The PT4115B89E is a continuous conduction mode inductive step-down converter, designed for driving single or multiple series connected LEDs efficiently from a voltage source higher than the LED voltage. It operates from an input voltage range of 8V to 30V and provides an externally adjustable output current of up to 1.2A. The PT4115B89E integrates a high-side power MOSFET and uses an external resistor to set the output current. Dimming can be achieved by applying a PWM signal to the EN pin. The device is available in a compact SOT89-5 package.
Applications
- LED Lighting
- General Purpose Constant Current Source
- Automotive Lighting
- Backlighting
Features
- Simple and low cost high efficiency LED driver
- Few external components
- Wide input voltage range: 8V to 30V
- Up to 1.2A output current
- High efficiency (up to 97%)
- PWM dimming
- Built-in over temperature protection
- Available in SOT89-5 package
Benefits
- Provides a cost-effective solution for driving LEDs
- High efficiency operation minimizes power dissipation
- Wide input voltage range allows for flexible application
- Adjustable output current allows for driving various types and configurations of LEDs
- PWM dimming enables precise control of LED brightness
- Integrated protection features enhance system reliability
- Small package size minimizes board space requirements
Additional Details
The PT4115B89E utilizes a hysteretic control scheme, which provides inherent stability and fast transient response. The output current is regulated by sensing the voltage across an external sense resistor connected in series with the LED string. The device includes over-temperature protection to prevent damage in the event of excessive heat. The switching frequency is typically around 1MHz, enabling the use of small external components.