LM3424BSTEVAL/NOPB National Semiconductor, LM3424BSTEVAL/NOPB Datasheet - Page 6

• Manufacturer Part Number: LM3424BSTEVAL/NOPB
• Description: BOARD EVAL BOOST LM3424
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM3424BSTEVAL/NOPB

• Current - Output / Channel: 1A
• Outputs And Type: 1, Non-Isolated
• Features: Dimmable
• Voltage - Input: 10 ~ 26 V
• Utilized Ic / Part: LM3424
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Other names: LM3424BSTEVAL

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Design Procedure
SPECIFICATIONS
N = 6
V
r
V
V
V
f
V
I
Δi
Δi
Δv
I
V
V
V
V
T
T
t
1. OPERATING POINT
Solve for V
Solve for D, D', D
2. SWITCHING FREQUENCY
Solve for R
The closest standard resistor is 14.3 kΩ therefore f
SW
LED
LIM
TSU
LED
BK
END
LED
IN
IN-MIN
IN-MAX
SNS
TURN-ON
HYS
TURN-OFF
HYSO
L-PP
LED-PP
IN-PP
= 24V
= 500 kHz
= 6A
= 70°C
= 1A
= 325 mΩ
= 30 ms
= 120°C
= 3.5V
= 100 mV
= 3V
= 700 mA
= 10V
= 10V
= 100 mV
= 70V
= 12 mA
= 10V
= 40V
O
T
:
and r
MAX
D
:
, and D
MIN
:
SW
is:
6
The chosen component from step 2 is:
3. AVERAGE LED CURRENT
Solve for R
Assume R
The closest standard resistor for R
R
The chosen components from step 3 are:
4. THERMAL FOLDBACK
Using a standard 100k NTC thermistor (connected to pins 4
and ll), find the resistances corresponding to T
(R
manufacturer's datasheet. Assuming R
49.9 kΩ, then R
Solve for R
The chosen components from step 4 are:
HSP
NTC-BK
is actually 1 kΩ therefore I
= 243 kΩ and R
CSH
SNS
GAIN
:
= 12.4 kΩ and solve for R
:
BIAS
= R
NTC-BK
NTC-END
= 243 kΩ.
LED
SNS
is:
is actually 0.1Ω and for
= 71.5 kΩ) from the
HSP
REF1
:
BK
= R
and T
REF2
END
=