PT4115B89E 30V 1.2A Step-Down High Brightness Led Driver IC SOT-89-5

PT4115B89E 30V 1.2A Step-Down High Brightness LED Driver IC SOT-89-5 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 total LED chain voltage. This monolithic integrated circuit operates from an input supply between 6 V and 30 V while delivering an externally adjustable output current up to 1.2 A. Furthermore, the device incorporates a dedicated DIM pin that accepts either a DC voltage or a wide range of PWM signals for precise linear and pulse-width modulation dimming. Consequently, engineers can achieve high-efficiency thermal management and superior brightness control in compact lighting solutions. Therefore, the PT4115B89E stands out as a robust choice for modern high-power LED applications where space and power conversion efficiency remain critical priorities.

Key Features:

• High Efficiency: This driver achieves up to 95% efficiency, which significantly reduces heat dissipation in high-power lighting systems.
• Wide Input Range: The IC supports a broad supply voltage from 6 V up to 30 V, accommodating various power bus architectures.
• Flexible Dimming: It provides multi-functional dimming capabilities via the DIM pin, supporting both analog DC voltage and PWM signals.
• Inherent LED Protection: The chip includes integrated open-circuit LED protection and thermal shutdown circuitry to ensure long-term system reliability.
• Hysteretic Control: Utilizes a hysteretic control scheme that requires no external compensation, however, it maintains excellent load regulation and fast transient response.

Technical Specifications:

• Input Voltage Range (V_IN): 6 V to 30 V
• Maximum Output Current: 1.2 A (Set via external sense resistor)
• Current Accuracy: ±5% typical
• Switching Frequency: Up to 1 MHz
• Dimming Ratio: ≈ 5000:1 (PWM at 100 Hz)
• Output Current Temperature Coefficient: ±200 ppm/°C
• Operating Temperature: −40°C to +85°C

Mechanical Specifications:

• Package Type: SOT-89-5 (Surface Mount Device)
• Lead Finish: Matte Tin / Lead-Free (RoHS Compliant)
• Moisture Sensitivity Level: MSL 3
• Thermal Resistance (θ_JA): ≈ 45 °C/W (Depending on PCB copper area)

Dimensions:

• Body Length: ≈ 4.5 mm
• Body Width: ≈ 2.5 mm (Excluding leads)
• Overall Width: ≈ 4.2 mm (Including leads)
• Package Height: ≈ 1.5 mm
• Pin Pitch: 1.5 mm (Center pins)

Pinout and Wiring:

• Pin 1 (SW): Connect to the drain of the internal power MOSFET and the inductor/freewheeling diode.
• Pin 2 (GND): Connect to the system ground.
• Pin 3 (DIM): Input for dimming control. Leave floating for full brightness or apply PWM/DC voltage.
• Pin 4 (CSN): Current sense input. Connect the sense resistor between VIN and this pin.
• Pin 5 (VIN): Supply voltage input. Additionally, place a high-quality ceramic bypass capacitor very close to this pin.

Datasheet Reference:

• Download PowTech PT4115B89E Datasheet

Commonly Used in:

• LED Driver Modules: Serving as the primary controller for adjustable constant current buck converters.
• MR16/GU10 Lamps: Powering high-brightness LED replacements for halogen spotlights.
• Automotive Lighting: Providing stable current for interior and decorative vehicle lighting.

Applications:

• General Illumination: Driving high-power LED arrays in domestic and commercial fixtures.
• Backlighting: Regulating current for large-scale LCD backlighting units.
• Signage and Displays: Managing brightness for LED billboards and traffic signals.
• Portable Lighting: Operating high-efficiency flashlights and emergency lanterns.

Equivalent Models:

• AL8805: A popular alternative from Diodes Inc. with similar voltage and current ratings in SOT-89-5.
• ZXLD1360: This model often serves lower current applications while maintaining a similar hysteretic architecture.
• XL3001: A common substitute often found in low-cost LED driver modules with comparable buck characteristics.

Package Includes:

• 1 x PT4115B89E 30V 1.2A Step-Down High Brightness Led Driver IC SOT-89-5