White LED Step-Up Converter in SOT23

Current Regulated Step-Up Converter Powers White LEDs with Uniform Brightness

Please check latest availability status for a specific part variant.


The MAX1848 drives white LEDs with a constant current to provide backlight in cell phones, PDAs, and other hand-held devices. The step-up converter topology allows series connection of the white LEDs so that the LED currents are identical for uniform brightness. This configuration eliminates the need for ballast resistors and expensive factory calibration. Other benefits include greater simplicity, lower cost, higher efficiency, and greater reliability.

This step-up PWM converter includes an internal, high-voltage, low RDSON N-channel MOSFET switch for high efficiency and maximum battery life. A single analog voltage Dual Mode™ input provides a simple means of brightness adjustment and on/off control. Fast 1.2MHz current-mode PWM control allows for small input and output capacitors and a small inductor while minimizing ripple on the input supply/battery. Programmable soft-start eliminates inrush current during startup.

The MAX1848 is available in space-saving 8-pin thin QFN (3mm x 3mm) and 8-pin SOT23 packages.
MAX1848: Typical Application Circuit MAX1848: Typical Application Circuit Enlarge+

Key Features

  • Constant Current Regulation for Uniform Illumination
  • High 87% Efficiency
  • Analog or Logic Control of LED Intensity
  • 0.8W Output Power with Internal High-Voltage MOSFET Switch
  • Small, Low-Profile External Components
  • 2.6V to 5.5V Input Range
  • 13V Maximum Output with Overvoltage Protection
  • Optimized for Low Input Ripple
  • Programmable Soft-Start
  • 0.3µA Shutdown Current
  • Small 8-pin Thin QFN (3mm x 3mm) and 8-Pin SOT23 Packages


  • Cell Phones/Smartphones
  • e-Books and Subnotebooks
  • PDAs, Palmtops, and Wireless Handhelds
  • White LED Display Backlighting
Part NumberBattery InputRegulation TopologyMax. No. of LEDsLED ChannelsLED ConfigurationILED per Channel
Dimming RatioDimming ControlVCURR_SENSE
LED String Volt.
Oper. Freq.
maxmaxminmaxmaxmaxSee Notes
MAX1848 1-Cell Li+Inductor Based61Series0.0620Analog750.82.65.52121200
$1.39 @1k
See All LED Drivers (78)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

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