February 2010 Enpirion EP5348UI 400mA Synchronous DC/DC Converter Module Evaluation Board Introduction You are evaluating a new class of DCDC converter product, a complete power system on silicon. This user guide is applicable to evaluation boards with serial numbers from E00007273 to E00007307. In addition to this document, you will also need the latest device datasheet. * * * * * * The EP5348UI is a complete module with integrated magnetics. The evaluation board is designed to offer a wide range of engineering evaluation capabilities. Output voltage is programmed using a resistor divider. The board comes populated with four pre-placed resistors and a jumper to choose one offour preset output voltages. Easy jumpers are provided for the following signals: o Enable o VOUT selection Numerous test points are provided as well as clip leads for input and output connections The board comes with input decoupling and input reverse polarity protection to protect the device from common setup mishaps. Quick Start Guide Figure 1 shows a top view of the evaluation board. STEP 1: Set the "ENABLE" jumper J1 to the Disable Position, as shown here. STEP 2: Set the output voltage by setting jumper J4 to one of the pre selected output voltage settings. See the Output Voltage Select section. STEP 3: Connect Power Supply to the input clip leads, VIN (+) and GND (-). CAUTION: Even though the evaluation board comes with reverse polarity protection diodes, be mindful of the polarity. STEP 4: Connect the load to the output clip leads VOUT (+) and GND (-). Page 1 of 6 (c)Enpirion 2008 all rights reserved, E&OE Enpirion Confidential February 2010 STEP 5: Power up the board and move the ENABLE jumper to the enabled position. The EP5348UI is now powered up. Please note jumper J5 LLM is not to be used with this part. Please leave the jumper in the disabled position. Figure 1. Evaluation Board Layout. Page 2 of 6 (c)Enpirion 2008 all rights reserved, E&OE Enpirion Confidential February 2010 Output Voltage Select The output voltage of the EP5348UI is programmed using a simple resistor divider. The evaluation board comes pre-populated with a set of four jumpers that allow the user to choose one of four preset voltages. Refer to Figure 2 for the specific settings. If no jumper is populated the default voltage setting will be 0.6V. Higher output voltages can be programmed by populating multiple J4 jumper positions. It is also possible to remove one of the preset resistors and replace with another value to generate any desired output within the devices operating range. Refer to the product data sheet for further information on setting the output voltage. CAUTION: None of the J4 jumpers can be changed while the device is enabled. Doing so could damage the part. Figure 2. Close up of the VOUT setting jumpers, J4.The output voltage settings, from left to right are: 1.0V, 1.59V, 1.80V, and 2.41V. Jumper as shown here selects 1.0V. Figure 4 shows the resistors that make up the voltages mentioned above. Multiple jumpers can be populated to achieve other output voltages. Any of the resistors R2, R3, R5, or R6 can also be changed to modify the corresponding VOUT setting. Do not change R1. This value has been selected as part of the control loop compensation circuit. Page 3 of 6 (c)Enpirion 2008 all rights reserved, E&OE Enpirion Confidential February 2010 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 low loop inductance scope probe across COUT to measure VOUT Ripple to avoid noise coupling into the probe ground lead. The recommended probe configuration is shown in Figure 3. Figure 3. Recommended probe configuration. 4. The board has soldermask openings for 0805 ceramic capacitors at the input and output edges. If you are planning to do any radiated EMI testing on this board, place a 10uF, 0805, X7R or X5R capacitor at each board edge. The added capacitor at the input edge is for highfrequency decoupling of the input cables. The added capacitor at the output edge is meant to represent a typical load decoupling capacitor. Please contact Enpirion Applications Support for further details regarding radiated EMI testing. Input and Output Capacitors The input capacitance on the board is a 4.7uF 0603 MLCC. There is a pre-tinned pad that allows for an additional 0603 case size MLCC to experiment with input filter performance. The output capacitance on the board is a 10uF 0603 in parallel with a 1uF 0402. NOTE: Capacitors must be X5R or X7R dielectric formulations. Page 4 of 6 (c)Enpirion 2008 all rights reserved, E&OE Enpirion Confidential February 2010 Evaluation Board Schematic Input Protection 1 Vin TP8 2 Vin J2 1 + U2 N/U D1 C8 2 Vout J3 1 1 TP5 1 2 TP1 R2 R3 R5 R6 Vin C1 N/U 0603 FB1 PGND 3 NC3 4 VFB 5 13 AVIN ENABLE U1 NC9 EP5348UI 6 VOUT AGND NC8 12 J1 11 1 2 3 10 9 8 TP14 C3 C4 C9 Vout TP6 TP12 1 2 1 TP11 Short across R4 when all other routing complete R4 1 TP7 2 1 2 1 TP2 TP9 TP10 Figure 4. Evaluation Board Schematic and critical component values. R1 = 100k R2 = 150k for 1.0VOUT R3 = 60.4k for 1.59VOUT R5 = 49.9k for 1.8VOUT R6 = 33.2k for 2.41VOUT C9 = 10pF C2 = 4.7uF X5R 0603 C3 = 10uf X5R 0603 C4 = 1uF X5R 0402 Page 5 of 6 (c)Enpirion 2008 all rights reserved, E&OE Enpirion Confidential J5 1 2 3 0603 R1 ENABLE TP13 0603 0805 0805 TP15 PVIN VOUT 2 NC(SW)13 NC(SW)1 7 5 3 1 1 NC(SW)14 Place TP3 and TP4 around 100 mil apart J4 C10 0805 TP3 14 TP4 7 8 0805 0805 6 4 0805 2 0805 C2 0603 LLM February 2010 Contact Information Enpirion, Inc. Perryville III 53 Frontage Road, Suite 210 Hampton, NJ 08827 +1-908-894-6000 www.enpirion.com Enpirion reserves the right to make changes in circuit design and/or specifications at any time without notice. Information furnished by Enpirion is believed to be accurate and reliable. Enpirion assumes no responsibility for its use or for infringement of patents or other third party rights, which may result from its use. Enpirion products are not authorized for use in nuclear control systems, as critical components in life support systems or equipment used in hazardous environment without the express written authority from Enpirion. Page 6 of 6 (c)Enpirion 2008 all rights reserved, E&OE Enpirion Confidential