The AD737 is a low power, precision, monolithic true rms-to-dc converter. It is laser trimmed to provide a maximum error of 0.2 mV 0.3% of reading with sine-wave inputs. Furthermore, it maintains high accuracy while measuring a wide range of input waveforms, including variable duty cycle pulses and triac (phase) controlled sine waves. The low cost and small physical size of this converter make it suitable for upgrading the performance of non-rms "precision rectifiers" in many applications. Compared to these circuits, the AD737 offers higher accuracy at equal or lower cost.