February 2010
Page 1 of 6
©Enpirion 2008 all rights rese rved, E&OE
Enpirion Confidential
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 (-).
February 2010
Page 2 of 6
©Enpirion 2008 all rights rese rved, E&OE
Enpirion Confidential
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.
February 2010
Page 3 of 6
©Enpirion 2008 all rights rese rved, E&OE
Enpirion Confidential
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.
February 2010
Page 4 of 6
©Enpirion 2008 all rights rese rved, E&OE
Enpirion Confidential
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 high-
frequency 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.
February 2010
Page 5 of 6
©Enpirion 2008 all rights rese rved, E&OE
Enpirion Confidential
Evaluation Board Schematic
C10
FB1
TP2
1
2
TP1
1
2
0603
0603
Vin
Vout
R4
TP9
1
2
TP10
1
2
Short across R4
when all other
routing complete
J1
1
2
3
TP6 1
TP11 TP12
J4
1
3
5
2
4
6
87
R3
TP81
R5
R6
TP51
ENABLE
0805
0805
0805
0805
R1
R2
+
C8
U2
N/U
Vin
C3
C4
TP71
D1
J5
1
2
3
U1
EP5348UI
NC(SW)1
1
PGND
2
NC3
3
VFB
4
AGND
5
VOUT
6
VOUT
7
PVIN 12
AVIN 11
ENABLE 10
NC9 9
NC8 8
NC(SW)14 14
NC(SW)13 13
LLM
TP14
TP13
TP15
C1 N/U
C2
0805
0603
0603
C9
0805
TP3TP4
Place TP3 and TP4
around 100 mil apart
0805
J2
1
2
J3
1
2
Vin
Vout
Input Protection
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
February 2010
Page 6 of 6
©Enpirion 2008 all rights rese rved, E&OE
Enpirion Confidential
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.