Comprised of a photo MOSFET optically coupled with an infrared LED, Toshiba Electronics Europe has introduced four ultra-small photorelays. The TLP3475 and TLP3440 have been designed to deal with high frequency signals; while the TLP3417 and TLP3420 are suitable for dealing with the high voltages required for signals of measured devices such as semiconductor testers.
An alternative to mechanical relays, photorelays provide design engineers with fast switching speed, high reliability, lower power consumption and noise-free operation. The devices are designed for applications where the mounting areas on boards need to be drastically reduced and high speed / high voltage signals need to be measured, such as semiconductor testers, measurement equipment, medical devices and probe cards.
As the cabinets of various types of semiconductor testers and measurement equipment are becoming smaller, demand for ultra-small photorelays has increased. The TLP3475, TLP3440, TLP3417 and TLP3420 are supplied in ultra-small VSON4 packages, which enable high-density assembly and, compared to USOP4 packages, can shrink the assembly area by 50% and the assembly volume by 60%.
The TLP3475 features typical ON-state resistance of 1Ω, output capacitance of 12pF, maximum OFF-state terminal voltage of 50V and maximum ON-state current of 0.3A. This enables improved pass characteristics at the time of relay contact-on and avoids problems during high frequency signal transmission.
The TLP3440 provides maximum OFF-state output terminal voltage of 40V, maximum ON-state current of 0.12A, typical ON-state resistance of 12Ω and output capacitance of 0.45pF, improving leakage characteristics for high frequency signals in the off state.
TLP3417 and TLP3420 feature maximum ON-state current of 0.12 and 0.1A, typical ON-state resistance of 7 and 8Ω and typical output capacitance of 5 and 6pF, respectively. They can withstand 80 and 100V, respectively, to enable the high voltage measurements needed for testing SoC devices.
All four devices achieve maximum trigger LED currents of 3mA and minimum isolation voltages of 300Vrms.