收藏本站
Integrated High-Voltage LED Driver
with Analog and PWM Dimming Control
High-Side Current-Sense Output (CS_OUT)
A high-side transconductance amplifier converts the
voltage across the LED current-sense resistor (R CS )
into an internal current output. This current flows
through an internal resistor connected to AGND. The
voltage gain for the LED current-sense signal is 4. The
amplified signal is then buffered and connected
through an internal switch to CS_OUT.
Internal Error Amplifier
The MAX16812 includes a built-in voltage-error amplifi-
er, which can be used to close the feedback loop. The
internal LED current-sense output signal is buffered
internally and then connected to CS_OUT through an
internal switch. CS_OUT is connected to the inverting
input (FB) pin of the error amplifier through a resistor.
See Figures 4 and 5. The reference voltage for the out-
put current is connected to REFI, the noninverting input
of the error amplifier. When the internal dimming signal
is low, COMP is disconnected from the output of the
error amplifier and CS_OUT is simultaneously discon-
nected from the buffered LED current-sense output sig-
nal (Figure 5). When the internal dimming signal is high,
the output of the op amp is connected to COMP and
CS_OUT is connected to the buffered LED current-
sense signal at the same time (Figure 4). This enables
the compensation capacitor to hold the charge when
the DIM signal has turned off the internal switching
MOSFET gate drive. To maintain the charge on the
compensation capacitors C COMP1 and C COMP2 , the
capacitors should be of the low-leakage ceramic type.
When the internal dimming signal is enabled, the voltage
on the compensation capacitor forces the converter into
steady state almost instantaneously. The voltage on
COMP is subtracted from the internal slope compensa-
tion signal and is then connected to one of the inputs of
the PWM comparator. The PWM comparator input is of
the CMOS type with very low bias currents.
C COMP2
X1
STATE A
OUT
R COMP1
R COMP2
EA
C COMP1
COMP
REFI
Figure 4. Internal Error Amplifier Connection (Dimming Signal High)
C COMP2
X1
STATE B
OUT
R COMP1
R COMP2
EA
C COMP1
COMP
REFI
Figure 5. Internal Error Amplifier Connections (Dimming Signal Low)
______________________________________________________________________________________
11
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
MAX16814AUP+T IC LED DVR HI-BRIGHT 4CH 20TSSOP
MAX16821CATI+T IC LED DRIVR HIGH BRIGHT 28-TQFN
MAX16822AASA/V+ IC LED DRIVER HIGH BRIGHT 8SOIC
MAX16826ATJ+C24 IC LED DVR HB PROGR 32-HQFN
MAX16835ATE+T IC LED DRIVR HIGH BRIGHT 16-TQFN
MAX16838AUP+ IC LED DRIVR HIGH BRIGHT 20TSSOP
MAX1698EUB IC LED DRVR WT/CLR BCKLGT 10MSOP
MAX17014EVKIT+ KIT EVAL FOR MAX17014
相关代理商/技术参数
MAX16812ATI/V+T 功能描述:LED照明驱动器 w/Analog & PWM Dimming Control 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
MAX16812ATI+ 功能描述:LED照明驱动器 w/Analog & PWM Dimming Control 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
MAX16812ATI+T 功能描述:LED照明驱动器 w/Analog & PWM Dimming Control 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
MAX16812EVKIT+ 功能描述:LED 照明开发工具 Evaluation Kit for the MAX16812 RoHS:否 制造商:Fairchild Semiconductor 产品:Evaluation Kits 用于:FL7732 核心: 电源电压:120V 系列: 封装:
MAX16813ATP/V+ 制造商:Maxim Integrated Products 功能描述:IC LED DVR 4CH CTLR/DISC QFN
MAX16813ATP/V+T 功能描述:LED照明驱动器 Integrated 4Ch HB LED Driver RoHS:否 制造商:Maxim Integrated 输入电压: 工作频率: 最大电源电流: 输出电流: 最大工作温度: 安装风格: 封装 / 箱体:
MAX16813ATP+ 制造商:Maxim Integrated Products 功能描述:IC LED DVR 4CH CTLR/DISC QFN
MAX16813ATP+T 功能描述:LED照明驱动器 Integrated 4Ch HB LED Driver RoHS:否 制造商:Maxim Integrated 输入电压: 工作频率: 最大电源电流: 输出电流: 最大工作温度: 安装风格: 封装 / 箱体: