Transformer driver simplifies high voltage system designs

In driving up efficiency we are more regularly interacting with high-voltage and high-power electronics. Whether it is renewable power, battery energy storage systems (BESS) and e-meters, electric (EV) vehicles and EV changing stations, or just refrigerators, washing machines, and ovens, the number of power systems that play an integral role in our daily lives has increased significantly. To protect us, as well as the sensitive control electronics used by these systems, power systems need to be reliably isolated. That’s where Nexperia’s new galvanic isolation portfolio comes to the fore, with Nexperia’s transformer driver ICs providing isolated power while simplifying system design and meeting industry standards.

Galvanic isolation is a crucial component in ensuring safety, efficiency, and reliability of modern electronic systems. It refers to the separation of electrical circuits to prevent current flow between them, typically achieved using digital isolators, optocouplers, or other isolated interfaces, while still allowing communications between the circuits. Isolated interfaces require separate, isolated power supplies for each side of the device.

Using the same power supply for both sides would short the isolation barrier, resulting in the system losing the benefits of isolation. If an additional power supply separate from the main power supply is not readily available, then a new, isolated power supply can be created by using a transformer and a transformer driver. The transformer provides the isolation, while the transformer driver uses the main power supply to drive the isolation transformer. With this solution, isolated power can be achieved from a single power source.

NXF650x transformer drivers: efficient, flexible and EM compliant

Designed to deliver low noise and low EMI for isolated power supplies in small form factors are Nexperia’s AEC-Q100 qualified NXF650x.family of specialized push-pull transformer drivers. They can drive low-profile, center-tapped transformers from a 2.25 V to 5 V DC power supply. These devices are highlighted by their high output drive and efficiency, low radiated emissions, and fail-safe I/O.

  • Deliver up to 6 W of power at up to 90% efficiency 
    Compared to other transformer driver topologies, these devices can deliver up to 6 W of power at 90% efficiency in a small, SOT-23 package. These highly efficient small-form-factor devices are ideal for reducing system costs and improving reliability in automotive and industrial applications that require size-sensitive devices.
  • Exceeds CISPR 25 class 5 and CISPR 32B standards for radiated emissions
    The NXF650x family achieves ultra-low radiated emissions through spread-spectrum clocking (SSC) and slew rate control of the output switching voltage. With Nexperia’s proven technology, they meet the CISPR 25 class 5 and CISPR 32B electromagnetic compatibility (EMC) test standards, the strictest automotive and industrial standards for radiated emissions.
  • Fail-safe inputs prevent back-powering and enables any order power up sequence
    The NXF650x series of transformer drivers also have an innovative internal ESD protection scheme that prevents back-powering of the local power supply and reduces design complexity by allowing for implementation of any power-up sequence. These are the only devices in the industry that have this feature.
  • Device-level protection features ensure robust power system delivery
    These devices also have an abundance of device-level protection features like undervoltage protection, soft start to reduce in-rush current, overcurrent protection, Break-Before-Make (BBM) circuitry, and thermal shutdown to ensure robust power system delivery.

The rising need for galvanic isolation

Safety first

As EV adoption surges worldwide and public EV charging stations become ubiquitous, safety becomes paramount. Galvanic isolation in EV charging systems prevents electric shock hazards, shielding both users and vehicles from potential harm.

Grid resilience

With the proliferation of renewable energy sources like solar and wind power, grid integration challenges emerge due to fluctuations in supply. Galvanic isolation helps mitigate these challenges by providing a barrier against electrical disturbances, enhancing grid stability and resilience.

Data integrity

In smart charging systems, where communication between charging stations and central management systems is essential, galvanic isolation safeguards data integrity. It prevents interference from electromagnetic noise and protects sensitive electronic components from damage, ensuring reliable communication and accurate data exchange.

Compatibility

Galvanic isolation facilitates interoperability by bridging compatibility gaps between different electrical systems. This is particularly relevant as EV manufacturers produce vehicles with varying charging requirements, necessitating adaptable charging infrastructure.

Future-proofing infrastructure

As technology advances and new applications emerge, galvanic isolation future-proofs infrastructure investments. Whether it's in EV charging, renewable energy systems, or industrial automation, incorporating galvanic isolation ensures scalability and readiness for evolving needs.