參數(shù)資料
型號(hào)： TPS40021PWP
廠商： TEXAS INSTRUMENTS INC
元件分類： 穩(wěn)壓器
英文描述： 0.01 A SWITCHING CONTROLLER, 1100 kHz SWITCHING FREQ-MAX, PDSO16
封裝： GREEN, PLASTIC, HTSSOP-16
文件頁(yè)數(shù)： 2/36頁(yè)
文件大小： 724K
代理商： TPS40021PWP
TPS40020
TPS40021
SLUS535D MARCH 2003 REVISED JULY 2007
www.ti.com
10
APPLICATION INFORMATION
Synchronous Rectification and Predictive Gate Delay
In a normal buck converter, when the highside switch turns off, current is flowing in the inductor. Since this
current cannot be stopped immediately a rectifier or catch device is used to give this current a path to flow and
maintain voltage levels at a safe level. This device can be a simple diode or it can be an activelycontrolled
transistor if a control signal is available to drive it. The TPS4002X provides a signal to drive an Nchannel
MOSFET as a synchronous rectifier. This control signal is carefully coordinated with the drive signal for the
main switch so that there is absolute minimum deadtime between the turn off of one FET and the turn on of
the other. This TIpatented function, predictive gate delay, uses information from the current switching cycle
to adjust the delays for the next cycle virtually eliminating diode conduction while preventing crossconduction
or shoot through. Figure 2 shows the switchnode voltage waveform for a synchronously rectified buck
converter during the synchronous rectification period. Illustrated are the relative effects of a fixed delay drive
scheme (constant, preset delays for the turnoff to turnon intervals), an adaptive delay drive scheme
(variable delays based on voltages sensed on the current switching cycle) and TI’s predictive delay drive
scheme. Since the diode voltage drop is greater than the conduction drop of the FET, the longer time spent
in diode conduction, the more power dissipated in the rectifier and the lower the efficiency. Also, not shown
in the figure, is the fact that the predictive delay circuit can actually prevent the body diode from becoming
forward biased at all, avoiding reverse recovery and its associated losses. This results in a significant power
savings when the main FET turns on.
The predictive gate drive architecture on the TPS40020/21 requires a minimum pulse width of greater than
150 ns for proper operation. At pulse widths below 150 ns, the lowside FET turnon could overlap the highside
FET turnoff leading to cross conduction in the power stage.
UDG01144
GND
Fixed Delay
Adaptive Delay
Predictive Delay
Channel Conduction
Body Diode Conduction
Figure 2. Switch Node Waveforms for Synchronous Buck Converter
相關(guān)PDF資料
PDF描述
TPS40020PWPRG4 0.01 A SWITCHING CONTROLLER, 1100 kHz SWITCHING FREQ-MAX, PDSO16
TPS40040DRBRG4 7.2 A SWITCHING CONTROLLER, 350 kHz SWITCHING FREQ-MAX, PDSO8
TPS40040DRBT 7.2 A SWITCHING CONTROLLER, 350 kHz SWITCHING FREQ-MAX, PDSO8
TPS40041DRBRG4 7.2 A SWITCHING CONTROLLER, 700 kHz SWITCHING FREQ-MAX, PDSO8
TPS40050QPWPRQ1 SWITCHING CONTROLLER, 1000 kHz SWITCHING FREQ-MAX, PDSO16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TPS40021PWPG4 功能描述:DC/DC 開(kāi)關(guān)控制器 Low Input Sync Buck Cntrlr source/sink RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
TPS40021PWPR 功能描述:DC/DC 開(kāi)關(guān)控制器 Low Input Sync Buck Cntrlr source/sink RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
TPS40021PWPRG4 功能描述:DC/DC 開(kāi)關(guān)控制器 Low Input Sync Buck Cntrlr source/sink RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開(kāi)關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK
TPS40022PWP 制造商:Texas Instruments 功能描述:
TPS40040 制造商:TI 制造商全稱:Texas Instruments 功能描述:LOW PIN COUNT, LOW VIN (2.5 V TO 5.5 V) SYNCHRONOUS BUCK DC-TO-DC CONTROLLER WITH ENABLE
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*