谁有白光LED驱动电路，最好是1。5V的，驱动4-5只发光管，最好是散件组装，因集成电路太难找，当然也可参考，谢谢。Emall:xiajiliang2000@yahoo.com.cn

AAT3113在输入电压在2.7-5.5V的范围之间可驱动4－6颗白光LED，每个LED的通过最大电流是20mA，外部仅需要4颗电容。
需要的话可与我联系 pride_chen@hotmail.com 

推荐AMC7100 SeriesAMC7100/01/02/10/11/12  White/Blue LED Driver for Li-Ion Battery Application SOT26 MSOP8
Description                                                                      Data Sheet Download:  
        AMC7100/01/02/10/11/12 are member of ADDM's North Star White/Blue LED driver family. No external component was required. Especially good for use Li-ion battery direct driving LCD display's backlight white LEDs. Since no Boost converter or charge pump inside, the efficiency could reach 93% and no switching noise. Integrated 16-step programmable output sink current control circuit that could programming LED's current (brightness) (AMC7100/1/2). Target end application are color LCD display mobile phone with color display, smart phone, PDA, etc.  
Features  
⊕No external component required. Integrated current sense resistors.
⊕Programmable output current control, programming range 33% to 100% in 16 steps for LED Dimming control (AMC7100/1/2).  
⊕Pre-setted maximum output current 20 mA.
⊕Individual current sink circuit for all LEDs outputs to prevent short / open circuit on LEDs.  
⊕3 channels (SOT-26), 4 channels (TSSOP-8), 6 channels (MSOP-10) available.

⊕> 90% efficiency
⊕Supply voltage range 2.7V ~ 6V  
⊕0.2uA standby current
⊕ESD protection HBM 2KV

Applications
⊕Small Size Color LCD Backlights
⊕Mobile Phone, Smart Phone Keypad Backlights.

LM2623LM2623
General Purpose, Gated Oscillator Based, DC/DC Boost
Converter
General Description
The LM2623 is a high efficiency, general purpose, step-up
DC-DC switching regulator for battery-powered and low input
voltage systems. It accepts an input voltage between .8
and 14 volts and converts it into a regulated output voltage
between 1.24 and 14 volts. Efficiencies up to 90% are
achievable with the LM2623.
In order to adapt to a number of applications, the LM2623
allows the designer to vary the output voltage, the operating
frequency (300kHz to 2 MHz) and duty cycle (17% to 90%)
to optimize the part’s performance. The selected values CAN
be fixed or CAN vary with battery voltage or input to output
voltage ratio. The LM2623 uses a very simple, on/off regulation
mode to produce good efficiency and stable operation
over a wide operating range. It normally regulates by skipping
switching cycles when it reaches the regulation limit
(Pulse Frequency Modulation).
Note: Please read the "Non-Linear Effect" and "Choosing
The Correct C3 Capacitor" sub-sections of the Design Procedure
section of this data sheet, so that any challenges with
designing with this part CAN be taken into account before a
board design/layout is finalized.
For Alternative Solutions, See Also: LM2700, LM2622,
LM2731, LM2733, and LM2621.
Features
Good Efficiency Over a Very Wide Load Range
Very Low Output Voltage Ripple
Small, Mini-SO-8 Package (Half the Footprint of
Standard 8 pin SO Package)
1.09 mm Package Height
Up to 2 MHz Switching Frequency
0.8V to 14V Operating Voltage
1.1V Start-up Voltage
1.24V - 14V Adjustable Output Voltage
Up to 2A Load Current at low Output Voltages
0.17Ω Internal MOSFET
Up to 90% Regulator Efficiency
80 µA TyPICal Operating Current (into VDD pin of supply)
<2.5&micro;A Guaranteed Supply Current In Shutdown
4mm x 4mm Thermally Enhanced LLP Package Option

对不起，我要1.5V的。如3V以上很好解决。