DEMO MANUAL DC2147A LTM4631 Ultrathin Dual 10A or Single 20A DC/DC Module Regulator Description Demonstration circuit 2147A features the LTM 4631, ramps up and down through the TRACK/SS pin. The output the high efficiency, high density, dual 10A, switch mode can be set up to either coincidentally or ratio-metrically step-down Module power module regulator. The input track with another supplys output. Remote output voltage voltage is from 4.5V to 15V. The output voltage is pro- sensing is available for improved output voltage regula- grammable from 0.6V to 1.8V. DC2147A can deliver up to tion at the load point. These features and the availability 10A maximum in each channel. As explained in the data of the LTM4631 in a compact 16mm 16mm 1.91mm sheet, output current derating is necessary for certain LGA package make it ideal for use in many high density V , V , and thermal conditions. The board operates in point-of-load regulation applications. The LTM4631 data IN OUT continuous conduction mode in heavy load conditions. sheet must be read in conjunction with this demo manual For high efficiency at low load currents, the MODE jumper for working on or modifying the demo circuit DC2147A. (JP1) selects pulse-skipping mode for noise sensitive ap- Design files for this circuit board are available at plications or Burst Mode operation in less noise sensitive DEMO MANUAL DC2147A p erformance s Specifications are at T = 25C A PARAMETER CONDITIONS/NOTES VALUE Input Voltage Range 4.5V ~ 15V Output Voltage V V = 4.5V ~ 15V, I = 0A ~ 10A, JP1: CCM 1.2V 1.5% (1.182V ~ 1.218V) OUT1 IN OUT1 Output Voltage V V = 4.5V ~ 15V, I = 0A ~ 10A, JP1: CCM 1V 1.5% (0.985V ~ 1.015V) OUT2 IN OUT2 Per-Channel Maximum Continuous Output Derating Is Necessary for Certain V , V and Thermal 10A IN OUT Current Conditions, See Data Sheet for Detail. Default Operating Frequency 650kHz Resistor Programmable Frequency Range 250kHz to 780kHz External Clock Sync Frequency Range 400kHz to 780kHz Efficiency of Channel 1 V = 12V, V = 1.2V, I = 10A, f = 650kHz 81.5% See Figure 2 IN OUT1 OUT1 SW Efficiency of Channel 2 V = 12V, V = 1V, I = 10A, f = 650kHz 78.7% See Figure 3 IN OUT2 OUT2 SW Load Transient of Channel 1 V = 12V, V = 1.2V, I = 5A ~ 10A See Figure 4 IN OUT1 STEP Load Transient of Channel 2 V = 12V, V = 1V, I = 5A ~ 10A See Figure 5 IN OUT2 STEP Quick s tart p D Demonstration circuit 2147A is easy to set up to evalu- 3. Turn on the power supply at the input. The output ate the performance of the LTM4631EV. Please refer to voltage in channel 1 should be 1.2V 1.5% (1.182V Figure 1 for proper measurement setup and follow the ~ 1.218V) and the output voltage in channel 2 should procedure below: be 1V 1.5% (0.985V ~ 1.015V). 1. Place jumpers in the following positions for a typi- 4. Once the proper output voltage is established, adjust cal application: the load within the operating range and observe the output voltage regulation, output voltage ripple, ef- JP1 JP2 JP3 JP4 JP5 JP6 ficiency and other parameters. Output ripple should MODE RUN1 RUN2 TRACK1 TRACK2 CLKOUT SELECT SELECT PHASE be measured at J1 and J2 with BNC cables. 50 CCM ON ON SOFT- SOFT- 90 termination should be set on the oscilloscope or START START BNC cables. 2. With power off, connect the input power supply, load and meters as shown in Figure 1. Preset the load to 0A and V supply to 12V. IN dc2147af 2 ure roce ummary