DC1588A Analog Devices

DEMO MANUAL DC1588A LTM4611EV: Ultralow V 15A Step-Down IN Power Module Regulator DESCRIPTION Demonstration circuit DC1588A features the LTM 4611EV, output voltage sense feature improves the output voltage a low input voltage 15A step-down power module. The accuracy under high loads. These features and the avail- operating input voltage range is 1.5V to 5.5V with an out- ability of the LTM4611EV in a compact 15mm 15mm put voltage range from 0.8V to 5V. DC1588A can support 4.32mm LGA package make the demonstration circuit a load current up to 15A, while derating may be neces- ideal for use in many high density point-of-load regula- sary for different V , V and thermal conditions. The IN OUT tion applications. The LTM4611 data sheet must be read LTM4611EV can operate in pulse-skipping mode or Burst in conjunction with this demo manual for working on or Mode operation for high ef ciency under a light load. The modifying the demo circuit 1588A. DC1588A has a default programmable switching frequency Design les for this circuit board are available at of 500kHz and may be synchronized to an external clock DEMO MANUAL DC1588A QUICK START PROCEDURE Demonstration circuit 1588A is easy to set up to evalu- 5. To perform a load transient test, apply a square-wave ate the performance of the LTM4611EV. Please refer to pulse signal between IOSTEP CLK and GND pins. The Figure1 for proper measurement equipment setup and pulse amplitude (3V ~ 3.5V) sets the amplitude of load follow the procedure below: current step. The pulse signal should have very small duty cycle (<10%) to limit the thermal stress on the 1. Place jumpers in the following positions for a typical transient load circuit. The output transient current can 1.8V application: OUT be monitored at BNC connector J6 (15mV/A). JP4 JP1 JP2 JP3 6. The LTM4611 can be synchronized to an external clock V SELECT RUN MODE/PLLIN TRACK/SS OUT signal. Place the jumper JP2 in the EXTCLK position 1.8V ON FCM SS and apply the clock signal on the CLKIN (TP17) test point. 2. With power off, connect the input power supply, load and meters as shown in Figure 1. Preset the load to 7. The output of LTM4611 can track another supply. The 0A and V supply to be 5V. IN jumper JP3 allows selection of the soft-start or output tracking feature. If tracking external voltage is selected, 3. Turn on the power supply at the input. The output volt- the corresponding test point, TRACK (TP7), needs to age should be 1.8V 1.5%. be connected to a valid reference voltage signal. 4. Once the proper output voltage is established, adjust the load within the operating range and observe the output voltage regulation, output voltage ripple, ef ciency and other parameters. Output ripple should be measured at J5 with a BNC cable. LOAD 0A TO 15A V IN V 1.5V TO 5.5V + V + + A A + DC1588A F01 Figure 1. Test Setup of DC1588A dc1588af 2 +