IN Brief:
- The GANSPIN1102, GANSPIN1102E, and GANSPIN1105 integrate two 100V GaN transistors, gate-drive circuitry, and associated protection functions.
- Typical transistor on-resistance values are 2.4mΩ or 5.5mΩ, with the GANSPIN1102E providing a dedicated top-side-cooling arrangement.
- The devices support current ratings of up to 60A depending on configuration, with commercial availability expected by the end of 2026.
STMicroelectronics has expanded its GANSPIN motor-driver family with three 100V gallium nitride devices designed for compact, high-current motion-control applications, including industrial actuators, robotic joints, drones, and electrically powered equipment.
The GANSPIN1102, GANSPIN1102E, and GANSPIN1105 combine two GaN power transistors with integrated gate-drive circuitry and protection functions. All three devices use a 5 × 6.5mm package, with different on-resistance characteristics and a dedicated top-side-cooling arrangement available for applications requiring additional thermal management.
The GANSPIN1102 provides a typical transistor on-resistance of 2.4mΩ, while the GANSPIN1105 has a typical value of 5.5mΩ. The GANSPIN1102E combines the lower-resistance configuration with a package designed to transfer heat through its upper surface.
ST specifies continuous output-current capability reaching 60A, depending on the selected device. The maximum current must be assessed against the relevant operating and thermal conditions rather than treated as a rating that can be sustained in every circuit arrangement.
The devices target motor drives in which the available space for power electronics is limited. Robotic joints, for example, may contain a motor, position-sensing components, control electronics, and mechanical transmission elements within a confined enclosure.
Integrating the power transistors and their gate-drive circuits can reduce the number of external components and the PCB area required for the switching stage. It can also shorten critical electrical connections, although the resulting layout still requires careful attention to switching behaviour, current distribution, and heat removal.
Gallium nitride transistors can offer low conduction resistance and rapid switching compared with conventional silicon alternatives under suitable operating conditions. Their use can reduce losses and support compact converter designs, but performance depends on the electrical load, switching frequency, operating voltage, and selected circuit topology.
Motor inverters regulate electrical power by switching semiconductor devices in a controlled sequence. In a three-phase motor drive, several half-bridge circuits are used to apply the required voltage patterns to the motor windings, with the controller adjusting switching behaviour in response to torque and speed requirements.
Each half-bridge contains two power transistors connected between the supply rails. Coordinating their switching allows the output node to be driven towards different voltage levels, forming the electrical waveforms required by the motor-control algorithm.
The two transistors must not conduct simultaneously in a manner that creates a direct low-impedance path across the supply. This condition, known as shoot-through, can produce damaging current and requires appropriate gate-drive timing and protection.
Conventional control methods introduce a short dead time between switching events to reduce the risk of simultaneous conduction. During this interval, current may continue flowing through alternative paths within the power stage, contributing to losses whose magnitude depends on the semiconductor technology and operating conditions.
GaN devices have reverse-conduction characteristics that differ from those of conventional silicon MOSFETs. Excessive dead time can therefore increase losses associated with third-quadrant operation, while insufficient separation between switching events can increase the risk of unwanted conduction overlap.
The new GANSPIN devices incorporate smart shoot-through protection that monitors gate-drive output voltage. ST has designed the function to permit very short dead times while guarding against simultaneous conduction, allowing the switching sequence to be adjusted without relying solely on fixed timing margins.
The integrated gate drivers provide separate controls for transistor turn-on and turn-off behaviour. This gives designers a means of adjusting switching transitions to balance electrical efficiency, electromagnetic interference, and the requirements of the connected motor-control circuit.
ST specifies a propagation delay of approximately 20ns and delay matching of 1ns. The devices support switching frequencies up to 5MHz under their stated operating specifications, although this represents a hardware capability rather than a recommended operating frequency for every motor inverter.
Practical pulse-width modulation frequencies depend on motor inductance, control bandwidth, switching losses, audible noise, electromagnetic compatibility, and thermal performance. Increasing frequency can improve aspects of current control or reduce the size of selected passive components, but it also increases the number of switching events during each operating period.
Each switching event can dissipate energy as transistor voltage and current change. Consequently, a higher switching frequency does not necessarily produce a more efficient motor drive, even when the semiconductor devices are capable of rapid transitions.
The GANSPIN1100 devices integrate optimised gate resistance, VCC and bootstrap capacitors, and associated circuitry required to operate the switching stage. A dynamic bootstrap switch is intended to maintain suitable high-side gate-drive conditions while preventing bootstrap capacitor overcharging.
Additional protection functions include input interlocking, undervoltage and overvoltage lockout on the relevant supplies, and thermal shutdown. These functions address specified fault conditions within the integrated driver, but they do not replace application-level current limiting, supply protection, or the thermal supervision required by a complete motor-control system.
Thermal management becomes especially important where substantial current passes through a compact semiconductor package. Conduction losses increase with the square of current for a given resistance, while switching losses contribute additional heat that must be transferred away from the active semiconductor junctions.
The GANSPIN1102E provides a dedicated top-side-cooling arrangement, allowing heat to be conducted towards an appropriate thermal interface or cooling structure above the device. Its effectiveness depends on the package contact, surrounding mechanical design, and the thermal resistance of the completed assembly.
All three devices use land grid array packages approximately 1.12mm high, with an operating junction temperature range from -40°C to 125°C. ST states that their pinout can support optimised layouts using two-layer PCBs, although high-current routing, electrical clearance, and electromagnetic interference must be assessed for each application.
The devices extend ST's existing GANSPIN portfolio towards compact 100V motor-control applications. The company separately supplies higher-voltage integrated GaN stages for other power conversion requirements, reflecting the different voltage and power conditions encountered across the motor-drive market.
Commercial availability is expected by the end of 2026, with indicative pricing starting at $1.65 for quantities of 1,000 pieces. The company has not identified a production customer or disclosed application-specific efficiency measurements for the new devices.
ST will demonstrate the GANSPIN1102E driving robotic arm joints at electronica 2026 in Munich from 10 to 13 November. The demonstration will provide an example of the integration and cooling approach, while production equipment designs will still require validation of switching behaviour, current capacity, electromagnetic compatibility, and thermal reliability under their intended operating conditions.
