The PT4115B89E-B 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-B 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. The 'B' likely signifies a specific revision or minor variation of the original PT4115B89E.

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-B 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. Datasheets should be consulted for the exact differences between the PT4115B89E and the PT4115B89E-B.