FAN5702 Configurable 180mA, 6-Channel LED Driver with 12C Control for Mobile Handsets
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August 2010 © 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN5702 • Rev. 1.0.3 FAN5702 — Configurable 180mA 6-LED Driver with I2C Control FAN5702 Configurable 180mA 6-LED Driver with I2C Control Features .. Six (6) Parallel LEDs (up to 30mA Each) .. Total Package Load Current Capability: 180mA .. Group from 2 to 6 LEDs for Flexible Backlighting .. I2C Interface for Easy Programming .. >600:1 Dimming Ratio for 100Hz PWM Frequency .. Logarithmically Controlled Dimming with 64 Steps .. Secondary Brightness Control Using PWM Dimming up to 20kHz in Conjunction with I2C Dimming - Dynamic Backlight Control (DBC) to Reduce Current Consumption .. Up to 92% Efficiency .. Built-in 1.5x Charge Pump with Low Drop-Out Bypass Switch and automatic switching to 1x mode .. 1.2MHz Switching Frequency for Small-Sized Capacitors .. 16-Bump 1.6mm × 1.6mm WLCSP (0.6mm Height) .. 16-Lead 3.0mm x 3.0mm UMLP (0.55mm Height) Applications .. LCD Backlighting .. Mobile Handsets / Smartphones .. Portable Media Players Description The FAN5702 is a highly integrated and configurable chargepump- based multi-LED driver. The device can drive up to six LEDs in parallel with a total output current of 180mA. Regulated internal current sinks deliver excellent current and brightness matching to all LEDs. The FAN5702 has an I2C interface that allows the user to independently control the brightness with a default grouping of 2,1,1,1,1 for a maximum of five independent lighting channels. The LED driver can be programmed in a multitude of configurations to address broad lighting requirements for different platforms. Each LED can be configured through I2C as five independent channels (Group A has two LEDs by default) or any additional LEDs can join Group A to increase the backlighting needs as the display size increases. The device offers a second dimming control using the EN/PWM pin. Applying a PWM dimming signal to this pin allows control of the dimming of Group A LEDs so that the average current is the linear value multiplied by the PWM dimming duty-cycle. The device provides excellent efficiency, without an inductor, by operating the charge pump in 1.5x or pass-through mode. The FAN5702 can be ordered with default ISET values of 30mA, 20mA, 15mA, or 8mA. The default ISET is always determined by the ISET ordered (see Ordering Information). Ordering Information Part Number LED Current (ISET) Temperature Range Package Packing FAN5702UC30X 30mA -40 to 85°C WLCSP-16, 0.4mm Pitch Tape and Reel FAN5702UC20X 20mA -40 to 85°C WLCSP-16, 0.4mm Pitch Tape and Reel FAN5702UC15X 15mA -40 to 85°C WLCSP-16, 0.4mm Pitch Tape and Reel FAN5702UC08X 8mA -40 to 85°C WLCSP-16, 0.4mm Pitch Tape and Reel FAN5702UMP30X 30mA -40 to 85°C UMLP-16, 3.0 x 3.0 x 0.55mm Tape and Reel FAN5702UMP20X 20mA -40 to 85°C UMLP-16, 3.0 x 3.0 x 0.55mm Tape and Reel FAN5702UMP15X 15mA -40 to 85°C UMLP-16, 3.0 x 3.0 x 0.55mm Tape and Reel FAN5702UMP08X 8mA -40 to 85°C UMLP-16, 3.0 x 3.0 x 0.55mm Tape and Reel

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN5702 • Rev. 1.0.3 2 FAN5702 — Configurable 180mA 6-LED Driver with I2C Control Typical Application Figure 1. Typical Application

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN5702 • Rev. 1.0.3 3 FAN5702 — Configurable 180mA 6-LED Driver with I2C Control WLCSP Pin Configuration C1 B1 A1 A2 C3 B3 A3 C2 D1 D2 D3 B2 A4 C4 D4 B4 Bumps Facing Down C4 B4 A4 C3 B3 A3 D4 D3 C1 B1 A2 A1 C2 D2 D1 B2 Bumps Facing Up Figure 2. WLCSP-16, 0.4mm Pitch, 1.61 x 1.61mm Pin Definitions Pin # Name Description D2 VIN Input Supply Voltage. Connect to 2.7 – 5.5VDC input power source. B4 GND Ground D1 VOUT Charge Pump Output Voltage. Connect to LED anodes. D3 ,D4 C1+, C1– Charge pump flying capacitor #1 C3, C4 C2+, C2–...

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN5702 • Rev. 1.0.3 4 FAN5702 — Configurable 180mA 6-LED Driver with I2C Control UMLP Pin Configuration Bottom View Figure 3. UMLP-16, 0.5mm Pitch, 3mm x 3mm Pin Definitions Pin # Name Description 11 VIN Input Supply Voltage. Connect to 2.7 – 5.5VDC input power source. 6 GND Ground 12 VOUT Charge Pump Output Voltage. Connect to LED anodes. 10,9 C1+, C1– Charge pump flying capacitor #1 8,7 C2+, C2– Charge pump flying capacitor #2 1, 2 15, 16 13, 14 D2A, D1A D4,D3 D6,D5 LED Outputs 4 EN / PWM Enable / PWM dimming input. By...

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN5702 • Rev. 1.0.3 5 FAN5702 — Configurable 180mA 6-LED Driver with I2C Control Absolute Maximum Ratings Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Symbol Parameter Min. Max. Units VCC...

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN5702 • Rev. 1.0.3 6 FAN5702 — Configurable 180mA 6-LED Driver with I2C Control Electrical Specifications Unless otherwise specified: VIN = 2.7V to 5.5V; TA = -40°C to +85°C; and ENA, EN3, EN4, EN5, and EN6 = 1. Typical values are VIN = 3.6V, TA = 25°C, ILED = 20mA, and LED cathode terminals = 0.4V. Circuit and components are according to Figure 1. Symbol Parameter Conditions Min. Typ. Max. Units Power Supplies and Thermal Protection IQ Quiescent Supply Current 1.5x Mode, No LEDs 4.4 mA 1x Mode, No LEDs 0.3 mA ISD Shutdown...

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN5702 • Rev. 1.0.3 7 FAN5702 — Configurable 180mA 6-LED Driver with I2C Control Typical Characteristics VIN = 3.6V, TA = 25°C, ILED = 20mA, and LED cathode terminals = 0.4V. Figure 4. Efficiency with LED Current of 8mA and 20mA Figure 5. LED Current Match for all 6 LED Channels at ILED=20mA. Figure 6. LED Current Variation vs. Temperature Figure 7. Shutdown Current vs. Input Voltage Figure 8. Switching Frequency over Temperature with LED Current at 20mA