Skyworks Solutions Inc. SI8235BB-D-IM

Overview

SI8235BB-D-IM from Skyworks Solutions is a dual-channel isolated gate driver IC with 4.0 A peak output current per channel, 2.5 kVRMS input-to-output isolation, and SOIC-16 narrow-body package. It features independent TTL-compatible inputs (VIA/VIB), no internal dead time, and operates across –40°C to +125°C for industrial motor control and isolated DC-DC power supplies.

For engineers reviewing the SI8235BB-D-IM datasheet, SI8235BB-D-IM pinout, SI8235BB-D-IM application, or SI8235BB-D-IM equivalent, key selection criteria include its dual-driver configuration (no HS/LS overlap logic), 2.5 kVRMS isolation rating, 8 V UVLO threshold, and compatibility with 4.0 A MOSFET/IGBT gate drive in space-constrained layouts.

Technical Context

The SI8235BB-D-IM implements two fully isolated RF-modulated channels using Skyworks' proprietary silicon isolation barrier, enabling independent high-side and low-side gate drive without shared ground constraints. Each channel supports up to 8 MHz switching frequency and delivers 4.0 A peak source/sink current into capacitive loads.

Unlike HS/LS variants (e.g., SI8233BB-D-IS), this dual-driver version lacks programmable dead time and overlap protection - outputs respond immediately to input transitions with no inter-channel timing coordination. Input logic is TTL-compatible with >400 mV hysteresis, and undervoltage lockout triggers at 8 V on VDDI, VDDA, and VDDB independently.

Key Specifications

Pinout & Package

SI8235BB-D-IM uses a RoHS-compliant SOIC-16 narrow-body package (5.3 mm width, 10.3 mm length, 1.75 mm height) with creepage ≥5.5 mm and clearance ≥5.5 mm per IEC60664-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SI8235BD-D-IS, SI8235BB-D-IM offers reduced board space and lower cost for 250 VAC-rated systems, while UCC21520DWR provides superior noise rejection at the expense of layout complexity and supply routing overhead.

Availability

SI8235BB-D-IM is available at Aetrix Electronics and suitable for motor control systems, isolated dc-dc power supplies, and solar inverters requiring stable component supply with guaranteed long-term sourcing.

Supply support for SI8235BB-D-IM 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 for infrastructure, automotive, and industrial markets.

The Si823x family was designed specifically for robust, high-speed isolated gate driving in power conversion systems - emphasizing low propagation delay, high noise immunity, and simplified system-level isolation architecture.

FAQ

What is the maximum switching frequency supported by the SI8235BB-D-IM?

The SI8235BB-D-IM supports up to 8 MHz switching frequency, enabled by its ≤30 ns maximum propagation delay and fast 4.0 A gate drive capability. This allows clean PWM edge integrity even with heavy gate capacitance loads, making it suitable for high-frequency resonant converters and digital power controllers. The actual usable frequency depends on external gate resistor selection and MOSFET/IGBT Qg.

Does the SI8235BB-D-IM include built-in dead time or overlap protection?

No, the SI8235BB-D-IM does not include programmable dead time or overlap protection - it is a dual-driver variant (not HS/LS), so VOA and VOB respond independently to VIA and VIB with no inter-channel timing coordination. Dead time must be implemented externally in the controller logic. This differs from SI8233BB-D-IS, which integrates programmable DT and overlap recovery.

Can the SI8235BB-D-IM drive both high-side and low-side switches in a half-bridge configuration?

Yes, the SI8235BB-D-IM can drive both high-side and low-side switches in a half-bridge, but only when used with external bootstrap or isolated DC-DC supplies for VDDA and VDDB. VOA is referenced to GNDA and VOB to GNDB, allowing independent floating operation - however, unlike dedicated HS/LS drivers, it provides no internal timing coordination between channels.

What is the purpose of the DISABLE pin on the SI8235BB-D-IM?

The DISABLE pin on the SI8235BB-D-IM is an active-high global shutdown input that forces both VOA and VOB low within tSD (typ. 100 ns), overriding all input states. It remains effective only when VDDI is above UVLO (8 V); if VDDI falls below UVLO, outputs default low regardless of DISABLE state. This enables fast fault response in overcurrent or overtemperature conditions.

Is the SI8235BB-D-IM qualified for automotive applications?

No, the SI8235BB-D-IM is an industrial-grade part (suffix "-I"). Automotive qualification requires the "-A" suffix (e.g., SI8235BB-D-AM), which undergoes full AEC-Q100 stress testing, PPAP documentation, and IMDS/CAMDS compliance. SI8235BB-D-IM is rated for –40°C to +125°C but lacks automotive-specific process controls and failure analysis reporting.