Semikron SKHI 24R | Robust Gate Driver for 1200V/1700V IGBT Modules
The Semikron SKHI 24R is a hybrid gate driver engineered for power electronics engineers who demand uncompromising reliability and precise control over high-power IGBT modules. This driver isn't merely a switching component; it's an integrated protection and control system designed to safeguard your investment in expensive power semiconductors and ensure maximum system uptime in demanding industrial applications.
Product Highlights: The Engineer's Advantage
- Enhanced System Survivability: Features integrated short-circuit protection via VCEsat monitoring, which detects fault conditions and initiates a safe shutdown within microseconds to prevent IGBT failure.
- Controlled Shutdown Under Fault: The "soft turn-off" feature intelligently manages the shutdown sequence during a short-circuit event, mitigating dangerous voltage overshoots (dV/dt) that can destroy the IGBT.
- Simplified Diagnostics: An isolated error signal (Fault output) provides clear, direct feedback to the system controller, streamlining fault logging and reducing troubleshooting time in the field.
- Wide Application Window: Optimized for driving 1200V and 1700V IGBTs, making the SKHI 24R a versatile solution for a broad range of high-voltage inverters, motor drives, and power supplies.
Technical Deep Dive: Beyond Simple Switching
The true value of the SKHI 24R lies in its sophisticated, integrated protection mechanisms. These are not just add-on features; they are core to its design philosophy, providing a level of control that discrete solutions struggle to match.
VCEsat Monitoring and Short-Circuit Protection
During the on-state, the driver continuously monitors the IGBT's collector-emitter saturation voltage (VCE(sat)). In a short-circuit scenario, the IGBT exits saturation, causing VCE to rise rapidly. The SKHI 24R detects this voltage increase, cross-referencing it against a predefined threshold. Once the fault is confirmed, it immediately initiates a shutdown, typically within 10µs—a critical timeframe for preventing catastrophic failure. This proactive monitoring is the first line of defense for your power stage.
Soft Turn-Off and Overvoltage Suppression
Simply turning off an IGBT during a high-current fault is dangerous. The stray inductance in the power circuit can induce massive voltage spikes (V = L * di/dt), leading to avalanche breakdown. The SKHI 24R’s "soft turn-off" function intelligently addresses this. Instead of abruptly cutting the gate voltage to zero or negative, it reduces it in a controlled manner. This increases the turn-off time slightly but dramatically reduces the rate of current change (di/dt), keeping the overvoltage spike within the IGBT's Safe Operating Area (SOA).
Key Parameter Overview for System Design
The following table outlines the critical performance specifications for the Semikron SKHI 24R, providing essential data for circuit integration and performance simulation.
| Parameter | Value / Specification |
|---|---|
| Compatible IGBT Voltage Class | 1200V / 1700V |
| Peak Output Current (Iout peak) | ±15 A |
| Switching Frequency (fsw) | Up to 20 kHz |
| Protection Features | VCEsat Monitoring, Soft Turn-Off, Undervoltage Lockout (UVLO) |
| Isolation Test Voltage (Visol) | 4000 V (RMS, 1 min) |
| Logic Supply Voltage (VCC) | +15 V (±10%) |
For detailed electrical characteristics and application notes, you can download the official SKHI 24R datasheet.
Frequently Asked Questions (FAQ)
What is the primary benefit of the isolated "Fault" signal?
The isolated fault output is a critical feature for system-level integration. It allows the driver, operating at the high potential of the power circuit, to communicate a fault condition back to a ground-referenced microcontroller without the need for external, high-voltage optocouplers. This simplifies the control board design, reduces component count, and provides a noise-immune signal for initiating system-wide safety protocols or alerting the operator.
Is the SKHI 24R suitable for driving paralleled IGBTs?
The SKHI 24R is a single-channel driver designed to drive a single IGBT module or a set of co-packaged IGBTs. While it can be used in systems with paralleled modules, the best practice for robust gate drive design is to use one driver per module. This ensures that the VCEsat protection monitors each module individually, preventing a situation where a single failing module goes undetected and causes a cascading failure in the other paralleled devices. For designs requiring a single driver for multiple paralleled modules, please contact our technical team to discuss alternative solutions.
