参数资料
型号: LTC3803IS6-5
厂商: LINEAR TECHNOLOGY CORP
元件分类: 稳压器
英文描述: 1 A SWITCHING CONTROLLER, 230 kHz SWITCHING FREQ-MAX, PDSO6
封装: 1 MM HEIGHT, PLASTIC, MO-193, TSOT-23, 6 PIN
文件页数: 2/16页
文件大小: 162K
代理商: LTC3803IS6-5
LTC3803-5
10
38035fd
Leakage Inductance
Transformer leakage inductance (on either the primary
or secondary) causes a voltage spike to occur after the
output switch (Q1) turn-off. This is increasingly prominent
at higher load currents, where more stored energy must
be dissipated. In some cases a “snubber” circuit will be
required to avoid overvoltage breakdown at the MOSFET’s
drain node. Application Note 19 is a good reference on
snubber design.
A bilar or similar winding technique is a good way to
minimize troublesome leakage inductances. However,
remember that this will limit the primary-to-secondary
breakdown voltage, so bilar winding is not always
practical.
CURRENT SENSE RESISTOR CONSIDERATIONS
The external current sense resistor (RSENSE in Figure 2)
allows the user to optimize the current limit behavior for
the particular application. As the current sense resistor
is varied from several ohms down to tens of milliohms,
peak switch current goes from a fraction of an ampere to
several amperes. Care must be taken to ensure proper
circuit operation, especially with small current sense
resistor values.
For example, a peak switch current of 5A requires a sense
resistor of 0.020Ω. Note that the instantaneous peak power
in the sense resistor is 0.5W and it must be rated accord-
ingly. The LTC3803-5 has only a single sense line to this
resistor. Therefore, any parasitic resistance in the ground
side connection of the sense resistor will increase its ap-
parent value. In the case of a 0.020Ω sense resistor,
one
milliohm of parasitic resistance will cause a 5% reduction
in peak switch current. So the resistance of printed circuit
copper traces and vias cannot necessarily be ignored.
PROGRAMMABLE SLOPE COMPENSATION
The LTC3803-5 injects a ramping current through its SENSE
pin into an external slope compensation resistor (RSL in
Figure 2). This current ramp starts at zero right after the
NGATE pin has been high for the LTC3803-5’s minimum
duty cycle of 6.5%. The current rises linearly towards a
peak of 5μA at the maximum duty cycle of 80%, shutting
off once the NGATE pin goes low. A series resistor (RSL)
connecting the SENSE pin to the current sense resistor
(RSENSE) thus develops a ramping voltage drop. From
the perspective of the SENSE pin, this ramping voltage
adds to the voltage across the sense resistor, effectively
reducing the current comparator threshold in proportion
APPLICATIONS INFORMATION
相关PDF资料
PDF描述
LTC3805HMSE-5#TRMPBF SWITCHING CONTROLLER, 700 kHz SWITCHING FREQ-MAX, PDSO10
LTC3805EDD-5#TRMPBF SWITCHING CONTROLLER, 700 kHz SWITCHING FREQ-MAX, PDSO10
LTC3805IMSE-5#TRMPBF SWITCHING CONTROLLER, 700 kHz SWITCHING FREQ-MAX, PDSO10
LTC3808EDE SWITCHING CONTROLLER, PDSO8
LTC3808EGN SWITCHING CONTROLLER, PDSO8
相关代理商/技术参数
参数描述
LTC3803IS6-5#PBF 制造商:Linear Technology 功能描述:DC DC Cntrlr Single-OUT Sync Flyback 5V Input 6-Pin TSOT-23 制造商:Linear Technology 功能描述:DC DC Cntrlr Single-OUT Sync Flyback 5V Input 6-Pin TSOT-23 Bulk
LTC3803IS6-5#TRMPBF 功能描述:IC REG CTRLR FLYBK PWM TSOT23-6 RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR)
LTC3803IS6-5#TRPBF 功能描述:IC REG CTRLR FLYBK PWM TSOT23-6 RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR)
LTC3803IS6TRMPBF 制造商:Linear Technology 功能描述:DC-DC Controller Flyback 75V TSOT23-6
LTC3803MPS6#TRMPBF 功能描述:IC REG CTRLR FLYBK PWM TSOT23-6 RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 特色产品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 标准包装:1 系列:PowerWise® PWM 型:电压模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.5 V ~ 18 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-5°C ~ 125°C 封装/外壳:32-WFQFN 裸露焊盘 包装:Digi-Reel® 产品目录页面:1303 (CN2011-ZH PDF) 其它名称:LM3754SQDKR