DC1856B-B Analog Devices

DEMO MANUAL DC1856B-B LTM4649EY High Efficiency 10A Step-Down Module Regulator Description Demonstration circuit 1856B-B features the LTM 4649EY Output voltage tracking is available through the TRACK/SS Module regulator, a high performance high efficiency pin for supply rail sequencing. External clock synchroniza- step-down regulator. The LTM4649EY has an operating tion is also available through the CLKIN pin. The LTM4649 input voltage range of 4.5V to 16V and is able to provide data sheet must be read in conjunction with this demo an output current of up to 10A. The output voltage is pro- manual for working on or modifying demo circuit 1856B-B. grammable from 0.6V to 3.3V and can be remotely sensed Design files for this circuit board are available at with the internal differential remote sensing amplifier. The DEMO MANUAL DC1856B-B Quick s tart p D Demonstration circuit 1856B-B is an easy way to evaluate 5. Once the proper output voltage is established, adjust the performance of the LTM4649EY. Please refer to Figure 1 the load current within the 0A to 10A range and observe for test setup connections and follow the procedure below. the load regulation, efficiency, and other parameters. Output voltage ripple should be measured at J6 with a 1. With power off, place the jumpers in the following posi- BNC cable and oscilloscope. tions for a typical 1.8V application: OUT 6. To observe increased light load efficiency place the JP8 JP7 JP9 JP2 mode pin jumper (JP9) in the Burst Mode operation TRACK/SS RUN MODE V Select OUT position. To observe increased light load efficiency with SS ON CCM 1.8V a reduced output ripple as compared to Burst Mode operation, place the mode pin jumper in the pulse- 2. Before connecting input supply, load and meters, preset skipping position. the input voltage supply to be between 4.5V to 16V. 7. For optional load transient testing apply an adjustable Preset the load current to 0A. positive pulse signal between IOSTEP CLK and GND 3. With power off, connect the load, input voltage supply pins. The pulse amplitude sets the load step current and meters as shown in Figure 1. amplitude. The pulse width should be short (< 1ms) and pulse duty cycle should be low (< 15%) to limit the 4. Turn on input power supply. The output voltage meter thermal stress on the load transient circuit. The load should display the selected output voltage 2%. step current can be monitored with a BNC connected to J5 (10mV/A). dc1856bbf 2 ure roce