STGAP1BS - 4A Galvanically Isolated Single Gate Driver | STMicroelectronics
MPN: STGAP1BS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.45 | $3.45 |
| 10 | $3.1 | $31.00 |
| 100 | $2.76 | $276.00 |
| 500 | $2.48 | $1,240.00 |
| 1,000 | $2.21 | $2,210.00 |
STGAP1BS Overview
A gate driver is a power amplifier that accepts a low-power input from a controller IC and produces a high-current drive output to control the gate of a power transistor. In the hierarchy of power electronics, a gate driver sits between the control stage (microcontroller or DSP) and the power stage (IGBT or MOSFET), ensuring fast and reliable switching. The STGAP1BS integrates a galvanic isolation barrier, which separates the input and output grounds, protecting the low-voltage control circuitry from high-voltage transients and ground loops.
Key features of the STGAP1BS include a 4A peak output current, 4 kV galvanic isolation, 100 V/ns common-mode transient immunity (CMTI), and a wide supply voltage range from 4.5V to 18V on the output side. The device also features a Miller clamp function to prevent spurious turn-on during high dv/dt events, and a desaturation protection input for overcurrent detection. These features make it ideal for driving SiC MOSFETs and IGBTs in high-frequency, high-efficiency power converters.
The STGAP1BS uses STMicroelectronics' proprietary galvanic isolation technology, which provides robust isolation with low propagation delay (typically 75 ns) and tight part-to-part matching. The device supports both bipolar and unipolar supply configurations, allowing flexible design for various gate drive requirements. The wide-body SO-8W package ensures adequate creepage and clearance distances for 4 kV isolation, meeting IEC 60747-17 requirements.
Typical applications include motor drives for industrial automation, solar inverters, uninterruptible power supplies (UPS), and electric vehicle (EV) charging stations. The STGAP1BS is also suitable for welding equipment and induction heating systems, where high reliability and fast switching are critical.
When designing with the STGAP1BS, ensure proper PCB layout to minimize parasitic inductance in the gate drive loop. Use a low-ESR capacitor close to the VCC and GND pins to supply the high peak currents. The Miller clamp pin should be connected to the gate of the power transistor with a short, low-inductance trace to effectively suppress dv/dt-induced turn-on.
Drop-in alternatives for STGAP1BS — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
STGAP1AS
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
STGAP2S
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
STGAP1BS Maximum Ratings & Electrical Characteristics
| Output Peak Current | 4 A (source/sink) |
| Galvanic Isolation | 4 kV |
| Common-Mode Transient Immunity (CMTI) | 100 V/ns |
| Propagation Delay | 75 ns (typical) |
| Output Supply Voltage | 4.5 V to 18 V |
| Input Supply Voltage | 3.3 V to 5 V |
| Miller Clamp | Yes |
| Desaturation Protection | Yes |
| Operating Temperature | -40C to +125C |
| Package | SO-8W (wide body) |
| Mounting Type | Surface Mount |
| Isolation Standard | IEC 60747-17 |
| RoHS Status | Compliant |
| AEC-Q100 | Not qualified (standard grade) |
| Output Configuration | Single channel, isolated |
STGAP1BS Pin Configuration
| Pin 1 | VCC — Input supply voltage (3.3V to 5V) |
| Pin 2 | GND1 — Input ground |
| Pin 3 | IN — Input control signal |
| Pin 4 | EN — Enable input (active high) |
| Pin 5 | GND2 — Output ground |
| Pin 6 | OUT — Gate drive output |
| Pin 7 | VCC2 — Output supply voltage (4.5V to 18V) |
| Pin 8 | CLAMP — Miller clamp output |
Typical Applications
STGAP1BS is suitable for 6 applications: Motor Drives, Solar Inverters, Uninterruptible Power Supplies (UPS), EV Charging Stations, Welding Equipment, Induction Heating.
Motor Drives
The STGAP1BS is ideal for motor drives in industrial automation, providing 4A peak current to drive IGBTs and SiC MOSFETs in inverters. Its 4kV isolation protects control circuitry from high-voltage transients, while the Miller clamp prevents spurious turn-on during high dv/dt events. The low propagation delay (75 ns) ensures precise switching, reducing motor torque ripple and improving efficiency. In a typical motor drive, the STGAP1BS is placed between the microcontroller and the power stage, with its output connected to the gate of the IGBT. The desaturation protection monitors the collector-emitter voltage to detect overcurrent conditions, triggering a fault signal to the controller. The wide output supply range (4.5V to 18V) allows compatibility with various gate drive voltages. Compared to non-isolated drivers, the STGAP1BS eliminates ground loops and improves noise immunity, making it suitable for high-power motor drives in noisy industrial environments.
Recommended
Solar Inverters
The STGAP1BS is well-suited for solar inverters, where high efficiency and reliability are paramount. Its 4A peak output current enables fast switching of SiC MOSFETs, reducing switching losses and improving inverter efficiency. The 4kV isolation ensures safe operation in high-voltage DC bus systems, while the high CMTI (100 V/ns) maintains signal integrity in the presence of fast voltage transients. In a solar inverter, the STGAP1BS drives the gate of the SiC MOSFET in a boost converter or full-bridge topology. The desaturation protection provides overcurrent protection, preventing damage to the power stage. The wide operating temperature range (-40C to +125C) allows operation in outdoor environments. Compared to optocoupler-based drivers, the STGAP1BS offers lower propagation delay and higher CMTI, making it suitable for high-frequency switching (up to several hundred kHz) in modern solar inverters.
