PDB120C In Stock

The PDB120C by ThorLabs is an advanced InGaAs balanced amplified photodetector engineered to deliver high-performance measurements in various optical applications. With two photodiodes and a state-of-the-art high-speed transimpedance amplifier, this device is designed to provide superior noise reduction due to an efficient common mode rejection. The transimpedance amplifier creates an output voltage according to the differences between the photocurrents in two photodiodes, also referred to as the dual optical input signals.

The PDB120C features a transimpedance gain of 180x103 V/A for high impedance loads and 90x103 V/A into 50 Ω load, ensuring accurate and precise measurements across a broad wavelength range of 800 nm to 1700 nm. With a minimum noise equivalent power of 3.3 pW/√Hz from DC-10 MHz and an approximate minimum integrated noise of 53 nWRMS, the PDB120C is a highly responsive photodetector that delivers reliable results. It features PIN InGaAs photodiodes with a detector diameter of 0.3 mm, and offers a bandwidth of DC to 75 MHz.

The PDB120C has two modes of operation: balanced mode and single detector mode. In single detector mode, the optical input power should be below the CW saturation power listed in specification to avoid the saturation of the RF Output amplifier. In balanced mode, the difference between the optical input powers should be less than the CW Saturation Power. The photodetector's external neutral density filters or attenuators can be used to reduce the input light level, if necessary.

The PDB120C is designed for ease of use and installation. It is housed in a shielded, rugged, aluminum enclosure with a #8-32 and M4 x 0.7 threaded mounting adapter plate that can be positioned by the user so it is located at either the back or the bottom of the detector. The adapter plate can be positioned at the bottom, allowing the unit to be mounted to a post using screws and an Allen wrench. The photodetector has two optical inputs with removable and interchangeable FC connectors for easy adaptation to either fiber-coupled or free-space applications. Additionally, three electrical SMA connectors provide a balanced output signal and a power monitor for each of the two input signals.