Comparison: Infineon 1EDN9550BXTSA1 vs STMicroelectronics STGAP2SICSTR Gate Driver ICs
1. Quick verdict
For driving high- and low-side SiC MOSFETs in half-bridge configurations requiring very fast switching and high peak currents, the Infineon 1EDN9550BXTSA1 is the better choice due to its dual-channel, high peak source/sink current (5.2A/9.4A) and ultra-fast 1 ns rise/fall times. For isolated, single-channel gate drive with galvanic isolation up to 5 kVrms and moderate drive current (4A), the STGAP2SICSTR is preferable, especially where system-level isolation and noise immunity (100 V/ns CMTI) are critical, despite its slower switching speed (~30 ns rise/fall).
2. Spec comparison table
| Spec | 1EDN9550BXTSA1 | STGAP2SICSTR | Notes |
|---|---|---|---|
| Channel Type | Dual (High-Side, Low-Side) | Single | Infineon supports half-bridge drive natively; ST is single-channel. Infineon better for half-bridge. |
| Number of Channels | 2 | 1 | Same as above. |
| Technology | Non-isolated, no galvanic isolation | Capacitive Coupling galvanic isolation | ST provides 5 kVrms isolation, critical for safety and noise immunity; Infineon does not isolate. |
| Voltage Supply Range | 4.5 V to 20 V | 3 V to 5.5 V | Infineon supports wider supply voltage, allowing flexible bootstrap voltages; ST limited to 5.5V max. |
| Peak Output Current (Source) | 5.2 A | 4 A | Infineon can source more current, enabling faster gate charging. |
| Peak Output Current (Sink) | 9.4 A | 4 A | Infineon sinks more current, allowing faster turn-off transitions. |
| Rise/Fall Time (typ) | 1 ns / 1 ns | 30 ns / 30 ns | Infineon is an order of magnitude faster, critical for high-speed switching and minimizing transition losses. |
| Operating Temperature Range | -40°C to 150°C (TJ) | -40°C to 125°C | Infineon supports higher junction temperature, beneficial for SiC devices in harsh environments. |
| Package | PG-SOT23-6-3 (SOT-23-6) | 8-SOIC (7.5 mm width) | Infineon is smaller, better for dense layouts; ST is larger but accommodates isolation structure. |
| Logic Input Type | Inverting & Non-inverting | TTL/CMOS with hysteresis (3.3V/5V) | ST input logic includes hysteresis for noise immunity; Infineon supports both input polarities. |
| Max High-Side Voltage (Bootstrap) | 400 V | Not specified | Infineon supports high bootstrap voltage for high-voltage half-bridge; ST not specified. |
| Isolation Voltage (Vrms) | None | 5000 Vrms | ST provides galvanic isolation, essential for isolated power stages or reinforced insulation. |
| Common Mode Transient Immunity | Not specified | 100 V/ns | ST explicitly rated for high CMTI, important in noisy power stages. |
| Propagation Delay (max) | Not specified | 90 ns (tplh, tphl) | ST has significant delay; Infineon likely much faster but not explicitly stated. |
| Pulse Width Distortion (max) | Not specified | 20 ns | ST’s PWD is moderate; Infineon likely better but not specified. |
| Supply Current (typical) | Not specified | ~1.8 mA quiescent; 400-550 µA standby | ST datasheet includes detailed current consumption; Infineon does not specify in source data. |
| Maximum Switching Frequency | Not specified | 1 MHz | ST limited to 1 MHz max switching, suitable for many but not all SiC applications. |
| Mounting Type | Surface Mount | Surface Mount | Both SMT for compact, automated assembly. |
| Input Voltage Max | Not specified | 26 V | ST input tolerant up to 26 V, flexible for various logic levels. |
| Safe Clamp Voltage | Not specified | 2.0 - 2.3 V | ST includes Miller clamp feature, reducing false turn-on in half-bridge operation. |
| Thermal Resistance (Junction-to-Ambient) | Not specified | 120 °C/W (typ) | ST thermal resistance typical, useful for thermal design; Infineon data not provided here. |
| Storage Temperature Range | Not specified | -40°C to 150°C | Both support wide storage temp. |
| Approval Agency | Not specified | UL | ST has UL approval, relevant for safety certifications. |
3. Design trade-offs
The Infineon 1EDN9550BXTSA1 is designed for high-performance SiC MOSFET gate drive in compact half-bridge configurations. Its dual-channel output and very high peak drive currents (up to 9.4A sink) allow for extremely fast switching transitions (1 ns rise/fall), which reduce switching losses and improve efficiency in high-frequency applications. The wider supply voltage range (4.5–20 V) supports bootstrap operation for high-side drive and flexible gate voltage tuning. Its small SOT-23-6 package enables dense PCB layouts but may require careful thermal management given the high transient currents and potential power dissipation.
