LM3424BKBSTEVAL/NOPB National Semiconductor, LM3424BKBSTEVAL/NOPB Datasheet - Page 8

• Manufacturer Part Number: LM3424BKBSTEVAL/NOPB
• Description: BOARD EVAL BUCK BOOST LM3424
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM3424BKBSTEVAL/NOPB

• Current - Output / Channel: 1A
• Outputs And Type: 1, Non-Isolated
• Features: Dimmable
• Voltage - Input: 10 ~ 70 V
• Utilized Ic / Part: LM3424
• Core Chip: LM3424
• Topology: Buck-Boost
• No. Of Outputs: 1
• Dimming Control Type: PWM / Analog
• Development Tool Type: Hardware - Eval/Demo Board
• Mcu Supported Families: LM3424 Family
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Other names: LM3424BKBSTEVAL

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Assume R
The chosen components from step 9 are:
10. INPUT CAPACITANCE
Solve for the minimum C
To minimize power supply interaction a 200% larger capaci-
tance of approximately 20 µF is used, therefore the actual
Δv
selection is limited, four 4.7 µF X7R capacitors are chosen.
Determine minimum allowable RMS current rating:
The chosen components from step 10 are:
11. NFET
Determine minimum Q1 voltage rating and current rating:
A 100V NFET is chosen with a current rating of 32A due to
the low R
The chosen component from step 11 is:
IN-PP
is much lower. Since high voltage ceramic capacitor
DS-ON
FS
= 10Ω and solve for C
= 50 mΩ. Determine I
IN
:
FS
T-RMS
:
and P
T
:
8
12. DIODE
Determine minimum D1 voltage rating and current rating:
A 100V diode is chosen with a current rating of 12A and V
600 mV. Determine P
The chosen component from step 12 is:
13. INPUT UVLO
Solve for R
The closest standard resistor is 150 kΩ therefore V
Solve for R
The closest standard resistor is 21 kΩ making V
The chosen components from step 13 are:
UV2
UV1
:
:
D
:
TURN-ON
HYS
is:
:
D
=