Enpirion(R) Power Evaluation Board User Guide EN5366QI PowerSoC Enpirion EN5366QI 6A DCDC Converter w/Integrated Inductor Evaluation Board Introduction Thank you for choosing Altera Enpirion power products! You are evaluating a complete power system on silicon: * The EN5366QI features integrated inductor, power MOSFETS, Gate Drive, Compensation Network, and controller and protection circuitry. This level of integration delivers a substantial reduction in footprint and part count over competing solutions. * The EN5366QI features resistor divider output voltage programming. The resistor divider allows the user to set the output voltage to any value within the range 0.8V to (VIN-VDROPOUT ). The evaluation board comes populated with a divider pair that produces 1.5V output. There is also a footprint for a trimpot to allow the user to easily program the output over the full output range if desired, or resistor Ra1 (R6) can be changed to select a different output voltage setting. * The user can also program the Over-Voltage-Protection (OVP) trip level using a separate resistor divider. The board does NOT come with the OVP resistors populated * The input filter capacitor section is populated with 2 x 22uF 10V rated X5R MLC capacitors. The output filter section is populated with 5 x 10uF 6.3V rated X5R MLC capacitors to achieve the required ~50uF of output capacitance. The combination of 5 x 10uF caps yields a very low ESR and hence low output ripple. A single 47uF capacitor can be substituted for the input and output filter sections if a minimum footprint configuration is desired. The Soft-start capacitor is a small 10V rated 15nF X5R MLCC. * Easy jumpers are provided for the following signals: o Enable * Numerous test points are provided as well as banana plugs for input and output connections * The board comes with input decoupling and reverse polarity protection to protect the device from common setup mishaps. Page 1 of 5 www.altera.com/enpirion Enpirion(R) Power Evaluation Board User Guide EN5366QI PowerSoC Quick Start Guide Figure 1 shows a top view of the evaluation board. WARNING: complete steps 1 through 4 before applying power to the EN5366QI evaluation board. STEP 1: Set the "ENABLE" jumper to the Disable Position. STEP 2: Connect Power Supply to the input power connectors, VIN (+) and GND (-) as indicated in Figure 1. CAUTION: be mindful of the polarity. Even though the evaluation board comes with reverse polarity protection diodes, it is rarely a good idea to reverse the input polarity. STEP 3: Connect the load to the output connectors VOUT (+) and GND (-), as indicated in Figure 1. STEP 4: Apply VIN to the board and move the ENABLE jumper to the enabled position. The EN5366QI is now powered up! NOTE: There is no de-bouncing circuitry associate with the enable pin. NOTE: The resistor divider is set to produce a 1.5V output. Details on changing the divider is provided in a later section. Page 2 of 5 www.altera.com/enpirion Enpirion(R) Power Evaluation Board User Guide EN5366QI PowerSoC Figure 1. Evaluation Board Layout. Output Voltage Select Programming Output Voltage and OVP The EN5366QI output voltage is programmed using a simple resistor divider network. Figure 2 shows a schematic view of the resistor divider configuration. The evaluation board come pre-populated with Ra1 = 2k. (R6 on the evaluation board silk screen) and Ra2 = 2k (R3 on the evaluation board silk screen), to provide an output voltage of 1.5V. The EN5366QI output voltage and over voltage thresholds are determined by the voltages presented at the XFB and XOV pins respectively. These voltages are set by way of resistor dividers between VOUT and AGND with the midpoint going to XFB and XOV. Page 3 of 5 www.altera.com/enpirion Enpirion(R) Power Evaluation Board User Guide EN5366QI PowerSoC It is recommended that Rb1 and Rb2 resistor values be ~2k. Use the following equation to set the resistor Ra1 (R6 on the evaluation board silk screen) to change the output voltage from the pre-populated value for VOUT = 1.5V: Ra1 = (Vout - 0.75V ) * Rb1 0.75V If over-voltage protection is desired, use the following equation to set the resistor Ra2 for the desired OVP trip-point. Note that the evaluation board leaves these resistors un-populated. Ra 2 = (OVPtrip - 0.90V ) * Rb2 0.90V By design, if both resistor dividers are the same, the OV trip-point will be 20% above the nominal output voltage. VIN PVIN 47F POK VOUT VOUT AVIN Ra2 Ra1 XOV SS CSS ~50uF XFB AGND PGND Rb2 Rb1 Figure 2. VOUT and OVP resistor divider networks. NOTE: if no OVP divider is present, there will be no over-voltage protection and POK will remain "high" as long as VOUT remains above 90% of the nominal V OUT setting. Test Recommendations Recommendations To guarantee measurement accuracy, the following precautions should be observed: 1. Make all input and output voltage measurements at the board using the test points provided. This will eliminate voltage drop across the line and load cables that can produce false readings. 2. Measure input and output current with series ammeters or accurate shunt resistors. This is especially important when measuring efficiency. 3. Use a balanced impedance probe tip to measure switching signals to avoid noise coupling into the probe ground lead. Page 4 of 5 www.altera.com/enpirion Enpirion(R) Power Evaluation Board User Guide EN5366QI PowerSoC Input and Output Capacitors The input capacitance requirement is approximately 50uF for the EN5366QI. The EN5366QI evaluation board comes populated with 2 x 22uF 10V 1210 X5R capacitors. To achieve a minimum footprint configuration the input capacitors can be replaced with a single 47uF MLC capacitor. Altera recommends that low ESR MLC capacitors be used. The voltage rating should rated high enough to provide adequate margin for your application. The output capacitance requirement is approximately 50uF of capacitance. The EN5366QI-E evaluation board comes populated with 5 x 10uF 6.3V 1206 MLC capacitors. The 5 parallel capacitors provide for reduced ESR and hence lower output ripple voltage. If a minimum footprint configuration is desired, the 5 x10uF capacitors can be replaced with a single 47uF MLC capacitor. NOTE: Capacitors must be X5R or X7R dielectric formulations. NOTE: Please refer to product datasheet for specific recommendations. Contact Information Altera Corporation 101 Innovation Drive San Jose, CA 95134 Phone: 408-544-7000 http://www.altera.com/ (c) 2013 Altera Corporation--Confidential. All rights reserved. ALTERA, ARRIA, CYCLONE, ENPIRION, HARDCOPY, MAX, MEGACORE, NIOS, QUARTUS and STRATIX words and logos are trademarks of Altera Corporation and registered in the U.S. Patent and Trademark Office and in other countries. All other words and logos identified as trademarks or service marks are the property of their respective holders as described at www.altera.com/common/legal.html. Altera warrants performance of its semiconductor products to current specifications in accordance with Altera's standard warranty, but reserves the right to make changes to any products and services at any time without notice. Altera assumes no responsibility or liability arising out of the application or use of any information, product, or service described herein except as expressly agreed to in writing by Altera. Altera customers are advised to obtain the latest version of device specifications before relying on any published information and before placing orders for products or services. Page 5 of 5 www.altera.com/enpirion