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 thick film type low resistance resistors UR73, SR73 offer wide resistance and T.C.R. variation from 10mΩ to 10Ω and T.C.R. of ±100 x10-6/K.
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 plate chip type low resistance resistor TLR series has extremely small parasitic inductance and enables high precision current detection.