DEMO MANUAL DC2268A-B LTM4620A Dual 13A or Single 26A Module Regulator Description Demonstration circuit 2268A-B is a high efficiency, high the TRACK/SS pin. Remote output voltage sensing is density, dual 13A, switch mode step-down power supply available for improved output voltage regulation at the load on a compact 1.5 1.2 PCB. It features the LTM4620A point. An optional input inductor L1 reduces the EMI noise Module regulator. The input voltage is from 5.5V to for noise sensitive applications. DC2268A can be easily 16V. The output voltage is programmable from 0.6V to inserted to an edge connector for testing and debugging. 5V. DC2268A-B can deliver up to 13A maximum in each These features and the availability of the LTM4620A in a channel. As explained in the data sheet, output current compact 16mm 16mm 5.01mm BGA package make derating is necessary for certain V , V , and thermal it ideal for use in many high-density point-of-load regula- IN OUT conditions. The board operates in continuous conduction tion applications. The LTM4620A data sheet must be read mode in heavy load conditions. For high efficiency at low in conjunction with this demo manual for working on or load currents, the resistor jumper (R1/R2) selects pulse- modifying the demo circuit DC2268A-B. skipping mode for noise sensitive applications or Burst Design files for this circuit board are available at Mode in less noise sensitive applications. Two outputs can DEMO MANUAL DC2268A-B p s Specifications are at T = 25C A PARAMETER CONDITIONS VALUE Input Voltage Range 5.5V ~ 16V Output Voltage V V = 4.5V ~ 15V, I = 0A ~ 13A 3.3V 1.5% OUT1 IN OUT1 Output Voltage V V = 4.5V ~ 15V, I = 0A ~ 13A 1.5V 1.5% OUT2 IN OUT2 Per-Channel Maximum Continuous Output Current Derating Is Necessary for Certain V , V and Thermal 13A IN OUT Conditions. Default Operating Frequency 750kHz Resistor Programmable Frequency Range 250kHz to 780kHz External Clock Sync. Frequency Range 400kHz to 780kHz Efficiency of Channel 1 V = 12V, V = 3.3V, I = 13A, f = 750kHz 91.8% See Figure 3 IN OUT2 OUT2 SW Efficiency of Channel 2 V = 12V, V = 5V, I = 13A, f = 750kHz 93.9% See Figure 4 IN OUT1 OUT1 SW Load Transient of Channel 1 V = 12V, V = 3.3V, I = 6.5A ~ 13A See Figure 5 IN OUT2 STEP Load Transient of Channel 2 V = 12V, V = 5V, I = 6.5A ~ 13A See Figure 6 IN OUT1 STEP Quick s p D Demonstration circuit DC2268A-B is easy to set up to 4. Once the proper output voltage is established, adjust the evaluate the performance of the LTM4620A. It can be load within the operating range and observe the output easily inserted to an edge connector (SAMTEC MEC2- voltage regulation, output voltage ripple, efficiency and 20-01-L-DV--TR) for testing and debugging. Please refer other parameters. Output ripple should be measured to Figure 2 for proper measurement setup and follow the at Co3 and Co4. procedure below: 5. (Optional) LTM4620A can be synchronized to an exter- 1. Pull up the RUN1 (J1 pin 22) and RUN2 (J1 pin 24) nal clock signal. Remove R2 and apply a clock signal between 1.4V to 5V or leave them floating. (0~5V, square wave) to MODE-PLLIN pin. 2. With power off, connect the input power supply, load 6. (Optional) LTM4620A can be configured for a 2-phase and meters as shown in Figure 1. Preset the load to 0A single output at up to 36A on DC2268A-B. Install 0 and V supply to 12V. resistors on R26, R27, R28, R29, R32, and remove IN R14, R18, R30. Output voltage is set by R7 based on 3. Turn on the power supply at the input. The output volt- equation V = 0.6V(1 + 60.4k/R7). OUT age in channel 1 should be 3.3V 1.5% (3.2505V ~ 3.3495V) and the output voltage in channel 2 should be 5V 1.5% (4.925V ~ 5.075V), dc2268abfa 2 ure roce tart ummary erformance