01/06/2026
Photovoltaic Optocoupler for Isolated Solid-State Relays:
THE CHD320 WITH HIGHER GATE VOLTAGE FOR SPACE SATELLITE APPLICATIONS
ISOCOM Limited has introduced an innovative photovoltaic optocoupler specifically designed for isolated Solid-State Relays. This advanced component boasts a minimum open voltage (V ) of 10V, which is double that of standard 5-volt devices. As a result, only a single device is required to effectively drive the gate of a high-voltage power MOSFET.
“The photocoupler is housed in a ceramic package featuring either metal hermetic lid sealing or ceramic hermetic lid sealing, measuring a compact 3.85 x 3.85 x 1.6 mm. This design makes it ideal for driving the gates of high-voltage power MOSFETs, which are essential for developing a galvanically isolated solid-state relay (SSR) function, ” says Thomas Bayat, Managing Director and CEO of Isocom.
To implement and configure an isolated Solid State Relay (SSR) for switching high voltages and large currents, designers usually pair a photovoltaic coupler with a MOSFET.
Typical SSRs integrate these components as the output device and are generally well-suited for applications that require on/off control of electrical currents in aerospace equipment. Typical application use is the I/O relay output for, inrush current protection in PSUs, battery voltage monitoring in battery monitoring systems and ground fault detection. Additionally, they can be used to control power and signal lines in instrumentation applications.
The CHD320 includes the optical components; however, it does not feature the MOSFET. The minimum open voltage (V ) of 10V, which is double that of a single device, is essential for driving the gate of a high-voltage power MOSFET. This configuration leads to a reduction in part count, enhances reliability, and contributes to savings in PCB space and bill of materials (BoM) costs.
The CHD320 is ISOCOM's first photovoltaic coupler, boasting a minimum isolation voltage (BVS) of 500V rms. Produced in AS9100D certified facilities, this photocoupler is suitable for use in Defence, Aerospace, and Space applications that operate on high voltage DC or AC systems. The photocoupler operates effectively within a high-temperature range of -55 to 125°C.
For further information please contact us at: sales@isocom.uk.com