A CMOS Bidirectional -69 mA to +63 mA Output Range Voltage Controlled Current Source for Laser Diode Current Control in FTTx Applications

摘要

This paper presents a CMOS bidirectional voltage controlled current source (BVCCS) for use as an adjustable current source for laser diodes and photo diodes in optical transceiver modules in FTTx applications. The BVCCS is implemented based on the modified Howland current pump topology and utilizes CMOS complementary folded cascode (CFC) amplifiers with very large input voltage swing. The BVCCS has an output current range from -69 mA to +63 mA and consumes a maximum power of 325.11 mW from a 3.3 V supply when operating in the current sinking mode.