Passive optical networks (PON) use burst type optical transmitters that transmit data (have optical output power) for a very short period of time. These transmitters are only active (bursting data) a small percentage of the time and the burst time will vary from one burst to another. These factors lead to difficulties in implementing a low-cost burst TX power monitor. This application note illustrates a simple and low-cost method for generating a burst TX power monitor using the MAX3643 laser driver and the DS1863 or DS1865 controllers. Test data is also provided illustrating the operation and performance of the monitor circuit.