LM3409QHVMY/NOPB National Semiconductor, LM3409QHVMY/NOPB Datasheet - Page 21
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LM3409QHVMY/NOPB
Manufacturer Part Number
LM3409QHVMY/NOPB
Description
IC LED DVR HIGH BRIGHT 10MSOP
Manufacturer
National Semiconductor
Series
PowerWise®r
Datasheet
1.LM3409MYNOPB.pdf
(30 pages)
Specifications of LM3409QHVMY/NOPB
Constant Current
Yes
Topology
PWM, Step-Down (Buck)
Number Of Outputs
1
Internal Driver
No
Type - Primary
Automotive, General Purpose
Type - Secondary
High Brightness LED (HBLED)
Voltage - Supply
6 V ~ 75 V
Mounting Type
Surface Mount
Package / Case
10-TFSOP, 10-MSOP (0.118", 3.00mm Width) Exposed Pad
Operating Temperature
-40°C ~ 125°C
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Voltage - Output
-
Frequency
-
Current - Output / Channel
-
Other names
LM3409QHVMYTR
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Design Example #2
ANALOG DIMMING APPLICATION FOR 4 LEDS
SPECIFICATIONS
f
V
V
I
Δi
Δv
V
η = 0.90
1. NOMINAL SWITCHING FREQUENCY
Assume C
The closest 1% tolerance resistor is 15.4 kΩ therefore the
actual t
SW
LED
IN
O
TURN-ON
L-PP
IN-PP
= 14V
= 500kHz
= 24V; V
= 1A
= 450mA; Δi
OFF
= 1V
= 10V; V
OFF
and target f
IN-MAX
= 470pF and η = 0.90. Solve for R
HYS
= 42V
LED-PP
= 1.1V
SW
= 50mA
are:
OFF
:
21
The chosen components from step 1 are:
2. INDUCTOR RIPPLE CURRENT
Solve for L1:
The closest standard inductor value is 22 µH therefore the
actual Δi
The chosen component from step 2 is:
L-PP
is:
30085619
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