Test Circuit and Layout Guidelines
01280322
C
C
- 22 µF, 50V Tantalum, Sprague “199D Series”
IN
- 47 µF, 25V Tantalum, Sprague “595D Series”
OUT
D1 - 3.3A, 50V Schottky Rectifier, IR 30WQ05F
L1 - 68 µH Sumida #RCR110D-680L
C
B
- 0.01 µF, 50V Ceramic
FIGURE 2. Standard Test Circuits and Layout Guides
Fixed Output Voltage Versions
01280323
C
C
- 22 µF, 50V Tantalum, Sprague “199D Series”
IN
- 47 µF, 25V Tantalum, Sprague “595D Series”
OUT
D1 - 3.3A, 50V Schottky Rectifier, IR 30WQ05F
L1 - 68 µH Sumida #RCR110D-680L
R1 - 1.5 kΩ, 1%
C
B
- 0.01 µF, 50V Ceramic
For a 5V output, select R2 to be 4.75 kΩ, 1%
where V
= 1.21V
REF
Use a 1% resistor for best stability.
FIGURE 3. Standard Test Circuits and Layout Guides
Adjustable Output Voltage Version
9
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