NCP1654
http://onsemi.com
20
Figure 45. BrownOut Protection
+
-
BO
4
R
boL
R
boU
C
BO
Vbo
V
in
+
V
ac
+
IN
V
boH
/ V
boL
V
boH
= 1.3 V, V
boL
= 0.7 V
After Device Operates
Before Device Operates
Hence a larger hysteresis of the brown out comparator is
needed, which is 0.7 V typical in this device. When V
bo
goes below than V
BOL
(0.7 V typical), the device turns off
the Drive output and keeps it off till V
bo
exceeds V
BOH
(1.3 V typical). When the device awakes after an offstate
(Undervoltage lockout or shutdown), the default threshold
is V
BOH
.
Overpower Limitation (OPL)
This is a second OCP with a threshold that is line
dependent. Sense current I
cs
represents the inductor current
I
L
and hence represents the input current approximately.
Input voltage signal V
bo
represents the rms input voltage.
The product (I
cs
?V
bo
) represents an approximated input
power (I
L
?V
ac
). It is illustrated in Figure 46.
Figure 46. OverPower Limitation
Current Mirror
>200 mVA?
OPL
+
RCS
ICS
CS
Vbo
4
3
R
SENSE
V
in
I
L
I
CS
+ I
L
R
SENSE
R
CS
When the product (I
cs
?V
bo
) is greater than a permissible
level 200 mVA, the device turns off the drive output so that
the input power is limited. The OPL is automatically
deactivated when the product (I
cs
?V
bo
) is lower than the
200 mVA level. This 200 mVA level corresponds to the
approximated input power (I
L
?V
ac
) to be smaller than the
particular expression in (Equation 23).
(eq. 23)
I
cs
V
bo
t 200 mVA
I
L
R
SENSE
R
CS
@
2 2
K
BO
p
@ V
ac
t 200 mVA
I
L
@ V
ac
t
R
CS
@ p
R
SENSE
@ K
BO
@ 50 2
mVA
Bias the Controller
It is recommended to add a typical 1 nF to 100 nF
decoupling capacitor next to the V
cc
pin for proper
operation. When the NCP1654 operates in follower boost
mode, the PFC output voltage is not always regulated at a
particular level under all application range of input voltage
and load power. It is not recommended to make a
lowvoltage bias supply voltage by adding an auxiliary
winding on the PFC boost inductor. Alternatively, it is
recommended to get the V
cc
biasing supply from the
2
nd
stage power conversion stage.
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
NCP1927DR2G
IC CTLR PFC/FLYBACK 16-SOIC
NCP380HMU21AATBG
IC CURRENT LIMIT SWITCH 6-UDFN
NCT1008DMT3R2G
TMP DIO MON/SMBUS 4CH 8WDFN
NCT210RQR2G
IC TEMP SENSOR LOC/REM 16QSOP
NCT214MT3R2G
IC TEMP SENSOR LOC/REM 10WDFN
NCT72CMNR2G
IC REMOTE THERMAL SENSOR 8-DFN
NCT7491RQR2G
IC REMOTE THERMAL MONITOR 24QSOP
NCT75MNR2G
IC SENSOR TEMP DGTL 8DFN
相关代理商/技术参数
NCP1654BD200R2G
功能描述:功率因数校正 IC NCP1654 - 200KHZ RoHS:否 制造商:Fairchild Semiconductor 开关频率:300 KHz 最大功率耗散: 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Reel
NCP1654BD65R2G
功能描述:功率因数校正 IC NCP1654-65K-B-SOIC RoHS:否 制造商:Fairchild Semiconductor 开关频率:300 KHz 最大功率耗散: 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Reel
NCP1654BP65G
功能描述:功率因数校正 IC NCP1654-65K-B-PDIP RoHS:否 制造商:Fairchild Semiconductor 开关频率:300 KHz 最大功率耗散: 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:SOIC-8 封装:Reel
NCP1654PFCGEVB
功能描述:电源管理IC开发工具 NCP1654 PWR FACT CONT EVB
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
NCP1729-SKT
制造商:P&S 功能描述:Sample Kit, including Two NCP1729SN35T1 and A Development Source CD-ROM 制造商:P&S 功能描述:Sample Kit,including Two NCP1729SN35T1 and A Development Source CD-ROM
NCP1729SN35T1
功能描述:电荷泵 Switched Cap Voltage RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 输出电压:- 1.5 V to - 5.5 V, 3 V to 11 V 输出电流:100 mA 电源电流:1 mA 最大工作温度:+ 70 C 封装 / 箱体:SOIC-8 Narrow 封装:Tube
NCP1729SN35T1G
功能描述:电荷泵 Switched Cap Voltage Inverter w/Shutdown RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 输出电压:- 1.5 V to - 5.5 V, 3 V to 11 V 输出电流:100 mA 电源电流:1 mA 最大工作温度:+ 70 C 封装 / 箱体:SOIC-8 Narrow 封装:Tube
NCP1729SN35T1G
制造商:ON Semiconductor 功能描述:Power Supply IC