Linear Technology LT3791, 4.7V-60V input to drive 25V of LEDs at 2A (scalable to 100W) DC1666A DC1666A 데이터 시트

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dc1666af

DEMO MANUAL DC1666A

Demonstration circuit DC1666A is easy to set up to evaluate 

the performance of the LT3791. Follow the procedure below: 
NOTE: PWM must be pulled high to run. If PWM is not 

used, connect PWM to a 5V source or to INTV

CC

 on the 

PCB using 0Ω resistor R22.
1.  Connect a string of LEDs that will run with forward volt-

age less than 25.5V, but greater than 9.5V, to the LED

+ 

and LED

–

 terminals on the PCB as shown in Figure 1.

2. Connect the EN/UVLO terminal to GND.
3. With power off, connect the input power supply to the 

PVIN and GND terminals. Make sure that the PVIN DC 

input voltage will not exceed 60V.

4.  Connect the PWM terminal. If PWM is not used, connect 

PWM to a 5V source or to INTV

CC

 on the PCB using 0Ω 

resistor R22. PWM must be pulled high to run.

5. Turn the input power supply on and make sure the 

voltage is between 4.7V and 60V.

6. Release the EN/UVLO to GND connection.
7. Observe the LED string running at the programmed 

LED current.

8.  For PWM dimming, connect a PWM (100Hz or higher is 

recommended) signal to the PWM terminal. For analog 

dimming, connect a DC voltage between 0V and 2V to 

the CTRL terminal.

9. Observe the reduction of brightness in the LED string 

when PWM or analog dimming.