LM3429MH/NOPB National Semiconductor, LM3429MH/NOPB Datasheet - Page 23

• Manufacturer Part Number: LM3429MH/NOPB
• Description: IC LED DRVR HP CONS CURR 14TSSOP
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: High Power, Constant Currentr

Specifications of LM3429MH/NOPB

• Constant Current: Yes
• Topology: PWM, SEPIC, Step-Down (Buck), Step-Up (Boost)
• Number Of Outputs: 1
• Internal Driver: No
• Type - Primary: Automotive
• Type - Secondary: High Brightness LED (HBLED)
• Frequency: 2MHz
• Voltage - Supply: 4.5 V ~ 75 V
• Mounting Type: Surface Mount
• Package / Case: 14-TSSOP Exposed Pad, 14-eTSSOP 14-HTSSOP
• Operating Temperature: -40°C ~ 125°C
• Current - Output / Channel: 1A
• Internal Switch(s): No
• Efficiency: 95%
• For Use With: LM3429BSTEVAL - BOARD EVAL FOR BOOST LM3429LM3429BKBSTEVAL - BOARD EVAL FOR BUCK-BOOST LM3429
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Other names: LM3429MH

3. AVERAGE LED CURRENT
Solve for R
Assume R
The closest standard resistor for R
R
The chosen components from step 3 are:
4. INDUCTOR RIPPLE CURRENT
Solve for L1:
The closest standard inductor is 33 µH therefore the actual
Δi
Determine minimum allowable RMS current rating:
The chosen component from step 4 is:
HSP
L-PP
is actually 1 kΩ therefore I
is:
CSH
SNS
:
= 12.4 kΩ and solve for R
LED
SNS
is:
is actually 0.1Ω and for
HSP
:
23
5. OUTPUT CAPACITANCE
Solve for C
The closest standard capacitor is 6.8 µF therefore the actual
Δi
Determine minimum allowable RMS current rating:
The chosen components from step 5 are:
6. PEAK CURRENT LIMIT
Solve for R
The closest standard resistor is 0.04 Ω therefore I
The chosen component from step 6 is:
7. LOOP COMPENSATION
ω
ω
P1
Z1
LED-PP
is approximated:
is approximated:
is:
O
LIM
:
:
www.national.com
LIM
is: