Virtual remote sense controller eliminates remote sense wires

According to Linear, the LT4180, eliminates the remote sense wires required to compensate for the voltage drop in cables, wires and circuit board trace runs. Voltage drops in wiring and cables that cause load regulation errors are usually corrected by an additional set of sensing wires. The LT4180 is designed to continuously interrogate the line impedance and correct the regulator's output voltage. The device is said to maintain a corrected regulated voltage at the load, regardless of current or line impedance. The 3 to 50V input voltage range addresses applications such as remote instrumentation, battery charging, notebook power, surveillance equipment and halogen lighting. Its output correction is obtained by modulating the output and measuring the incremental change in voltage that occurs with a change in current. Any modulation noise is eliminated by the supply bypass capacitor located at the load. Robert Dobkin, vice president of engineering and cto for Linear Technology, said: "The LT4180 provides a new function for power supply designers. Excellent regulation is obtained without sense wires, eliminating the need for point-of-load regulators. Difficult regulation problems such as long wire runs or system retrofits can be accommodated. With halogen lights, the light output drops more quickly than power, so keeping the correct voltage more than compensates for any additional cost of the power supply." Three temperature grades are available: an extended grade version from -40 to 85^°C, an industrial grade version from -40 to 125^°C and a military grade option from -55 to 125^°C.