Cable Drop Compensation without Sense Wires
Linear Technology announces the LT6110 cable drop compensator, a new device that improves voltage regulation at remote loads without the need for Kelvin sense wires. The new device has been architected for use with most types of voltage regulators and can provide several volts of load regulation compensation. It will compensate for the voltage drop due to resistance in a wire, circuit board trace or cable and can improve regulation at the load by a factor of 10. It operates with supply voltages that range from 2 V to 50 V.
The LT6110 operates by measuring the load current with a sense resistor and injecting current into the existing regulator’s feedback loop to raise the output voltage. It is designed to work with standard feedback circuits, as well as new “current source” reference devices such as the LT3080. For load currents less than 3 A, the internal 20 milliohm sense resistor simplifies the design. Wide bandwidth achieves fast transient compensation of load steps, and in most cases the savings in wire and labor are more than the cost of the new device.