參數(shù)資料
型號(hào)： FAN9612MX
廠商： Fairchild Semiconductor
文件頁(yè)數(shù)： 8/36頁(yè)
文件大小： 1561K
描述： IC CTLR PFC DUAL BCM 16SOICN
標(biāo)準(zhǔn)包裝： 1
模式： 臨界傳導(dǎo)（BCM）
頻率 - 開(kāi)關(guān)： 16.5kHz ~ 525kHz
電流 - 啟動(dòng)： 80µA
電源電壓： 9 V ~ 18 V
工作溫度： -40°C ~ 125°C
安裝類(lèi)型： 表面貼裝
封裝/外殼： 16-SOIC（0.154"，3.90mm 寬）
供應(yīng)商設(shè)備封裝： 16-SOIC N
包裝： 標(biāo)準(zhǔn)包裝
其它名稱(chēng)： FAN9612MXFSDKR
 
?2008 Fairchild Semiconductor Corporation
 
www.fairchildsemi.com
FAN9612 " Rev. 1.1.7
8
Theory of Operation
1.   Boundary Conduction Mode
The boost converter is the most popular topology for
power factor correction in AC-to-DC power supplies.
This popularity can be attributed to the continuous input
current waveform provided by the boost inductor and to
the fact that the boost converters input voltage range
includes 0 V. These fundamental properties make close
to unity power factor easier to achieve.
L
 
Figure 6.   Basic PFC Boost Converter
The   boost   converter   can   operate   in   continuous
conduction mode (CCM) or in boundary conduction
mode (BCM). These two descriptive names refer to the
current flowing in the energy storage inductor of the
boost power stage.
 
Figure 7.   CCM vs. BCM Control
As the names indicate, the current in Continuous
Conduction Mode (CCM) is continuous in the inductor;
while in Boundary Conduction Mode (BCM), the new
switching period is initiated when the inductor current
returns to zero.
There are many fundamental differences in CCM and
BCM operations and the respective designs of the boost
converter.
The FAN9612 utilizes the boundary conduction mode
control algorithm. The fundamental concept of this
operating mode is that the inductor current starts from
zero in each switching period, as shown in the lower
waveform in Figure 7. When the power transistor of the
boost converter is turned on for a fixed amount of time,
the peak inductor current is proportional to the input
voltage. Since the current waveform is triangular, the
average   value   in   each   switching   period   is   also
proportional to the input voltage. In the case of a
sinusoidal input voltage waveform, the input current of
the converter follows the input voltage waveform with
very high accuracy and draws a sinusoidal input current
from   the   source.   This   behavior   makes   the   boost
converter in BCM operation an ideal candidate for
power factor correction.
This mode of control of the boost converter results in a
variable switching frequency. The frequency depends
primarily    on    the    selected    output    voltage,    the
instantaneous value of the input voltage, the boost
inductor value, and the output power delivered to the
load. The operating frequency changes as the input
voltage follows the sinusoidal input voltage waveform.
The lowest frequency operation corresponds to the peak
of the sine waveform at the input of the boost converter.
Even larger frequency variation can be observed as the
output power of the converter changes, with maximum
output   power   resulting   in   the   lowest   operating
frequency. Theoretically, under zero-load condition, the
operating   frequency   of   the   boost   converter   would
approach infinity. In practice, there are natural limits to
the highest switching frequency. One such limiting factor
is the resonance between the boost inductor and the
parasitic capacitances of the MOSFET, the diode, and
the winding of the choke, in every switching cycle.
Another important characteristic of the BCM boost
converter is the high ripple current of the boost inductor,
which goes from zero to a controlled peak value in every
switching   period.   Accordingly,   the   power   switch   is
stressed with high peak current. In addition, the high
ripple current must be filtered by an EMI filter to meet
high-frequency     noise     regulations     enforced     for
equipment connecting to the mains. The effects usually
limit the practical output power level of the converter.
 
相關(guān)PDF資料
PDF描述
FL6961MY IC CTLR PFC SGL FLYBACK 8-SOIC
IR1150ISTRPBF IC PFC CONTROLLER CCM 8-SOIC
IR1152STRPBF IC PFC ONE CYCLE CONTROL 8SOIC
IR1153STRPBF IC PFC ONE CYCLE CONTROL 8SOIC
IR1155STRPBF IC PFC ONE CYCLE CONTROL 8SOIC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
FAN9612Y FAN9613Y WAF 制造商:Fairchild Semiconductor Corporation 功能描述:
FAN9613_YAC3026B WAF 制造商:Fairchild Semiconductor Corporation 功能描述:
FAN9621 制造商:FAIRCHILD 制造商全稱(chēng):Fairchild Semiconductor 功能描述:Interleaved Dual BCM PFC Controller
FAN-AC3 制造商:Cosel Usa Inc 功能描述:Optional Accessories, OP Series
FAN-AC3-F 制造商:Cosel Usa Inc 功能描述:Optional Accessories, OP Series
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

*
*
*