LM3429BSTEVAL/NOPB National Semiconductor, LM3429BSTEVAL/NOPB Datasheet - Page 22

• Manufacturer Part Number: LM3429BSTEVAL/NOPB
• Description: BOARD EVAL FOR BOOST LM3429
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM3429BSTEVAL/NOPB

• Current - Output / Channel: 1A
• Outputs And Type: 1, Non-Isolated
• Features: Dimmable
• Voltage - Input: 10 ~ 26 V
• Utilized Ic / Part: LM3429
• Core Chip: LM3429
• Topology: Buck-Boost
• No. Of Outputs: 1
• Dimming Control Type: PWM / Analog
• Development Tool Type: Hardware - Eval/Demo Board
• Mcu Supported Families: LM3429 Family
• Msl: MSL 1 - Unlimited
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption
• Voltage - Output: -
• Other names: *LM3429BSTEVAL; *LM3429BSTEVAL/NOPB; LM3429BSTEVAL

www.national.com
Design Example #1
BUCK-BOOST APPLICATION - 6 LEDs at 1A
SPECIFICATIONS
N = 6
V
r
V
V
V
f
V
I
Δi
Δi
Δv
I
V
V
V
V
1. OPERATING POINT
Solve for V
SW
LED
LIM
LED
LED
IN
IN-MIN
IN-MAX
SNS
TURN-ON
HYS
TURN-OFF
HYSO
L-PP
LED-PP
IN-PP
= 24V
= 700 kHz
= 6A
= 1A
= 325 mΩ
= 3.5V
= 100 mV
= 3V
= 500 mA
= 10V
= 10V
= 1V
= 70V
= 50 mA
= 10V
= 40V
O
and r
D
:
22
Solve for D, D', D
2. SWITCHING FREQUENCY
Assume C
The closest standard resistor is actually 35.7 kΩ therefore the
f
The chosen components from step 2 are:
SW
is:
T
= 1 nF and solve for R
MAX
, and D
MIN
:
T
:
300944i1