FAN7346: 4-Channel LED Current Balance Controller for Lighting

The FAN7346 is an LED current-balance controller that controls 4-LED arrays to maintain equal LED current.

The FAN7346 has a high withstanding voltage, so is suitable for edge-type LED BLU and LED Lighting. To minimize components between primary to secondary, the FAN7346 generates a new integrated feedback signal.

The FAN7346 provides various protections, such as over-voltage regulation, open-LED protection, thermal protection, and drain-source voltage protection of regulating switch (the FAN7346 monitors all LED arrays drain-source voltage for protection). To increase system reliability, FAN7346 applies individual string protection. Because FAN7346 integrates so many functions it reduces overall BOM costs.

LED brightness can be linearly varied up to LED current by applying an external Pulse Width Modulated (PWM) signal to the PWM pin.

The FAN7346 is available in a 28-SOIC package.

Features

• Linear Balance Control for 4-Channel LED Arrays
• Wide LED String Voltage Range: ≤ 100V
• Wide V_CC Voltage: 10.5V to 35V
• External Linear Regulation Switch: MOSFET or BJT
• Internal Voltage Regulator for Feedback
• Monitoring Drain-Source Voltage of External Switch
• Precision Current Accuracy Trimmed to 1.5%
• Supports External PWM Dimming - Positive
• Supports Wide Dimming Ratio: 0.5%~100%
• Adaptive Linear Regulation Method
• Generate Integrated Feedback Signal for Primary Controller (Current Feedback + PWM Dimming)
• High Efficiency by Primary Side Direct Feedback
• Thermal Shutdown (Auto-Recovery)
• Over-Voltage Regulation
• Channel Individual Open-LED Protection
• Channel Individual Short-LED Protection
• Channel Individual Over-Current Protection
• Error Flag Output
• 28-Pin SOIC

Application Notes