SKYWORKS SKY81453-13-001

The SKY81453-13 is a highly integrated, high efficiency LED backlight solution for tablets, notebook computers, monitors, and other portable devices. An integrated boost converter provides a high voltage output for driving up to 28 LEDs. Six precision current sinks are programmable up to 60 mA per string. The integrated boost regulator switching frequency is adjustable from 600 kHz to 2 MHz for system integration flexibility, to optimize efficiency, and to minimize external passive component requirements. The SKY81453-13 supports filtered Pulse Width Modulation (PWM) dimming and I²C dimming. The duty cycle of PWM input signal and the I²C brightness control program can be used to control the LED current level not to exceed the maximum LED current, which is set by an external RISET resistor. The I²C brightness control and the PWM duty input signal are multiplied to control the output current level. When the PWM pin is not used, pull this pin to high or set the “ignore PWM input” bit (IGPW). For system protection, the SKY81453-13 senses open or shorted LED conditions and over-temperature events. High voltage current sink design prevents damage resulting from short LEDs. System faults are reported through the I²C interface. The SKY81453-13 is available in a Pb-free, 2.44 mm×2.44 mm 25-bump Wafer Level Chip Scale Package (WLCSP).

• VIN range: 2.5 V to 5.5 V
• Integrated 28 V boost converter
• Up to 93% efficiency
• Minimum off time: 50 ns
• Six current channels, 60 mA per channel
• Adjustable switching frequency: 600 kHz to 2 MHz
• Boost current limit selection
• Accuracy/matching: ±1.5% at 25 °C, 30 mA
• Fade in/out feature for brightness control
• I2C control
• Individual channel enable/disable, fault trigger point, and status programming
• 8-bit/256 programmable analog dimming
• PWM input frequency range: 1.5 kHz to 50 kHz
• Fault protection:
  • Independent channel shutdown for: open LED(s), shorted LED(s)
  • Boost over-voltage and over-current protection
  • Over-temperature shutdown
• WLCSP (25-bump, 2.44 mm×2.44 mm) (MSL1, 260 °C per JEDEC-J-STD-020)

• Tablet PCs
• Notebook computers
• Monitors
• Portable TV/DVD players