Enpirion
®
Power Evaluation Board User Guide
EN2340QI
PowerSoC
Test 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 (TP13 to TP16). 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 tip similar to the one shown below to
measure switching signals and input / output ripple to avoid noise coupling
into the probe ground lead. Input ripple, output ripple, and load transient
deviation are best measured near the respective input / output capacitors. For
more accurate ripple measurement, please see Enpirion App Note regarding
this subject.
4. The board includes a pull-up resistor for the POK signal and ready to monitor
the power OK status at clip lead marked POK.
5. The over-current protection circuit typically limits the maximum load current to
approximately 1.5X the rated value. For the EN2340, the OCP trip point can
be programmed via the RCLX pin. Table 1 below shows the RCLX value that
should be used to achieve a nominal 6A OCP trip point as a function of PVIN
& V
OUT
. The board as shipped is populated with a 31.6k
Ω RCLX resistor. If
the board does not deliver full load for some input and output combinations,
you may have to change the RCLX resistor according to Table 1. Please see
the datasheet for further details.
PVIN
V
OUT
Range
R
CLX
Value
5V
0.75V < V
OUT
≤
1.2V
30.1kΩ
1.2V < V
OUT
≤
2.0V
31.6kΩ
2.0V < V
OUT
≤
2.5V
33.2kΩ
8V
0.75V < V
OUT
≤
1.2V
30.9kΩ
1.2V < V
OUT
≤
2.0V
32.4kΩ
2.0V < V
OUT
≤
3.0V
35.7kΩ
3.0V < V
OUT
≤
4.0V
38.3kΩ
4.0V < V
OUT
≤
5.0V
40.2kΩ
12V
0.75V < V
OUT
≤
1.2V
31.6kΩ
1.2V < V
OUT
≤
2.0V
33.2kΩ
2.0V < V
OUT
≤
3.0V
36.5kΩ
3.0V < V
OUT
≤
4.0V
39.2kΩ
4.0V < V
OUT
≤
5.0V
41.2kΩ
Table 1: Recommended RCLX values
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