fall times are 10.5 ns and 13.3 ns typical respectively (cite:), so the gate driver transitions through the FET threshold region in a few nanoseconds — fast enough to minimise switching loss but not so fast that PCB layout parasitics dominate the ringing. Output supply voltage accepts 4.2 V to 30 V (cite:), which covers the gate drive rails for standard Si MOSFETs (10-15 V), SiC FETs (18-20 V), and GaN devices (5-6 V) from a single part — one BOM line serves multiple voltage domains.
The 14-VDFN package (cite:) with a 5x5 mm body (supplier device package 14-QFN, cite:) is a common footprint for isolated gate drivers. Approvals from CQC, CSA, UR, and VDE (cite:) cover the major North American, European, and Chinese regulatory schemes — the same qualification package supports a global BOM without region-specific variants.
Skyworks lists the SI8273AB-IM1 as Active with no NRND or EOL notification (cite:). ROHS3 compliant (cite:).
Comparison to SI8273ABD-IM1
The SI8273ABD-IM1 (cite:) is the same die in the same 14-QFN package — identical 2500Vrms isolation, 4 A peak output, 200 kV/µs CMTI, and 75 ns propagation delay. The 'D' suffix variant carries the same parametric profile; the two order codes are functionally interchangeable for a BOM line, though the exact date-code and lot traceability differ between the two Skyworks part numbers.