收藏本站
APPLICATIONS INFORMATION
V OUT = 0.8(1 + 1 )
Overcurrent Protection
Over current protection on the SP6123 is imple-
mented through detection of an excess voltage
condition across the high side switch during
conduction. This is typically referred to as high
side R DS(ON) detection. By using the R DS(ON) of
Q1 to measure the output current, the current
limit circuit eliminates the sense resistor that
would otherwise be required and the corre-
sponding loss associated with it. This improves
the overall efficiency and reduces the number of
components in the power path benefiting size
and cost. R DS(ON) sensing is by default inaccu-
rate and is primarily meant to protect the power
supply during a fault condition. The overcurrent
trip point will vary from unit to unit as the
R DS(ON) of MOSFET varies. The SP6123 pro-
vides a built-in 200mV threshold between the
V CC and SWN pins.
Output Voltage Program
As shown in Figure 5, the voltage divider con-
necting to the V FB pin programs the output
voltage according to
R
R 2
where 0.8V is the internal reference voltage.
Select R2 in the range of 10k to 100k, and R1 can
be calculated using
R 1 = R 2 (V OUT – 0.8)
0.8
V OUT
The overcurrent threshold can be calculated as
I MAX = 200mV
R DS(ON)
To ensure accurate current sensing, the V CC pin
should be connected directly to the drain of the
high side MOSFET. A RC filter on the V CC pin
is not recommended because it would artifi-
?
SP6123
V FB
R1
R2
cially alter the current signal and reduce the
overcurrent threshold from the value given by
the equation.
Figure 5. A voltage divider connected to the V FB pin
programs the output voltage.
Date: 9/13/04
SP6123 Low Voltage, Synchronous Step Down PWM Controller
15
? Copyright 2004 Sipex Corporation
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
MAX4825ETP+T IC RELAY DRIVER 8CHAN 20-TQFN
MAX4822ETP+T IC RELAY DRIVER 8CHAN 20-TQFN
R1S8-1505/P-R CONV DC/DC 1W 15VIN 05VOUT
SP6121EB EVAL BOARD FOR SP6121
A9CCA-0408F FLEX CABLE - AFG04A/AF04/AFG04A
R1S-2409/P-R CONV DC/DC 1W 24VIN 09VOUT
SP6120EB EVAL BOARD FOR SP6120
ASPI-6045S-330M-T INDUCTOR POWER 33UH 6045 SMD
相关代理商/技术参数
SP6123EN-L 制造商:Exar Corporation 功能描述:IC BUCK CONTROLLER LOW VOLT 300KHZ
SP6125 制造商:SIPEX 制造商全称:Sipex Corporation 功能描述:High-Voltage, Step Down Controller in TSOT6
SP6125EB 功能描述:电源管理IC开发工具 Eval Board for SP6125 Series RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
SP6125EK1L 制造商:SIPEX 制造商全称:Sipex Corporation 功能描述:High-Voltage, Step Down Controller in TSOT6
SP6125EK1-L 功能描述:DC/DC 开关控制器 RoHS:否 制造商:Texas Instruments 输入电压:6 V to 100 V 开关频率: 输出电压:1.215 V to 80 V 输出电流:3.5 A 输出端数量:1 最大工作温度:+ 125 C 安装风格: 封装 / 箱体:CPAK
SP6125EK1-L/TR 功能描述:电源管理IC开发工具 High-Voltage Step Down Controller RoHS:否 制造商:Maxim Integrated 产品:Evaluation Kits 类型:Battery Management 工具用于评估:MAX17710GB 输入电压: 输出电压:1.8 V
SP6125EK1L/TR1 制造商:SIPEX 制造商全称:Sipex Corporation 功能描述:High-Voltage, Step Down Controller in TSOT6
SP6126 制造商:SIPEX 制造商全称:Sipex Corporation 功能描述:Evaluation Board Manual