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 V
• OUT 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
• 5mm × 8mm Thermally Enhanced QFN Package with a 0.6mm High Voltage Pin Spacing

Typical Application

Description

The LT3597 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, shorted LED protection, programmable LED current, and programmable temperature protection.