DEMO MANUAL DC1414B-A LTM4601A 5V to 28V , 12A Step-Down IN IN Module Regulator DESCRIPTION Demonstration circuit 1414B-A features the LTM 4601A, rail. Output voltage margining of 5% from the nominal the high efficiency, high density switch mode step-down value is available via the margin control pins MARG0 power module. The input voltage range is 5V to 20V with and MARG1. The LTM4601A data sheet must be read in a jumper selectable output voltage from 0.6V to 5V. The conjunction with this demo manual prior to working on rated load current is 12A, although derating is necessary or modifying demo circuit DC1414B-A. for certain V , V and thermal conditions. The PLLIN IN OUT Design files for this circuit board are available. pin supports synchronizing the Module regulator to All registered trademarks and trademarks are the property of their respective owners. an external clock. The TRACK/SS pin allows the user to program output ramp-up and ramp-down rates which may coincidentally or ratiometrically track with another voltage PERFORMANCE SUMMARY (T = 25C) A PARAMETER CONDITION VALUE Input Voltage Range 5V to 20V Output Voltage V Jumper Selectable (Open for 0.6V) 1.2V, 1.5V, 1.8V, 2.5V, 3.3V, 5V OUT Maximum Continuous Output Current Derating is Necessary for Certain V , V and 12A DC IN OUT Thermal Conditions Default Operating Frequency 850kHz External Synchronous Clock Frequency Range Please Refer to Data Sheet for Minimum t and 600kHz to 1000kHz ON t Requirement. OFF Efficiency V = 12V, V = 3.3V, I = 12A 89.5%, See Figure 2 IN OUT OUT BOARD PHOTO Rev 0 1DEMO MANUAL DC1414B-A QUICK START PROCEDURE Demonstration circuit 1414B-A is easy to set up to evaluate 5. For optional load transient test, apply adjustable pulse the performance of the LTM4601A. Please refer to Figure signal between IOSTEP CLK and GND pins. Pulse am- 1 for proper measurement equipment setup and follow plitude sets the current step. The pulse signal should the procedure below: have very small duty cycle (<15%) to limit the thermal stress on the transient load circuit. The output transient 1. Place jumpers in the following positions for a typical current can be monitored at BNC connector J3 (10mV/A). 1.5V application: OUT 6. For Margining function test, place jumper MARG0 and MARG0 MARG1 RUN V SELECT OUT MARG1 in the configurations shown in the following LO LO ON 1.5V table, measure the output voltage at J4. 2. With power off, connect the input power supply, load MARG1 MARG0 V OUT and meters as shown in Figure 1. Preset the load to 0A LO LO 0 and V supply to be less than 20V. IN LO HI +5% 3. Turn on the power at the input. The output voltage HI LO 5% should be 1.5V 1%. HI HI 0 4. Once the proper output voltage is established, adjust the load within the operating range and observe the output voltage regulation, ripple voltage, efficiency and other parameters. Output ripple should be measured at J4 with a BNC cable. Rev 0 2