Skyworks Solutions Inc. SI8231AB-D-IS

Overview

SI8231AB-D-IS from Skyworks Solutions is a high-side/low-side isolated gate driver IC with PWM input, 0.5 A peak output current, 2.5 kVRMS isolation rating, and SOIC-16 narrow-body package. It integrates two independently isolated drivers using proprietary silicon isolation technology and supports half-bridge MOSFET/IGBT drive in power converters requiring overlap protection and programmable dead time.

For engineers reviewing the SI8231AB-D-IS datasheet, SI8231AB-D-IS pinout, SI8231AB-D-IS application, or SI8231AB-D-IS equivalent, this page delivers verified technical context, real-world design meaning of key specs, validated pin functions, confirmed automotive-grade qualification (AEC-Q100), and two rigorously cross-checked alternative parts for isolated gate drive selection.

Technical Context

The SI8231AB-D-IS implements RF-based on/off keying modulation across a semiconductor isolation barrier, delivering robust noise immunity and eliminating startup initialization requirements. Its single PWM input controls complementary high-side (VOA) and low-side (VOB) outputs with built-in overlap protection and user-programmable dead time via external resistor (R_DT).

Each channel features independent undervoltage lockout (UVLO) monitoring: VDDI UVLO threshold is 5 V (−100 mV hysteresis), while VDDA/VDDB UVLO thresholds are also 5 V. Outputs default low during UVLO or disable assertion, and propagation delay is ≤45 ns (typ) with 8 MHz max switching frequency support.

Key Specifications

Pinout & Package

SI8231AB-D-IS uses a RoHS-compliant SOIC-16 narrow-body package (10.3 × 7.5 mm, 1.27 mm pitch) with creepage/clearance optimized for 2.5 kVRMS working voltage.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar isolated gate driver applications.

Compared with SI8231AD-D-IS, the SI8231AB-D-IS trades isolation margin for smaller PCB area and lower cost in non-medical 2.5 kVRMS applications; versus UCC21520DWR, it offers simpler 5 V-only interface and proven AEC-Q100 qualification but lower drive strength for demanding GaN/SiC gates.

Availability

SI8231AB-D-IS is available at Aetrix Electronics and suitable for motor control systems, solar inverters, onboard chargers, and industrial UPS systems requiring stable component supply with automotive-grade reliability and 2.5 kVRMS isolation.

Supply support for SI8231AB-D-IS includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Skyworks Solutions is a global semiconductor company specializing in analog and mixed-signal connectivity solutions, with leadership in RF, isolation, and precision timing technologies.

The Si823x family was designed specifically for isolated gate driving in high-reliability power conversion systems, emphasizing robustness against CMTI, programmable timing control, and automotive qualification from the outset.

FAQ

What is the isolation voltage rating of the SI8231AB-D-IS and which safety standards does it meet?

The SI8231AB-D-IS has a 2.5 kVRMS input-to-output isolation rating per UL 1577. It meets CSA 62368-1 (reinforced insulation), VDE 60747-17 (basic insulation), and CQC GB4943.1 (reinforced insulation). This makes SI8231AB-D-IS suitable for industrial power supplies and inverters requiring basic or reinforced insulation at 2.5 kVRMS, but not for medical 2 MOPP or high-voltage grid-tie applications requiring ≥5 kVRMS.

How does the SI8231AB-D-IS implement dead time control and what is its minimum achievable value?

The SI8231AB-D-IS implements dead time control via an external resistor (R_DT) connected from pin 15 (DT) to ground, with DT ≈ 10 × R_DT ns. The minimum dead time is ~400 ps when DT is left floating or tied to VDDI. This allows precise tuning to match gate driver propagation mismatch in SiC/GaN half-bridges without firmware overhead - a key advantage over fixed-dead-time alternatives.

Does the SI8231AB-D-IS support bootstrap high-side configuration and what is the maximum recommended drain voltage?

Yes, the SI8231AB-D-IS supports bootstrap high-side configuration as confirmed in Figure 33 of the datasheet. VOA is rated for high-side operation with a maximum drain voltage of 1500 V when used with appropriate external bootstrap components (e.g., CB capacitor, D1 diode). This enables direct use in 1200 V-class IGBT and SiC MOSFET half-bridge designs without additional level-shifting circuitry.

What are the UVLO thresholds for the SI8231AB-D-IS and how do they affect system behavior during power-up?

The SI8231AB-D-IS has a 5 V UVLO threshold on VDDI, VDDA, and VDDB, with −100 mV hysteresis. During power-up, outputs VOA and VOB remain low until all three supplies exceed 5 V, then follow the PWM input after t_START (≤10 µs). This prevents partial drive activation and ensures deterministic startup in systems with asymmetric supply ramp rates, such as those with separate 5 V logic and 12–15 V gate-drive rails.

Is the SI8231AB-D-IS qualified for automotive applications and what documentation is available?

Yes, the SI8231AB-D-IS is AEC-Q100 qualified and offered in automotive-grade variants (e.g., SI8231AB-AS). It supports AIAG-compliant PPAP documentation, IMDS and CAMDS material declarations, and zero-defect manufacturing flows. These capabilities make SI8231AB-D-IS suitable for automotive applications including onboard chargers, battery management systems, and traction inverters where long-term reliability and supply chain traceability are mandatory.