DC1573A Analog Devices

DEMO MANUAL DC1573A LT3760 8-Channel 100mA High Voltage LED Driver Description DC1573A is an 8-Channel 100mA High Voltage LED Driver The LT3760 data sheet gives a complete description of featuring the LT 3760. The LT3760 drives up to 100mA the part, operation and applications information. The data per string and has a maximum LED string voltage of 45V. sheet must be read in conjunction with this demo manual DC1573A is set at 1MHz switching frequency for smallest for demonstration circuit 1573A. The LT3760 is assembled inductor and capacitor size as well as maximum PWM in a small 28-lead FE (4.4mm TSSOP) package with a dimming performance. Overvoltage protection is set at thermally enhanced ground pad. Proper board layout is 55V in case the LEDs are removed from the circuit. If the essential for maximum thermal performance. See the LEDs are opened, the FAULT terminal output flag goes Layout Considerations section in the data sheet. low and reports the fault condition. The V terminal is IN Design files for this circuit board are available at powered from 10V to 14V input separated from the 24V DEMO MANUAL DC1573A q Uick st Art proce DU Demonstration circuit 1573A is easy to set up to evaluate 4. With power off, connect the V power supply to the IN the performance of the LT3760. Follow the procedure below: V and GND terminals within the range specified on IN the PCB. Note: PWM must be pulled high to work. If PWM is not used, tie PWM high or connect to REF on the PCB using 5. Connect the PWM terminal. If PWM is not used, tie PWM resistor R9. high or connect to REF on the PCB using resistor R9. PWM must be pulled high to work. 1. Connect strings of LEDs with forward voltage less than 45V, but greater than the PV voltage, to the LED+ and 6. Turn the PV power supply on. IN IN LED1-8 terminals on the PCB as shown in Figure 1. Tie 7. Turn the V power supply on after PV . IN IN any unused LED1-8 pins directly to V (LED+) before OUT 8. Release the SHDN-to-GND connection. power-up to disable that channel. 9. Observe the LED strings running at the programmed 2. Connect the SHDN terminal to GND. LED current. 3. With power off, connect the PV power supply to the IN Note: For PWM dimming, connect a PWM (100Hz or higher) PV and GND terminals within the range specified on IN signal to the PWM terminal and observe the reduction of the PCB. Make sure that the PV DC input voltage does IN brightness in the LED string when PWM dimming. not exceed the forward voltage of the LED string. Figure 1. Proper Measurement Setup Drawing dc1573af 2 re