MAX8647:Ultra-Efficient Charge Pumps for Six White/RGB LEDs in 3mm x 3mm Thin QFN

Achieves Industry's Highest Efficiency Using the Industry's First Negative Charge Pump Driving Six White/RGB LEDs Independently

The MAX8647/MAX8648 drive up to six white LEDs or two sets of RGB LEDs with regulated constant current for display backlight and fun light applications. By utilizing an inverting charge pump and extremely low-dropout adaptive current regulators, these ICs achieve very high efficiency over the full 1-cell Li+ battery voltage range and even with large LED forward voltage mismatch. The 1MHz fixed-frequency switching allows for tiny external components. The regulation scheme is optimized to ensure low EMI and low input ripple. The MAX8647/MAX8648 include thermal shutdown, open- and short-circuit protection. The MAX8647 features an I²C serial port, while the MAX8648 features a three-wire serial-pulse logic interface. Both devices support independent on/off and dimming for main and subbacklights. The dimming ranges are pseudo-logarithmic from 24mA to 0.1mA and off in 32 steps. Both devices include a temperature derating function to safely allow bright 24mA full-scale output current setting while automatically reducing current to protect LEDs at high ambient temperatures above +60°C. The MAX8647/MAX8648 are available in a 16-pin, 3mm x 3mm thin QFN package (0.8mm max height).

Key Features
  • Six Adaptive Current Regulators
  • Independent Voltage Supply for Each LED
  • Individual LED Brightness Control (MAX8647)
  • 24mA to 0.1mA Dimming Range
    • I²C Interface (MAX8647)
    • Serial-Pulse Dimming Logic (MAX8648)
  • ±2% Accuracy, ±0.4% Matching (typ)
  • Low 70µA Quiescent Current
  • Low 1µA Shutdown Current
  • Inrush Current Limit
  • TA Derating Function Protects LEDs
  • 16-Pin, 3mm x 3mm Thin QFN Package
MAX8647, MAX8648: Typical Operating Circuit
MAX8647, MAX8648: Typical Operating Circuit
Applications/Uses
  • Camera Flash or RGB Indicators
  • Cellular Phones and Smartphones
  • PDAs, Digital Cameras, and Camcorders
  • White LED Backlighting, Single or Dual Display
  • Wide-Gamut RGB LED Display Backlighting
DataSheet
titleDownload file
MAX8647-MAX8648 Data SheetMAX8647-MAX8648.pdf
Parametrics
Part NumberBattery InputRegulation TopologyMax. No. of LEDsLED ChannelsLED ConfigurationILED per Channel
(A)
Dimming RatioDimming ControlPOUT
(W)
VIN
(V)
VIN
(V)
ICC
(mA)
LED String Volt.
(V)
Oper. Freq.
(kHz)
Package/PinsBudgetary
Price
maxmaxminmaxmaxmaxSee Notes
MAX86471-Cell Li+Charge Pump66Parallel0.024240I2C Serial0.62.75.50.151000TQFN/16$2.17 @1k
MAX8648Serial Pulse0.2TQFN/16$1.89 @1k
Design kits & evaluation modules
Quality and Environmental Data
Related Products
  • MAX8595:High-Efficiency, 36V Step-Up Converters with TA Derating Option for 2 to 9 White LEDs
  • MAX8596:High-Efficiency, 36V Step-Up Converters with TA Derating Option for 2 to 9 White LEDs
  • MAX1578:Complete Bias and White LED Power Supplies for Small TFT Displays
  • MAX1576:480mA White LED 1x/1.5x/2x Charge Pump for Backlighting and Camera Flash
  • MAX1574:180mA, 1x/2x, White LED Charge Pump in 3mm x 3mm TDFN
  • MAX1575:White LED 1x/1.5x Charge Pump for Main and Sub-Displays
  • MAX1573:White LED 1x/1.5x Charge Pump in UCSP and Thin QFN
  • MAX1582:High-Efficiency Step-Up Converters for White LED Main and Subdisplay Backlighting
  • MAX1561:High-Efficiency, 26V Step-Up Converters for Two to Six White LEDs
  • MAX1599:High-Efficiency, 26V Step-Up Converters for Two to Six White LEDs
  • MAX1848:White LED Step-Up Converter in SOT23
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX8647ETE+ActiveTQFN,;16 pin;9.6 mm²-40°C to +85°CLead Free
MAX8647ETE+TActiveTQFN,;16 pin;9.6 mm²-40°C to +85°CLead Free
MAX8647-MAX8648.pdf MAX8648
MAX8647.pdf MAX8647
MAX8647-MAX8648.pdf MAX8648