- 您现在的位置：买卖IC网 > Datasheet目录310 > AL8807W5-7 (Diodes Inc)IC LED DRVR DCDC BUCK SOT25 Datasheet资料下载
参数资料
| 型号： | AL8807W5-7 |
| 厂商： | Diodes Inc |
| 文件页数： | 9/20页 |
| 文件大小： | 0K |
| 描述： | IC LED DRVR DCDC BUCK SOT25 |
| 标准包装： | 1 |
| 恒定电流： | 是 |
| 拓扑： | PWM，降压（降压） |
| 输出数： | 1 |
| 内部驱动器： | 是 |
| 类型 - 主要： | 通用 |
| 类型 - 次要： | 白色 LED |
| 频率： | 1MHz |
| 电源电压： | 6 V ~ 36 V |
| 输出电压： | 36V |
| 安装类型： | 表面贴装 |
| 封装/外壳： | SC-74A，SOT-753 |
| 供应商设备封装： | SOT-25 |
| 包装： | 标准包装 |
| 工作温度： | -40°C ~ 125°C |
| 其它名称： | AL8807W5-7DIDKR |
AL8807
Application Information
The AL8807 is a hysteretic (also known as equal ripple) LED driver with integrated power switch. It is available in two packages that provide a PCB
area-power dissipation capability compromise. It is recommended that at higher LED currents/smaller PCBs that the MSOP-8EP version is used to
maximize the allowable LED current over a wider ambient temperature range.
AL8807 Operation
In normal operation, when voltage is applied at +V IN , the AL8807 internal switch is turned on. Current starts to flow through sense resistor R 1 ,
inductor L1, and the LEDs. The current ramps up linearly, and the ramp rate is determined by the input voltage +Vin and the inductor L1.
This rising current produces a voltage ramp across R 1 . The internal circuit of the AL8807 senses the voltage across R 1 and applies a proportional
voltage to the input of the internal comparator.
When this voltage reaches an internally set upper threshold, the internal switch is turned off. The inductor current continues to flow through R 1 , L1,
the LEDs and the schottky diode D1, and back to the supply rail, but it decays, with the rate of decay determined by the forward voltage drop of the
LEDs and the schottky diode.
This decaying current produces a falling voltage at R 1 , which is sensed by the AL8807. A voltage proportional to the sense voltage across R 1 is
applied at the input of the internal comparator. When this voltage falls to the internally set lower threshold, the internal switch is turned on again.
This switch-on-and-off cycle continues to provide the average LED current set by the sense resistor R 1 .
LED Current Control
The LED current is controlled by the resistor R1 in Figure 30.
Figure 30 Typical Application Circuit
Connected between V IN and SET the nominal average output current in the LED(s) is defined as:
I LED ?
V THD
R 1
For example for a desired LED current of 660mA and a default voltage V CTRL =2.5V the resulting resistor is:
? ? 150 m ?
R 1 ?
V THD
I LED
0 . 1
0 . 66
DC Dimming
Further control of the LED current can be achieved by driving the CTRL pin with an external voltage (between 0.4V and 2.5V); the average LED
current becomes:
I LED ?
V CTRL V THD
V REF R SET
be clamped to approximately 100% and follows I LED ? THD .
With 0.5V ≤ V CTRL ≤ 2.5V the LED current varies linearly with V CTRL , as in figure 2. If the CTRL pin is brought higher than 2.5V, the LED current will
V
R SET
When the CTRL voltage falls below the threshold, 0.4V, the output switch is turned off which allows PWM dimming.
AL8807
Document number: DS35281 Rev. 5 - 2
9 of 20
www.diodes.com
March 2013
? Diodes Incorporated
相关PDF资料 |
PDF描述 |
|---|---|
| AL9910AS-13 | IC LED DRVR HIGH BRIGHT SO8EP |
| ALC60481R05 | PWR SUP AC-DC 6-48V 1.05A 50.4W |
| ALV100362R5 | POWER SUPPLY AC-DC 36V 2.5A 90W |
| ALV60361R7 | POWER SUPPLY AC-DC 36V 1.7A 61W |
| ALV80126R5 | POWER SUPPLY AC-DC 12V 6.5A 78W |
相关代理商/技术参数 |
参数描述 |
|---|---|
| AL8808EV1 | 功能描述:AL8808 1, Non-Isolated Output LED Driver Evaluation Board 制造商:diodes incorporated 系列:- 零件状态:有效 电流 - 输出/通道:680mA 输出和类型:1，非隔离 电压 - 输出:- 特性:可调光 电压 - 输入:6 V ~ 30 V 所含物品:板 使用的 IC/零件:AL8808 标准包装:1 |
| AL8808EV2 | 功能描述:AL8808 1, Non-Isolated Output LED Driver Evaluation Board 制造商:diodes incorporated 系列:- 零件状态:有效 电流 - 输出/通道:680mA 输出和类型:1，非隔离 电压 - 输出:- 特性:- 电压 - 输入:12VAC，12 V ~ 20 V 所含物品:板 使用的 IC/零件:AL8808 标准包装:1 |
| AL8808WT-7 | 功能描述:LED照明驱动器 LED MV Int Switch TS Switch TSOT25 T&R 3K RoHS:否 制造商:STMicroelectronics 输入电压:11.5 V to 23 V 工作频率: 最大电源电流:1.7 mA 输出电流: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:SO-16N |
| AL8811 | 制造商:DIODES 制造商全称:Diodes Incorporated 功能描述:Boost/Buck/Inverting DC-DC CONVERTER |
| AL8811M8-13 | 制造商:Diodes Incorporated 功能描述:LED LV INT SWITCH MSOP-8 T&R 2.5K - Tape and Reel 制造商:Diodes Incorporated 功能描述:LED MV INT SWITCH MSOP-8 |
发布紧急采购，3分钟左右您将得到回复。