LM20333EVAL National Semiconductor, LM20333EVAL Datasheet - Page 3

• Manufacturer Part Number: LM20333EVAL
• Description: EVALUATION BOARD FOR THE LM20333
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM20333EVAL

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 3.3V
• Current - Output: 3A
• Voltage - Input: 4.5 ~ 25V
• Regulator Topology: Buck
• Board Type: Fully Populated
• Utilized Ic / Part: LM20333
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Power - Output: -
• Frequency - Switching: -

Performance Characteristics
EFFICIENCY PLOTS
Figure 1 shows the conversion efficiency versus output cur-
rent for a 5V and 12V input voltage.
TURN-ON WAVEFORM
When applying power to the LM20333 evaluation board a
soft-start sequence occurs. Figure 2 shows the output voltage
during a typical start-up sequence.
FIGURE 1.
FIGURE 2.
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3
OUTPUT RIPPLE WAVEFORM
Figure 3 shows the output voltage ripple. This measurement
was taken with the scope probe tip placed on the J3 load ter-
minal and the scope probe ground "barrel" pushed against the
J4 load terminal. The scope bandwidth is set to 20 MHz.
Bandwidth Limit = 20 MHz
PRIMARY SWITCHNODE WAVEFORM
FIGURE 4 shows the typical SW pin voltage while synchro-
nizing to an external source.
OUTPUT TRANSIENT RESPONSE
FIGURE 5 shows the output transient response durning a
300mA to 3A transient.
FIGURE 3.
FIGURE 4.
FIGURE 5.
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