In contrast, the STGAP2SICSTR employs capacitive coupling technology for galvanic isolation, rated for 5 kVrms, which is critical in applications requiring reinforced isolation or where safety standards mandate physical isolation between control and power circuits. The isolation comes at the cost of slower switching speeds—typical rise/fall times of 30 ns and propagation delays up to 90 ns—which can increase switching losses and limit maximum switching frequency to about 1 MHz. The driver supports a single channel and is housed in a larger SOIC-8 package to accommodate isolation structures, making it less suitable for space-constrained designs but better for system-level isolation and noise immunity.
From a layout perspective, the Infineon device requires bootstrap circuitry and careful high-side supply design but benefits from a smaller footprint and higher switching speed. The ST device requires careful routing of isolation boundaries and decoupling capacitors on both sides of the barrier. The ST’s input logic hysteresis and Miller clamp feature help mitigate noise-induced false switching, which is valuable in electrically noisy environments.
Thermally, Infineon’s higher junction temperature rating (up to 150°C) offers more headroom in demanding environments. ST’s 125°C limit is typical for isolated drivers but requires attention to derating curves due to the thermal resistance of 120 °C/W (typical), which is relatively high and may require heat sinking or derating in high ambient temperatures.
Cost-wise, the Infineon’s smaller package and simpler non-isolated design generally translate to lower BOM cost for non-isolated half-bridge stages. The ST’s isolation and larger package add complexity and cost but may eliminate the need for separate isolation transformers or optocouplers, simplifying system design and certification.
4. Use-case fit
Choose 1EDN9550BXTSA1 when…
- Designing a compact, non-isolated half-bridge gate driver for SiC MOSFETs where very fast switching is critical (e.g., >100 kHz switching, resonant or hard switching topologies).
- High peak gate drive current (up to 9.4A sink) is needed to minimize switching losses and reduce gate charge time.
- Operation at elevated junction temperatures (up to 150°C) is expected, such as in automotive or industrial power stages.
- Board space is limited and a small SOT-23-6 package is required.
- The system power stage voltage does not require galvanic isolation (e.g., low-voltage DC-DC converters or integrated power modules).
Choose STGAP2SICSTR when…
- Galvanic isolation of 5 kVrms is mandatory for system safety, regulatory compliance, or noise immunity (e.g., grid-tied inverters, isolated motor drives).
- Single-channel isolated gate drive is needed for isolated half-bridge or high-side drive with external isolated power.
- System-level noise immunity is essential, requiring a device with 100 V/ns common mode transient immunity and input hysteresis.
- Switching frequencies are moderate (up to 1 MHz) and ultra-fast switching transitions are not the primary concern.
- The design benefits from integrated Miller clamp and built-in safe clamp voltage to reduce false turn-on and enhance robustness in half-bridge configurations.
5. Drop-in compatibility
These two devices are not pin- or footprint-compatible. The Infineon 1EDN9550BXTSA1 is a dual-channel driver in a small SOT-23-6 package, intended for direct high-side/low-side gate drive with bootstrap supply. The STGAP2SICSTR is a single-channel isolated driver in a larger SOIC