DEMO MANUAL DC1866A LTM8052 36V, 5A, 2-Quadrant CVCC Step-Down Module Regulator DESCRIPTION Demonstration circuit 1866 is a 36V, 5A, 2-quadrant CVCC There must be something on the input power bus to ac- step-down Module regulator featuring the LTM 8052. cept or use the energy. The demo circuit is designed for a 2.5V output from an The LTM8052 data sheet gives a complete description of input voltage range of 6V to 36V. The output can source 5A the part, operation and application information. The data- or sink 5A. The circuit can be operated in either constant sheet must be read in conjunction with this demo manual voltage mode or constant current mode. for demo circuit 1866. When the output sinks current, the circuit maintains Design files for this circuit board are available at its output voltage regulation by power conversion, not DEMO MANUAL DC1866A QUICK START PROCEDURE 1. With power off, connect the input power supply to V Demonstration circuit 1866 is an easy way to evaluate IN and GND. the performance of the LTM8052. Refer to Figure 2 for proper measurement equipment setup and follow the 2. Connect a load to V and GND. OUT procedure below: 3. Turn on the power at the input. Note: When measuring the input or output voltage ripple, 4. Check for the proper output voltage and current. care must be taken to avoid a long ground lead on the oscilloscope probe. Measure the input or output voltage Note: If there is no output, temporarily disconnect the ripple by touching the probe tip directly across the V IN load to make sure that the load is not set too high. and GND or V and GND terminals. OUT 5. Once the proper output voltage is established, adjust the load and input within the operating ranges and observe the output voltage regulation, output current regulation, ripple voltage, efficiency and other parameters 0 20 40 60 80 100 120 0 0.5121.5 2.53 3.54 4.5 5 FREQUENCY (MHz) DC1866 F01 Figure 1. DC1866A Output Noise Spectrum (V = 12V, V = 2.5V, I = 5A) IN OUT OUT dc1866afa 2 INTENSITY (dBm)