HFBR-1521Z

The Broadcom HFBR-1521Z is a fiber optic transmitter designed for low-cost, short-distance fiber optic data links using plastic optical fiber (POF) or hard clad silica (HCS) fiber. The 660nm visible red LED provides easy visual alignment during installation and troubleshooting. The VersaLink connector system ensures reliable, snap-in connection with the companion HFBR-2521Z receiver. Operating at data rates from DC to 5MBaud, the transmitter-receiver pair achieves link distances up to 50 meters with 1mm POF. The fiber optic link provides complete electrical isolation and immunity to EMI/RFI, making it ideal for noisy industrial environments where copper cables would be problematic.

The HFBR-1521Z operates as a fiber optic LED transmitter: 1) Electrical-to-Optical Conversion: The input digital signal drives the internal 660nm LED through a current-limiting circuit. When the input is high, the LED emits light at 660nm (visible red). When low, the LED is off. The 60mA typical forward current produces -13dBm optical output power into 1mm POF. 2) Optical Coupling: The LED output is mechanically coupled to the VersaLink connector, which aligns the fiber core precisely with the LED emission area. The 660nm wavelength matches the peak sensitivity of silicon photodetectors used in the companion receiver. 3) Fiber Transmission: The modulated light travels through the plastic optical fiber via total internal reflection. The 1mm core diameter of POF provides easy alignment and high coupling efficiency. At the receiver end (HFBR-2521Z), a photodiode converts the optical signal back to electrical form.

• Isolated serial data link between high-voltage power electronics and control system
• Industrial PLC communication in EMI-heavy environments
• Medical equipment data transmission with patient isolation