Features
- For new designs we recommend the LT3755-2 instead of the LT3755
- Click Here For LT3755 Evaluation Kit
- 3000:1 True Color PWM™ Dimming
- Wide Input Voltage Range: 4.5V to 40V
- Output Voltage Up to 75V
- Constant-Current and Constant-Voltage Regulation
- 100mV High Side Current Sense
- Drives LEDs in Boost, Buck Mode, Buck-Boost Mode, SEPIC or Flyback Topology
- Adjustable Frequency: 100kHz to 1MHz
- Open LED Protection
- Programmable Undervoltage Lockout with Hysteresis
- Improved Open LED Status Pin (LT3755-2)
- Frequency Synchronization (LT3755-1)
- PWM Disconnect Switch Driver
- CTRL Pin Provides Analog Dimming
- Low Shutdown Current: <1μA
- Programmable Soft-Start
- Thermally Enhanced 16-Lead QFN (3mm × 3mm) and MSOP Packages
Description
The LT3755, LT3755-1 and LT3755-2 are DC/DC controllers designed to operate as a constant-current source for driving high current LEDs. They drive a low side external N-channel power MOSFET from an internal regulated 7V supply. The fixed frequency, current-mode architecture results in stable operation over a wide range of supply and output voltages. A ground referenced voltage FB pin serves as the input for several LED protection features, and also makes it possible for the converter to operate as a constant-voltage source. A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance or external component size.
The LT3755/LT3755-1/LT3755-2 sense output current at the high side of the LED string. High side current sensing is the most flexible scheme for driving LEDs, allowing boost, buck mode or buck-boost mode configuration. The PWM input provides LED dimming ratios of up to 3000:1, and the CTRL input provides additional analog dimming capability. These parts are available in the 16-lead (3mm × 3mm) QFN and MSOP packages.
Order Info
Package Variations and Pricing
| Part Number |
Package |
Pins |
Temp |
Price (1-99) |
Price (1k)* |
RoHS Data |
| LT3755EMSE#PBF |
MSOP |
16 |
E |
$4.07 |
$2.85 |
View |
| LT3755EMSE#TRPBF |
MSOP |
16 |
E |
|
$2.91 |
View |
| LT3755EMSE-1#PBF |
MSOP |
16 |
E |
$4.07 |
$2.85 |
View |
| LT3755EMSE-1#TRPBF |
MSOP |
16 |
E |
|
$2.91 |
View |
| LT3755EMSE-2#PBF |
MSOP |
16 |
E |
$4.07 |
$2.85 |
View |
| LT3755EMSE-2#TRPBF |
MSOP |
16 |
E |
|
$2.91 |
View |
| LT3755EUD#PBF |
QFN |
16 |
E |
$3.93 |
$2.75 |
View |
| LT3755EUD#TRPBF |
QFN |
16 |
E |
|
$2.81 |
View |
| LT3755EUD-1#PBF |
QFN |
16 |
E |
$3.93 |
$2.75 |
View |
| LT3755EUD-1#TRPBF |
QFN |
16 |
E |
|
$2.81 |
View |
| LT3755EUD-2#PBF |
QFN |
16 |
E |
$3.93 |
$2.75 |
View |
| LT3755EUD-2#TRPBF |
QFN |
16 |
E |
|
$2.81 |
View |
| LT3755IMSE#PBF |
MSOP |
16 |
I |
$4.64 |
$3.25 |
View |
| LT3755IMSE#TRPBF |
MSOP |
16 |
I |
|
$3.31 |
View |
| LT3755IMSE-1#PBF |
MSOP |
16 |
I |
$4.64 |
$3.25 |
View |
| LT3755IMSE-1#TRPBF |
MSOP |
16 |
I |
|
$3.31 |
View |
| LT3755IMSE-2#PBF |
MSOP |
16 |
I |
$4.64 |
$3.25 |
View |
| LT3755IMSE-2#TRPBF |
MSOP |
16 |
I |
|
$3.31 |
View |
| LT3755IUD#PBF |
QFN |
16 |
I |
$4.50 |
$3.15 |
View |
| LT3755IUD#TRPBF |
QFN |
16 |
I |
|
$3.21 |
View |
| LT3755IUD-1#PBF |
QFN |
16 |
I |
$4.50 |
$3.15 |
View |
| LT3755IUD-1#TRPBF |
QFN |
16 |
I |
|
$3.21 |
View |
| LT3755IUD-2#PBF |
QFN |
16 |
I |
$4.50 |
$3.15 |
View |
| LT3755IUD-2#TRPBF |
QFN |
16 |
I |
|
$3.21 |
View |
| Buy Now |
| Request Samples |
* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology
sales office or authorized distributor.
Evaluation Kits
| Part Number |
Description |
Price |
| DC1268B-A |
LT3755EUD-2 Demo Board| 40V/75V Full-Featured LED Controller |
$175.00 |
| DC1268B-B |
LT3755EUD-1 Demo Board | 40V/75V Full-Featured LED Controller |
$175.00 |
|
Buy Now
|
Simulate
To simulate selected Linear Technology products, please download LTSpice / SwitcherCAD III. This powerful schematic capture and simulation tool includes macro models for 80% of Linear Technology's switching regulators, over 200 op amp models, as well as resistors, transistors and MOSFET models.
For other simulation tools, visit our Design Simulation and Device Models page.