The OptiMOS 6 40 V MOSFET - Infineon bets on efficient drive systems

OptiMOS 6 40 V MOSFET reaches single-digit milliohm on?resistance for compact motor control boards. This product is driving the price of Infineon Technologies AG stock (ISIN DE0006231004).

OptiMOS 6 40 V MOSFET lands on the workbench as a thumbnail-sized black package, cold to the touch before the first switching pulse runs through it. When senior product manager Markus Holzner clicks the lab supply on, the tiny Infineon chip quietly starts moving a brushed DC motor without even warming the air around it.

Efficient 40 V MOSFET for drives

Infineon Technologies sells the OptiMOS 6 40 V MOSFET family as its latest generation of low-voltage power transistors for automotive and industrial applications. These N-channel MOSFETs target 12 V and 24 V systems such as electric power steering, pumps and industrial motor drives. With typical RDS(on) values down in the single-digit milliohm range, they cut conduction losses compared to previous OptiMOS generations.

The devices use Infineon’s sixth-generation trench MOSFET technology optimized for low resistance and fast switching while keeping gate charge under control. Engineers can choose from packages like SuperSO8, PG-TDSON-8 and larger D²PAK for higher current needs. In a compact SuperSO8, some variants carry continuous drain currents beyond 100 A, which matters when a compact inverter board has to sit right next to the motor housing.

Targeting automotive and industrial customers

Infineon positions OptiMOS 6 40 V clearly at designers of automotive ECUs and industrial controllers, rather than end consumers. Typical data sheets cite use cases such as electric power steering, braking actuators, transmission control and fuel or water pumps in vehicles, plus forklifts and other industrial vehicles. In those environments, the MOSFET must handle high current pulses, repetitive switching and harsh ambient temperatures without drift.

Automotive-grade variants are qualified according to AEC-Q101, meaning they go through stress tests that include temperature cycling, humidity exposure and high-temperature reverse bias. That qualification is essential for Tier-1 suppliers who integrate these chips onto boards sitting in engine compartments. System designers appreciate that Infineon offers matched MOSFETs in half-bridge or multi-phase topologies, simplifying layout for three-phase motor control.

Data sheets and design support

On Infineon’s product page for power MOSFETs, the OptiMOS 6 40 V range appears alongside older OptiMOS generations and StrongIRFET parts. Interested engineers can filter by voltage, package and RDS(on) to find a specific ordering code that fits their design. Each code comes with a PDF data sheet listing parameters such as drain-source breakdown voltage, continuous current, on-resistance at different gate voltages and switching times.

Infineon complements the bare data with application notes and reference designs that show how to lay out a motor control board. A typical reference design features several OptiMOS devices arranged in three half-bridges, gate drivers, current shunts and a microcontroller. PCB layouts highlight thermal vias under the MOSFET’s drain pad and copper pours to spread heat. That visual guidance helps designers avoid hotspots that could otherwise be felt as a warm patch on the back side of an assembled board after a long duty cycle.

Performance and thermal behavior

Performance marketing around OptiMOS 6 focuses on lower on-resistance per die area compared to competitors and previous Infineon families. Lower RDS(on) directly reduces I²R losses in the conduction phase, which is critical when a motor spends most of its time under load. The devices also aim at reduced switching losses through optimized gate charge and output capacitances. In practice, this means less wasted energy and cooler housings, which can be felt as only a slight warmth on the plastic case instead of a hot surface.

In automotive-qualified variants, the maximum junction temperature often extends to 175 °C, giving margin for operation in high ambient temperatures. Infineon provides thermal resistance data so designers can calculate temperature rise at given currents. Combined with appropriate heat sinking, the MOSFET can switch hundreds of amps in short pulses without crossing its safe operating area. For engineers, that calculation is not theoretical; it decides whether a steering assist ECU survives a summer traffic jam.

Packaging, variants and availability

OptiMOS 6 40 V MOSFETs come in multiple package families that balance board space and thermal performance. SuperSO8 and PG-TDSON-8 packages suit compact ECUs where low profile is crucial. Larger D²PAK and TO-220 style packages remain relevant in industrial drives that still rely on through-hole mounting and heat sinks. Infineon often offers the same die technology in several packages at different current ratings, so the same design philosophy can scale from a small pump to a bigger compressor.

According to distributor listings, OptiMOS 6 40 V parts are available through major electronics channels such as Digi-Key, Mouser and Farnell, with unit pricing dependent on package, RDS(on) and order volume. For example, a mid-range OptiMOS 6 40 V MOSFET in a SuperSO8 package may sell in the range of a few euros per piece in low quantities, dropping to well below one euro for tens of thousands of units. Automotive customers typically agree on long-term supply contracts directly with Infineon.

Competition and design choices

Infineon faces strong competition in low-voltage MOSFETs from players like Nexperia, STMicroelectronics and Vishay, who offer their own trench MOSFET families. Engineers comparing data sheets look beyond headline RDS(on) and assess gate charge, output capacitance and body diode behavior. They also evaluate how consistent parameters are across temperature and production lots. In conversations with design teams, Holzner often hears that reliable sourcing and stable parameters across years can outweigh a marginal RDS(on) advantage.

For many board designers, choosing OptiMOS 6 40 V is as much about ecosystem as about single parts. Infineon combines power MOSFETs with gate driver ICs and microcontrollers, plus simulation tools in its IPOSIM environment. That ecosystem allows engineers to simulate a motor control design before sending boards to fabrication. When a prototype finally spins a motor on the bench, the measured currents and temperatures ideally match earlier simulations, saving expensive design loops.

Role in Infineon’s business and stock context

Within Infineon, low-voltage power MOSFETs like OptiMOS 6 40 V sit in the company’s Automotive and Industrial Power Control segments. The family itself is one line among dozens, but high-volume design wins in electric power steering, pumps or industrial vehicles translate into recurring chip shipments over vehicle lifetimes. That revenue stream supports Infineon’s broader positioning as a supplier for electrification and efficient power conversion in cars, factories and renewable energy systems.

On Xetra, Infineon Technologies AG stock reflects investor expectations around such product lines and their role in e-mobility and industrial electrification demand, even though no single MOSFET family dominates the valuation.

Key facts on OptiMOS 6 40 V MOSFET

• Product: OptiMOS 6 40 V MOSFET
• Manufacturer: Infineon Technologies AG
• Category: B2B / Pro line low-voltage power MOSFET
• Market launch: Progressive introduction during the 2020s, with new variants added in recent years
• MSRP / Price: Typically a few euros per unit in low quantities, with volume discounts
• Availability: Distributed globally via major electronics distributors and direct supply agreements
• Target group: Automotive and industrial electronics designers, Tier-1 suppliers, motor control engineers
• Highlight / USP: Very low on-resistance in compact packages for 12 V and 24 V drive systems