DEMO MANUAL DC1083A-A LTM4603 Synchronizable 20V, 6A Step-Down Module Regulator DESCRIPTION Demonstration circuit DC1083A-A features the LTM 4603, ramp-up and ramp-down may be programmed through the high efficiency, high density step-down Module the TRACK/SS pin. Margining function is provided for the regulator. The input voltage range is from 4.5V to 20V. The user who wants to stress their system by varying supply output voltage is jumper programmable from 0.6V to 5V. voltages during testing. The LTM4603 data sheet must be The rated load current is 6A, while derating is necessary read in conjunction with this demo manual prior to working for certain V , V , and thermal conditions. Applying an on or modifying demo circuit DC1083A-A. IN OUT external clock signal to the PLLIN pin forces the Module Design files for this circuit board are available at regulator to operate at the same frequency. The output DEMO MANUAL DC1083A-A QUICK START PROCEDURE Demonstration circuit DC1083A-A is an easy way to evalu- 5. To measure input and output ripple, please refer to ate the performance of the LTM4603EV. Please refer to Figure 2 for proper setup. Figure 1 for proper measurement equipment setup and 6. For optional load transient test, apply adjustable pulse follow the procedure below: signal between IOSTEP CLK and GND pins. Pulse ampli- 1. Place jumpers in the following positions for a typical tude sets the current step. The pulse signal should have 1.5V application: very small duty cycle (<15%) to limit the thermal stress OUT on the transient load circuit. The output transient current MARG0 MARG1 RUN VOUT SELECT can be monitored at BNC connector J3 (10mV/A), the LO LO ON 1.5V output voltage can be monitored at BNC connector J4. 7. For margining function test, place jumper MARG0 and 2. With power off, preset the load to 0A and V supply to IN MARG1 in the configurations shown in the following be less than 20V. Connect the input power supply, load table, measure the output voltage at J4. and meters as shown in Figure 1. MARG1 MARG0 VOUT 3. Turn on the power at the input. The output voltage LO LO 0 should be 1.5V 2%. LO HI +5% 4. Once the proper output voltage is established, adjust the HI LO 5% load within the operating range and observe the output HI HI 0 voltage regulation, ripple voltage, efficiency and other parameters. DC1083AA F01 Figure 1. Test Setup of DC1083A-A (DRV Bias Supply is Optional) CC dc1083aaf 2