NCP1927
http://onsemi.com
11
Figure 3. Operation with Dual V
CC
Capacitors
I
CC
R
start
D1
D2
C1
C2
V
in
Aux Winding
V
CC
NCP1927
+
+
Figure 4. Startup Sequence of the NCP1927
Time
PDRV
FDRV
Time
V
CC(on)
V
CC(off)
V
CC(reset)
0 V
Time
I
CC5
I
CC3
+
ICC(FDRV)
I
CC1
+I
CC(FDRV)
+I
CC(PDRV)
V
CC
DRV
I
CC
PDRV
FDRV
FAULT MANAGEMENT
When the NCP1927 detects a nonlatching fault
(Shutdown Mode, TSD, and Flyback Overload), the drivers
are disabled, and V
CC
falls towards V
CC(off)
due to the IC
internal current consumption. Once V
CC
falls below
V
CC(off)
, the fault is reset and the IC internal current
consumption is reduced to the startup current, I
CC5
. V
CC
begins to rise as if power was initially applied and the device
resumes normal operation once V
CC
reaches V
CC(on)
. This
cycle between V
CC(on)
and V
CC(off)
is commonly referred to
as a V
CC
hiccup and is shown in Figure 5.
Figure 5. V
CC
During a V
CC
Hiccup
time
V
CC
time
DRV
VCC
ON
VCC
OFF
Device
Restarts
Fault
Occurs
Fault is Reset
time
ICC
ICC
4
ICC
5
ICC2
SHUTDOWN PIN
The Shutdown pin allows for external disabling of the
NCP1927. When V
Shutdown
is pulled above the shutdown
threshold, V
SHDN
(typically 1.0 V), both the flyback and
PFC drive outputs are immediately turned off, and a V
CC
hiccup occurs (see Figure 5). When V
CC
reaches V
CC(on)
,
the cycle repeats unless the NCP1927 is taken out of
shutdown. This is achieved when V
Shutdown
becomes less
than V
SHDN
. The NCP1927 leaves shutdown mode and will
start when V
CC
reaches V
CC(on)
according to the initial
poweron sequence. The V
CC
behavior during shutdown
mode is shown in Figure 6.
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
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
NCV8881PWR2G
IC REG TRPL BUCK/LINEAR 16SOIC
相关代理商/技术参数
NCP1937A1DR2G
制造商:ON Semiconductor 功能描述:COMBO PFC & QUAZI FLYBACK - Tape and Reel 制造商:ON Semiconductor 功能描述:REEL / COMBO PFC & QUAZI FLYBACK
NCP1937B1DR2G
制造商:ON Semiconductor 功能描述:COMBO PFC & QUAZI FLYBACK - Tape and Reel
NCP1937BADAPGEVB
制造商:ON Semiconductor 功能描述:ADPTR 90W PFC+QR<10MW - Bulk 制造商:ON Semiconductor 功能描述:BOARD EVAL FOR NCP1937 制造商:ON Semiconductor 功能描述:Power Management IC Development Tools 90 W Adapter PFC+QR 10 MW Eval Brd
NCP21WB333
制造商:MURATA 制造商全称:Murata Manufacturing Co., Ltd. 功能描述:for Surface Mounting Application
NCP21WB333J03RA
功能描述:热敏电阻 - NTC 33K OHM 5%
RoHS:否 制造商:EPCOS 电阻:10 kOhms 功率额定值:150 mW 容差:2 % 端接类型:Radial 系列:B57703M 工作温度范围:- 55 C to + 125 C
NCP21WB333K03RA
功能描述:热敏电阻 - NTC 33K OHM 10%
RoHS:否 制造商:EPCOS 电阻:10 kOhms 功率额定值:150 mW 容差:2 % 端接类型:Radial 系列:B57703M 工作温度范围:- 55 C to + 125 C
NCP21WB473
制造商:MURATA 制造商全称:Murata Manufacturing Co., Ltd. 功能描述:for Surface Mounting Application
NCP21WB473J03RA
功能描述:热敏电阻 - NTC 47K OHM 5%
RoHS:否 制造商:EPCOS 电阻:10 kOhms 功率额定值:150 mW 容差:2 % 端接类型:Radial 系列:B57703M 工作温度范围:- 55 C to + 125 C
