DEMO MANUAL DC1870A LT3081 1.5A Single Resistor Rugged Linear Regulator with Monitors Description DC1870A is a 1.5A low dropout linear regulator featuring The LT3081 is offered in the packages of 16-lead TSSOP, LT 3081. The device is designed for rugged industrial ap- 7-lead TO-220, 7-lead DD-Pak, and a 12-lead 4mm plications and can be paralleled for higher output current 4mm DFN. or heat spreading. Besides paralleling, the LT3081 also The LT3081 data sheet gives a complete description of presents other features including adjustability to zero V , OUT the device, operation and application information. The data reverse protection for input and output-to-input voltages, sheet should be read in conjunction with this quick start temperature monitor, output current monitor, etc. guide for working on or modifying the DC1870A. A key feature of the LT3081 is the extended safe operating Design files for this circuit board are available at area (SOA). With the precision zero TC 50A reference DEMO MANUAL DC1870A Quick s p D DC1870A is easy to set up to evaluate the performance 3. Turn on the power at the V . IN of the LT3081. Refer to Figure 1 for proper measurement NOTE: Make sure that the V voltage does not exceed IN equipment setup and follow the procedure below: 36V. NOTE: When measuring the input or output voltage ripple, 4. Check for the proper output voltages: care must be taken to avoid a long ground lead on the NOTE: If there is no output, temporarily disconnect the oscilloscope probe. Measure the input or output voltage load to make sure that the load is not set too high or ripple by touching the probe tip directly across the terminals is shorted. of the input or output capacitors. See Figure 2 for proper scope probe technique. 5. Once the proper output voltages are established, adjust the loads within the operating range and observe the 1. Use JP1 to set the desired output voltage. output voltage regulation, efficiency and other param- 2. With power off, connect the input power supply to V IN eters. and GND. NOTE: Make sure that the power dissipation is limited below the thermal limit. Figure 1. DC1870A Proper Equipment Setup DC1870A F02 V OR V GND IN OUT Figure 2. Measuring Input or Output Ripple dc1870af 2 ure roce tart