I have a 60KHz pulse, out of a sensor with amplitude of about 200mv I need, in real time, to generate a 0 -10 V ( or 4-20ma) signal which represents the area of my pulse. This signal will be feeding a data collection system which will be sampling at around 1Hz, so I have lots of time. I would like to have an average over many pulses (several hundred to several thousand). The pulse is pretty stable so it is not really necessary to take that long of an average. Optimally the circuit will be as simple as possible. While maintaining long term stability. References or direct help will be welcome. Off the top of my head I think I need a simple integrator with some form of an amplifier. Is there a cheap solid state alternative? Unnecessary details: I am placing a photo detector behind a mirror in the beam path of a high power laser to measure the transmitted power, the main beam is reflected. This will enable us to monitor the laser power in real time with no interruption to our process.