ROHM Schottky Diode Improves Protection for Image Sensors in Harsh Conditions

As advanced driver assistance systems rely on higher pixel count cameras, the power architecture around image sensors is becoming more sensitive. When a sensor is exposed to light while powered down, a photovoltaic voltage can be generated inside the pixel structure. If this voltage is left unmanaged, it can damage the sensor or surrounding electronics.

Traditionally, a Schottky barrier diode is used to clamp the voltage and prevent backflow into sensitive circuitry. The issue is that diodes made for low conduction loss tend to leak more current at high temperatures. This leakage can heat surrounding devices and cause malfunctions during normal operation.

A Diode Designed for Active and Standby Protection

ROHM has introduced the RBE01VYM6AFH Schottky diode to address these competing requirements. The design focuses on combining a low forward voltage with low reverse leakage so the same device can protect image sensors whether systems are actively powered or turned off.

In automotive image modules, where light exposure can be intense even during vehicle shutdown, this dual behaviour is particularly important. A single component that handles both situations simplifies the protection network and reduces the footprint.

Key Characteristics for Camera Module Design

The diode maintains a forward voltage of less than 300 mV at 7.5 mA even at very low ambient temperatures. At the same time, reverse leakage is kept below 20 microamperes at a 3 V rating at 125 degrees Celsius. This balance reduces the risk of thermal runaway that can occur when leakage rises sharply under heat.

The package is a flat lead SOD 323HE measuring 2.5 by 1.4 millimetres. Its small outline supports tight lens and sensor assemblies where there is little space for power protection components. The part is qualified to AEC Q101, making it suitable for automotive reliability standards.

Integration Into Next Generation Imaging Systems

Engineers working with both interior and exterior camera systems can place the protection diode close to the sensor to clamp unwanted photovoltaic voltage. The low leakage also helps keep standby power under control, which is a growing requirement in vehicles that must maintain camera readiness.

The RBE01VYM6AFH supports applications such as ADAS cameras, industrial inspection cameras and compact security modules where heat, vibration and bright lighting are common.

Learn more and read the original announcement on www.rohm.com