收藏本站
Micrel, Inc.
Functional Diagram
MIC2289C
VIN
FB
EN
OUT
OVP
SW
V REF
95mV
g m
PWM
Generator
S
1.2MHz
Oscillator
Ramp
Generator
GND
MIC2289C Block Diagram
I LED =
Functional Description
The MIC2289C is a constant frequency, PWM current
mode boost regulator. The block diagram is shown
above. The MIC2289C is composed of an oscillator,
slope compensation ramp generator, current ampli ? er,
gm error ampli ? er, PWM generator, 500mA bipolar
output transistor, and Schottky recti ? er diode. The
oscillator generates a 1.2MHz clock. The clock’s two
functions are to trigger the PWM generator that turns on
the output transistor and to reset the slope
compensation ramp generator. The current ampli ? er is
used to measure the switch current by amplifying the
voltage signal from the internal sense resistor. The
output of the current ampli ? er is summed with the output
of the slope compensation ramp generator. This
summed current-loop signal is fed to one of the inputs of
the PWM generator.
The gm error ampli ? er measures the LED current
through the external sense resistor and ampli ? es the
error between the detected signal and the 95mV
reference voltage. The output of the gm error ampli ? er
provides the voltage-loop signal that is fed to the other
input of the PWM generator. When the current-loop
signal exceeds the voltage-loop signal, the PWM
generator turns off the bipolar output transistor. The next
clock period initiates the next switching cycle,
maintaining the constant frequency current-mode PWM
control. The LED is set by the feedback resistor:
95mW
R FB
The Enable pin shuts down the output switching and
disables control circuitry to reduce input current-to-
leakage levels. Enable pin input current is zero at zero
volts.
August 2007
5
M9999-081507-B
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
MIC2291YD5 TR IC LED DRIVER PHOTO FLASH TSOT-5
MIC2293-15YML TR IC LED DRIVER WHITE BCKLGT 8-MLF
MIC2293C-34YML TR IC LED DRIVER WHITE BCKLGT 8-MLF
MIC2297-42YML TR IC LED DRIVR WHITE BCKLGT 10-MLF
MIC2298-15YML TR IC LED DRIVER HIGH BRIGHT 12-MLF
MIC2299-15YML TR IC LED DRIVR WHITE BCKLGT 12-MLF
MIC26603YJL EV BOARD EVAL FOR MIC26603YJL
MIC26901YJL EV BOARD EVAL FOR MIC26901YJL
相关代理商/技术参数
MIC2289C-34YML 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:White LED Driver Internal Schottky Diode and OVP
MIC2289CBD5 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:White LED Driver Internal Schottky Diode and OVP
MIC2289CYD5 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:White LED Driver Internal Schottky Diode and OVP
MIC2290 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:2mm 】 2mm PWM Boost Regulator with Internal Schotty Diode
MIC2290_07 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:2mm 】 2mm PWM Boost Regulator with Internal Schotty Diode
MIC2290BML 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:2mm 】 2mm PWM Boost Regulator with Internal Schotty Diode
MIC2290BML TR 功能描述:IC REG BOOST ADJ 0.5A 8MLF RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:20 系列:SIMPLE SWITCHER® 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:12V 输入电压:4 V ~ 60 V PWM 型:电压模式 频率 - 开关:52kHz 电流 - 输出:1A 同步整流器:无 工作温度:-40°C ~ 125°C 安装类型:通孔 封装/外壳:16-DIP（0.300"，7.62mm） 包装:管件 供应商设备封装:16-DIP 其它名称:*LM2575HVN-12LM2575HVN-12
MIC2290YML 制造商:MICREL 制造商全称:Micrel Semiconductor 功能描述:2mm 】 2mm PWM Boost Regulator with Internal Schotty Diode