Recommended
Uninterruptible Power Supplies (UPS)
The STGAP1BS is used in UPS systems to drive IGBTs in the inverter stage, providing reliable power backup. Its 4A peak output current ensures fast switching, reducing losses and improving efficiency. The 4kV isolation protects the control circuitry from high-voltage transients, while the Miller clamp prevents spurious turn-on during load transients. In a UPS, the STGAP1BS is used in the DC-AC inverter stage, driving the IGBTs in a half-bridge or full-bridge configuration. The desaturation protection detects overcurrent conditions, triggering a fault signal to the controller to shut down the inverter. The wide output supply range allows flexible design for different gate drive voltages. Compared to non-isolated drivers, the STGAP1BS provides better noise immunity and safety, making it suitable for high-power UPS systems.
Recommended
EV Charging Stations
The STGAP1BS is suitable for EV charging stations, where high-power conversion and reliability are critical. Its 4A peak output current drives SiC MOSFETs in the power stage, enabling high-efficiency charging. The 4kV isolation ensures safe operation in high-voltage systems, while the high CMTI maintains signal integrity in noisy environments. In an EV charging station, the STGAP1BS is used in the AC-DC and DC-DC converters, driving the power transistors. The desaturation protection provides overcurrent protection, preventing damage to the power stage. The wide operating temperature range allows operation in outdoor charging stations. Compared to optocoupler-based drivers, the STGAP1BS offers lower propagation delay and higher CMTI, making it suitable for high-frequency switching in modern charging systems.
Recommended
Welding Equipment
The STGAP1BS is used in welding equipment to drive IGBTs in the inverter stage, providing precise control of the welding current. Its 4A peak output current ensures fast switching, reducing losses and improving weld quality. The 4kV isolation protects the control circuitry from high-voltage transients, while the Miller clamp prevents spurious turn-on during high dv/dt events. In a welding machine, the STGAP1BS drives the IGBTs in a full-bridge inverter, with the output connected to the gate of the IGBT. The desaturation protection detects overcurrent conditions, triggering a fault signal to the controller. The wide output supply range allows flexible design for different gate drive voltages. Compared to non-isolated drivers, the STGAP1BS provides better noise immunity and safety, making it suitable for harsh welding environments.
Recommended
Induction Heating
The STGAP1BS is ideal for induction heating systems, where high-frequency switching and high reliability are required. Its 4A peak output current enables fast switching of IGBTs, reducing losses and improving heating efficiency. The 4kV isolation ensures safe operation in high-voltage resonant circuits, while the high CMTI maintains signal integrity in the presence of fast voltage transients. In an induction heater, the STGAP1BS drives the IGBTs in a resonant inverter, with the output connected to the gate of the IGBT. The desaturation protection provides overcurrent protection, preventing damage to the power stage. The wide operating temperature range allows operation in high-temperature environments. Compared to optocoupler-based drivers, the STGAP1BS offers lower propagation delay and higher CMTI, making it suitable for high-frequency switching (up to several hundred kHz) in induction heating systems.
Recommended
Recommended Products Summary
Engineering reference data for STGAP1BS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | STGAP1AS | STGAP2S | UCC21520 | Si8271 |
|---|---|---|---|---|---|
| Package | SO-8W | SO-8W (same) | SO-8W (same) | SOIC-16 (different) | SOIC-8 (different) |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | Texas Instruments | Silicon Labs |
| Output Peak Current | 4 A | 4 A | 4 A | 4 A | 4 A |
| Galvanic Isolation | 4 kV | 4 kV | 4 kV | 5.7 kV | 2.5 kV |
| CMTI | 100 V/ns | 100 V/ns | 100 V/ns | 100 V/ns | 200 V/ns |
| Propagation Delay | 75 ns | 75 ns | 75 ns | 30 ns | 60 ns |
| Miller Clamp | Yes | Yes | Yes | No | No |
| Desaturation Protection | Yes | Yes | Yes | No | No |
| AEC-Q100 | No | Yes | No | No | No |
Key Differentiators
- Integrated Miller clamp (vs UCC21520)
- Integrated desaturation protection (vs Si8271)
- AEC-Q100 qualified variant available (vs STGAP1AS)
Design Notes
Place a low-ESR ceramic capacitor (e.g., 100 nF) as close as possible to the VCC2 and GND2 pins to supply the high peak currents during switching. Additionally, a 10 uF electrolytic capacitor should be placed nearby to handle the average current. The gate drive loop (OUT to gate, and GND2 to source/emitter) should be kept as short and wide as possible to minimize parasitic inductance, which can cause voltage overshoot and ringing.
The STGAP1BS dissipates power primarily during switching due to the gate charge of the power transistor. For high-frequency operation, ensure adequate copper area on the PCB to dissipate heat. The SO-8W package has a thermal resistance of approximately 100 C/W (theta_JA). For continuous operation at high switching frequencies, consider adding thermal vias under the package to improve heat transfer to the ground plane.
Do not exceed the absolute maximum ratings for VCC2 (18V) and VCC (5V). Ensure the input signal is within the specified logic levels. The Miller clamp pin should be connected to the gate of the power transistor with a short, low-inductance trace to effectively suppress dv/dt-induced turn-on. If the desaturation protection is not used, connect the DESAT pin to GND2 through a resistor to avoid false triggering.
Compliance Information
RoHS compliant per ST datasheet. Not AEC-Q100 qualified; use STGAP1AS for automotive.
