LM3414SDX National Semiconductor Corporation, LM3414SDX Datasheet - Page 11

• Manufacturer Part Number: LM3414SDX
• Description: Lm3414/lm3414hv 1a 60w* Common Anode Capable Constant Current Buck Led Driver Requires No External Current Sensing Resistor
• Manufacturer: National Semiconductor Corporation

Block Diagram
Operation Description
OVERVIEW
The LM3414/14HV is a high power floating buck LED driver
with wide input voltage ranges. It requires no external current
sensing elements and loop compensation networks. The in-
tegrated power N-MOSFET enables high output power with
up to 1000 mA output current. The combination of Pulse Width
Modulation (PWM) control architecture and the proprietary
Pulse Level Modulation (PLM) guarantees accurate current
regulation, good EMI performance and provides high flexibil-
ity on inductor selection. High speed dimming control input
allows precision and high resolution brightness control for ap-
plications require fine brightness adjustment.
11
Application Information
SETTING THE SWITCHING FREQUENCY
Both the LM3414 and LM3414HV are PWM LED drivers that
contain a clock generator to generate constant switching fre-
quency for the device. The switching frequency is determined
by the resistance of an external resistor R
250 kHz to 1 MHz. Lower resistance of R
switching frequency. The switching frequency of the
LM3414/14HV is governed by the following equation:
FS
FS
results in higher
in the range of
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