AP5726
WHITE LED STEP-UP CONVERTER
Applications Information
Inductor Selection
A 10 μ H~22 μ H inductor is recommended for most AP5726 applications. For high efficiency the inductor should
have low core losses at 1.2MHz and low DCR (copper wire resistance). The inductor saturation current rating
should also exceed the peak input current, especially for high load current applications (like 3S8P).
Capacitor Selection
The small size of ceramic capacitors are ideal for AP5726 applications. X5R and X7R types are recommended
because they retain their capacitance over wider voltage and temperature ranges than other types such as Y5V
or Z5U. A 1 μ F input capacitor and a 1 μ F output capacitor are sufficient for most AP5726 applications. For high
output current applications like 3S8P, larger output capacitor of 2.2uF ~ 4.7uF is recommended to minimize
output ripple.
Diode Selection
Schottky diodes, with their low forward voltage drop and fast reverse recovery, are the ideal choices for AP5726
applications. The forward voltage drop of a Schottky diode represents the conduction losses in the diode, while
the diode capacitance (C T or C D ) represents the switching losses. For diode selection, both forward voltage drop
and diode capacitance need to be considered. Schottky diodes with higher current ratings usually have lower
forward voltage drop and larger diode capacitance. Larger Schottky diode capacitance can cause significant
switching losses at the 1.2MHz switching frequency of the AP5726. A Schottky diode rated at 100mA to 200mA is
sufficient for most AP5726 applications.
LED Current Control
The LED current is controlled by the feedback resistor (R SET in Figure 1 ). The feedback reference is 0.31V. The
LED current is 0.31V/ R SET . In order to have accurate LED current, precision resistors are preferred (1% is
recommended). The formula and table for R SET selection are shown below.
R SET = 0.31V/I LED (See Table 1 )
Table 1. R SET Resistor Value Selection
I LED (mA)
R SET ( ? )
5 62
10 31
15 20.6
20 15.5
30 10.3
AP5726
Document number: DS31845 Rev. 3 - 2
9 of 17
www.diodes.com
July 2010
? Diodes Incorporated
相关PDF资料
AP8800AWT-7 IC LED DRIVER TSOT23-5
AP8800FNG-7 IC LED DRIVER HIGH BRIGHT 10DFN
AP8801M8G-13 IC LED DRIVER HIGH BRIGHT 8MSOP
AP8802HSP-13 IC LED DRIVER HIGH BRIGHT 8SOIC
AP8802SPG-13 IC LED DRIVER HIGH BRIGHT 8SOIC
AP8803WTG-7 IC LED DRIVER CONN CURR TSOT23-5
APEK4402KLP-01-T-DK BOARD EVAL FOR A4402
APP-001-15AMP PLUG AUTO PWR BLACK W/LED 15AMP
相关代理商/技术参数
AP5726WUG-7 功能描述:开关变换器、稳压器与控制器 WH LED STEP-UP DC/DC CONV 2-6 LED RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
AP5727 制造商:DIODES 制造商全称:Diodes Incorporated 功能描述:Boost converter for the bias voltage of small size OLED and LCD displays
AP5727_11 制造商:DIODES 制造商全称:Diodes Incorporated 功能描述:BIAS POWER SUPPLY FOR OLED SUB DISPLAY AND TFT-LED
AP5727WG-7 功能描述:开关变换器、稳压器与控制器 BIAS OLED PWR SUPPLY SUB TFT 1.2MHz RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
AP5808 功能描述:LCD 图形显示模块和配件 Rack Accessories Plastic Black RoHS:否 制造商:ELECTRONIC ASSEMBLY 产品: 分辨率:128 x 64 流体类型:FSTN Positive 接口: 背光: 背景色:White 工作温度范围:- 20 C to + 70 C 封装:Bulk
AP5816 功能描述:LCD 图形显示模块和配件 Rack Accessories Plastic Black RoHS:否 制造商:ELECTRONIC ASSEMBLY 产品: 分辨率:128 x 64 流体类型:FSTN Positive 接口: 背光: 背景色:White 工作温度范围:- 20 C to + 70 C 封装:Bulk
AP5821 功能描述:电缆组件 USB to VGA LCD Controller 1.83m BLK RoHS:否 制造商:Molex 产品:Power Assemblies 类型:Cable Assembly 连接器端口 A:No Connector 连接器端口 A 管脚计数:4 连接器端口 B:No Connector 连接器端口 B 管脚计数: 型式:Male 线规 - 美国线规(AWG):20, 28 长度:0.305 m 颜色:Black, Red
AP5822 功能描述:电缆组件 USB to VGA LCD Controller 3m BLK RoHS:否 制造商:Molex 产品:Power Assemblies 类型:Cable Assembly 连接器端口 A:No Connector 连接器端口 A 管脚计数:4 连接器端口 B:No Connector 连接器端口 B 管脚计数: 型式:Male 线规 - 美国线规(AWG):20, 28 长度:0.305 m 颜色:Black, Red