To achieve power management performance of portal devices, high precision measurement of current is required. To measure the circuit current in general, first you insert current sense resistors in serial into a circuit then measure each voltage of both ends of the resistor. Like smartphones, however, when the current gap happens to be more than a hundred times between standby and operating APs, the current in both cases should be measured precisely and the current sense resistors required to be high precision of low T.C.R. , less affected by temperature change. Our metal film type low resistance resistors MPR series offer wide resistance and T.C.R. varied from 0.25mΩ to 120 mΩand T.C.R. of ±50 x10-6/K.
Smartphones and wearable devices apply numbers of 01005-inch size electronic components. The requirements for higher performance in the restricted space are increasing, as requirements for composition of components are becoming remarkable than downsizing of chip product. In mounting technology, narrow space mounting is achieved by fillet-less mounting to improve mounting density. Not only a resistor but resistor network will need downsizing and area array mounting.
CPU power supplies of notebook PC apply DC-DC converters, which require output stability enabled to follow the load change of CPU, so the switching speed becomes extremely high. Parastic inductance of electronic components applied for control circuit of DC-DC converters will affect largely. So current sense resistors of low parastic inductance are required. Our metal strip resistor MMS Series, MMS5930, MMS8420 for instance, has extremely small parasitic inductance and enables high precision current detection.
Car electronics devices require high reliability as they are under severe environment. Especially for engine peripherals, such devices have to work for long time under high temperature, humidity, tough vibration, dust and other chemical substances. Resistors applied for those applications should have excellent heat resistance, moisture resistance and sulfuration resistance, as well as the high reliability of junction to the PWB to tolerate continuous thermal stress and strong vibration.
LCD projectors or duplicators, their power supplies use high voltage, which require electronic components in the drive circuits to have high max. working voltage. Power supply circuits of EV and HEV use high voltage, which also requires resistors to have high max. working voltage.
Electronic circuit substrate had been applying Pb-contained solder, alloy of tin and lead, but because of lead's adverse effect on human body and environment, the trend of Pb-free solder is becoming popular in recent years. As of July 2006, RoHS regulations in Europe prohibits to use six hazardous materials including lead. Even in other countries like Japan and China, such regulations are becoming enhanced while we are trying hard to eliminate environmental hazardous materials as well as to promote Pb-free terminal resistors in wide lineup.
