- 您现在的位置：买卖IC网 > Sheet目录343 > MIC3263YML TR (Micrel Inc)IC LED DRIVER 6CH BKLT 24-MLF
Micrel, Inc.
MIC3263
Slope Compensation
The boost stage uses peak current m ode and requires
slope compensation. Slope comp ensation is required to
maintain internal stability of the boo st stage across all duty
cycles and to prevent any uns table oscillations. The
MIC3263 uses a combinatio n of internal slope
compensation and a additional slope compensation that is
set by an external resistor, RSLP . The ability to set the
proper slope compensation through the use of a single
external component results in design flexibility. This slope
compensation resistor, RSLP, can be calculated as
follows:
8.64 ×10 × V
Figure 11. Boost Stage
The operating duty cycle can be calculated using the
RSLP =
V OUT(MAX) - L ×F s w
-6
IN(MIN)
equation provided below:
where V IN(MAX) and V OUT(MAX) can be selected to system
speci ficatio ns. The lowest value of RSLP should be 15k ? .
D=
(V OUT - eff × V IN )
V OUT
and D ′ = 1 ? D
Ca lculate RSLP using th e lowest V IN and maximum V OUT
the system will operate.
V IN ×D
RSLP =
= 96.5k ?
8.64 ×10 ×12V
Find L using the following equation:
L=
I L_PP ×F sw
I L_PP is the inductor peak-to-peak ripple current.
Use a I L_PP of 20% to 40% of the total load current. F SW is
the boost switching frequency.
Outp ut Capacitor
In a boost converter, to find the C OUT for a given V OUT
ripple use the following calculation:
Example: For these operating conditions:
V IN(MIN) = 12V, V OUT(MAX) = 3 2V, L = 22 μ H,
F SW = 1MHz
32V - 22 μ H×1Mhz
-6
Use the next highest standard value.
Table 3 compiles and lists RSLP values for one set of
operating conditions. Select RSLP for V IN_MIN and V O_MAX .
C OUT =
I LED total ×D
V RIPPLE × F sw
V RIPPLE can usually be kept below 50mV:
I LED_TOTAL = 6 × 30mA = 180mA
In the MIC3263, the LED current in each channel is
individually regulated by that channels current amplifier
(linear current regulator). These current regulators are fast
enough to follow the boost output voltage ripple and to
keep the LED ripple currents much lower than C OUT can
filter the output ripple voltage.
January 2010
19
M9999-012110
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
MIC3287-24YD6 TR
IC LED DRIVR WHITE BCKLGT TSOT-6
MIC3289-16YD6 TR
IC LED DRIVR WHITE BCKLGT TSOT-6
MIC3291-18YML TR
IC PWM WLED DVR 1.8V 1.2MHZ 8MLF
MIC4100YM
IC DRIVER MOSFET 100V CMOS 8SOIC
MIC4102YM
IC DRIVER MOSFET 100V TTL 8SOIC
MIC4103YM
IC MOSFET DRIVER 100V CMOS 8SOIC
MIC4124YME
IC MOSFET DRVR DUAL NONINV 8SOIC
MIC4128YMME
IC DRIVER MOSFET 1.5A DUAL 8MSOP
相关代理商/技术参数
MIC3263YML-TR
功能描述:LED 驱动器 IC 6 输出 DC DC 稳压器 升压（升压） PWM 调光 30mA 24-MLF?（4x4） 制造商:microchip technology 系列:- 包装:剪切带（CT） 零件状态:停产 类型:DC DC 稳压器 拓扑:升压（升压） 内部开关:是 输出数:6 电压 - 供电（最低）:6V 电压 -?供电（最高）:40V 电压 - 输出:- 电流 - 输出/通道:30mA 频率:1.2MHz 调光:PWM 应用:背光 工作温度:-40°C ~ 125°C （TJ） 安装类型:表面贴装 封装/外壳:24-VFQFN 裸露焊盘，24-MLF? 供应商器件封装:24-MLF?（4x4） 标准包装:1
MIC3287
制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:1.2MHz PWM White LED Driver with OVP in Thin SOT-23 and 2mm x 2mm MFL
MIC3287_10
制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:1.2MHz PWM White LED Driver with OVP in Thin SOT-23 and 2mm x 2mm MFL
MIC3287-24YD6
制造商:Rochester Electronics LLC 功能描述: 制造商:RF Micro Devices Inc 功能描述:
MIC3287-24YD6 TR
功能描述:LED照明驱动器 2x2mm White LED Driver w/ 24V OVP (Lead Free)
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
MIC3287-24YD6TR
制造商:RF Micro Devices Inc 功能描述:
MIC3287-24YD6-TR
功能描述:LED 驱动器 IC 1 输出 DC DC 稳压器 升压（升压） 模拟，PWM 调光 350mA（开关） TSOT-23-6 制造商:microchip technology 系列:- 包装:剪切带（CT） 零件状态:停产 类型:DC DC 稳压器 拓扑:升压（升压） 内部开关:是 输出数:1 电压 - 供电（最低）:2.8V 电压 -?供电（最高）:6.5V 电压 - 输出:36V 电流 - 输出/通道:350mA（开关） 频率:1.2MHz 调光:模拟，PWM 应用:背光 工作温度:-40°C ~ 125°C （TJ） 安装类型:表面贴装 封装/外壳:SOT-23-6 细型，TSOT-23-6 供应商器件封装:TSOT-23-6 标准包装:1
MIC3287-24YML
制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:1.2MHz PWM White LED Driver with OVP in Thin SOT-23 and 2mm x 2mm MFL