Linear LT3597 60V triple step-down LED driver solution

Linear’s LT3597 is a 60V three-way step-down LED driver that provides 10,000:1 digital PWM dimming at 100Hz. Each channel can drive up to 10 LEDs. The switching frequency can be programmed between 200kHz and 1MHz. Adaptive control output For best efficiency, 2% LED current matching between channels, open LED reporting, short LED protection, programmable LED current and programmable temperature protection. The LT3597 can be used in LED signal boards, single color, multicolor and full color LED displays , large screen Display LED backlight and automotive, industrial and medical displays. This article introduces the main features of LT3597, block diagram and various application circuit diagrams.

The LTR3597 is a 60V triple step-down LED driver capable of achieving 10,000:1 digital PWM dimming at 100Hz with fast NPN current sources driving up to 10 LEDs in each channel. LED dimming can also be achieved via analog control of the CTRL1-3 pin.

The step-down switching frequency is programmed between 200kHz and 1MHz. The frequency is also synchronizable to an external clock. The LT3597 provides maximum LED brightness while adhering to manufacturers’ specifications for thermal derating. The derate temperature is programmed by placing a negative temperature coefficient (NTC) resistor on the master control pin.

The LT3597 adaptively controls VOUT in order to achieve optimal efficiency. Other features include: 2% LED current matching between channels, open LED reporting, shortened LED protection, programmable LED current, and programmable temperature protection.

LT3597 main features:

Three 100mA Buck Regulators, Each Drives Up to 10 LEDs with Fast NPN Current Sources

Fast Current Sources for <1μs Pulse Widths (10,000:1 True Color PWM™ Dimming at 100Hz)

LEDs Disconnected in Shutdown

Adaptive VOUT for Increased Efficiency

6V to 60V Input Voltage Range

±2% LED Current Matching

External Resistor Sets LED Current for Each Channel

Internal Compensation and Soft-Start

Programmable Switching Frequency (200kHz to 1MHz)

Synchronizable to External Clock

Open LED Detection and Reporting

Shorted LED Pin Protection and Reporting

Programmable LED Thermal Derating

Programmable Temperature Protection

5mmx 8mm Thermally Enhanced QFN Package with a 0.6mm High Voltage Pin Spacing

LT3597 application:

LED Billboards and Signboards

Mono, Multi, Full-Color LED Displays

Large Screen Display LED Backlighting

Automotive, Industrial, and Medical Displays
Linear LT3597 60V triple step-down LED driver solution
Figure 1. LT3597 block diagram
Linear LT3597 60V triple step-down LED driver solution
Figure 2. LT3597 three-way RGB single-pixel 100mA LED driver circuit diagram
Linear LT3597 60V triple step-down LED driver solution
Figure 3. LT3597 48V 1MHz step-down 100mA RGB LED driver circuit diagram

Linear LT3597 60V triple step-down LED driver solution
Figure 4. LT3597 48V 1MHz step-down 10W 100mA RGB LED driver circuit diagram (3.6V LED)
Linear LT3597 60V triple step-down LED driver solution
Figure 5. LT3597 24V 200kHz triple step-down 100mA RGB LED driver circuit diagram

Figure 6. LT3597 48V 1MHz triple step-down 20mA RGB LED driver circuit diagram
For details, see:
http://cds.linear.com/docs/Datasheet/3597f.pdf

The Links:   LM170E03-TLHB FF600R17ME4