Analog Devices LT3796

Description

The LT®3796/LT3796-1 are DC/DC controllers designed to regulate a constant-current or constant-voltage and are ideal for driving LEDs. The fixed frequency and current mode architecture result in stable operation over a wide range of supply and output voltages. Two ground referredvoltage FB pins serve as the input for several LED protection features, and also allow the converter to operate as a constant-voltage source. The LT3796/LT3796-1 feature a programmable threshold output current sense amplifier with rail-to-rail common mode range. A separate high side amplifier is gain configurable with two resistors and can be used to regulate a second current or a voltage in combination with one of the FB pins. The PWM input provides LED dimming ratios of up to 3000:1.The LT3796-1 is optimized for a second output current regulation loop that can be enabled/disabled with a PMOS switch, either to drive a second LED string or to extend analog dimming range.

Features

• 3000:1 True Color PWM™ Dimming
• Wide Input Voltage Range: 6V to 100V
• Current Monitoring Up to 100V
• High Side PMOS Disconnect and PWM Switch Driver
• Constant-Current and Constant-Voltage Regulation
• Dual Current Sense Amplifiers with Reporting
• C/10 Detection for Battery and SuperCap Charging
• Linear Current Sense Threshold Programming
• Short-Circuit Protection
• Adjustable Frequency: 100kHz to 1MHz
• Frequency Synchronization (LT3796)
• Independent Top Gate Enable Pin (LT3796-1)
• Programmable Open LED Protection with VMODE Flag
• Programmable Undervoltage Lockout with Hysteresis
• Soft-Start with Programmable Fault Restart Timer
• Available in 28-Lead TSSOP Package

Typical applications

• High Power LED, High Voltage LED, Dual String
• Accurate Current Limited Voltage Regulators
• Battery and SuperCap Chargers

More information

• Datasheet
• IC product information