By using photon detection capabilities, devices can perceive things that are usually invisible, achieving breakthrough applications in automotive safety, medical imaging, robotics, and industrial automation. By detecting individual photons, small signals can be detected in real-time, enabling precise distance measurement and early disease detection.
Photomultiplier tube (PMT) was invented in the 1930s and is the gold standard for detecting photons. However, its glass vacuum tube is fragile and too large to be integrated into key applications such as automobiles, drones, handheld devices, or consumer devices. In contrast, solid-state avalanche photodiodes (APDs) are more practical but less sensitive than PMT.
When product designers need a chip level alternative that combines PMT sensitivity and APD practicality, they can try a new generation of photon detection technology - silicon photomultiplier tubes (SiPM). Broadcom's AFBR-S4 SiPM series achieves state-of-the-art photon detection capabilities, and designers can easily integrate it into LiDAR, medical scanners, industrial sensors, or other applications with high demand.
Illuminate the Light of Innovation
Light can transmit important information such as distance, motion, chemistry, and radiation through each photon. The detection of these photons, especially when they are rare or arrive instantaneously, is the basis for realizing technologies such as LiDAR, advanced medical scanners and ultra precision industrial sensors in autonomous vehicle.
The challenge is that photons are extremely small and fleeting, requiring specialized detectors to capture them and amplify them into usable signals. PMT converts individual photons into electrons, which are then amplified by electrodes in a vacuum tube to generate measurable electrical pulses. Although they have high sensitivity and low noise, they are not easy to install in modern compact systems.
APD is a more practical solid-state alternative that amplifies photons through the internal avalanche process in silicon diodes, becoming a smaller and faster solution. However, under low light conditions, these devices find it difficult to reliably detect single photons, resulting in correspondingly weaker signals generated by low light.
SiPM detects single photons like PMT, but its chip structure is compact, low voltage, and durable, allowing even the faintest light to be measured immediately. This device is composed of tiny micro battery arrays, each of which operates in Geiger mode, so one photon can generate a complete and uniform electrical pulse.
The function of each microbattery is essentially like a digital switch that opens at the moment it captures a photon. After triggering, the battery resets and is ready to receive the next photon, so that sensors working together with thousands of batteries can count individual photons and process stronger light signals.
Compact high-performance photon detector
Broadcom's AFBR-S4 SiPM series integrates single photon sensitivity, fast timing, and powerful performance in a compact and practical package, simplifying complexity and easily integrating advanced light detection technology into marketable products.
Broadcom's AFBR-S4E001 evaluation kit (Figure 1) can help product designers quickly bring SiPM based applications to market. This kit provides a ready to use platform for testing, prototyping, and integration of AFBR-S4 sensors, without the need for specialized circuit design. This reduces development risks, as hardware and software can be repeatedly tested before committing to custom PCB layout or production design.