參數(shù)資料
型號(hào)： NCP1239
廠商： ON SEMICONDUCTOR
英文描述： Low−Standby High Performance PWM Controller
文件頁(yè)數(shù)： 21/38頁(yè)
文件大?。?/td> 1145K
代理商： NCP1239
NCP1239
http://onsemi.com
21
The PFC controller connection is really straightforward as
testified by Figure 39: simply connect to Pin 1, the base of
a pnp transistor that connects the PFC’s V
CC
to the NCP1239
one (perhaps add a small decoupling capacitor like a 0.1 F
on the PFC) and this is all! The PFC startup network goes
away as it is fully supplied by the PWM auxiliary winding
and even high quiescent current devices do not hamper the
standby power since they are completely disconnected in
standby.
Figure 39.
The NCP1239 turns off the pnp Q1 during the standby so that the PFC controller is no longer supplied in this mode.
1
16
2
3
4
15
14
13
NCP1239
5
12
6
7
8
11
10
9
1
8
2
3
4
7
6
5
PFC Controller
PFC_V
CC
V
CC
+
+
PFC stage
Q1
Rectified
AC line
ShortCircuit or Overload Condition
The NCP1239 differs from other controllers in the sense
that a fault condition is detected independently of the
auxiliary voltage level. In auxiliary supplybased power
supplies, it is necessary that the (isolated) secondary output
conditions properly reflects on the (nonisolated) auxiliary
winding in order to instruct the controller on what is
happening on the other side of the transformer. For the
following reasons, it sometimes becomes extremely
difficult to build an efficient shortcircuit protection
circuitry and even more difficult to implement over power
detection (e.g. the output load is 25% above the nominal
value but Vout is still present).
The primary leakage inductance is high:
this is probably
the main reason why building efficient shortcircuit
detection is difficult. When the power switch opens, the
leakage inductance superimposes a large overvoltage spike
on the drain voltage. This spike is seen on the secondary side
but also on the auxiliary winding. Unfortunately, since the
V
CC
capacitor and the auxiliary diode form a peak rectifier,
the auxiliary V
CC
often depends on this peak value rather
than the true plateau which corresponds to the output level.
相關(guān)PDF資料
PDF描述
NCP1239FDR2 Low−Standby High Performance PWM Controller
NCP1239FDR2G Low−Standby High Performance PWM Controller
NCP1239VDR2 Low−Standby High Performance PWM Controller
NCP1239VDR2G Low−Standby High Performance PWM Controller
NCP1271 Soft−Skip Mode Standby PWM Controller with Adjustable Skip Level and External Latch
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
NCP1239D 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Low-Standby High Performance PWM Controller
NCP1239F 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:AC-DC Offline Switching Controllers/Regulators
NCP1239FDR2 功能描述:電流型 PWM 控制器 Low Standby Power RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時(shí)間: 下降時(shí)間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14
NCP1239FDR2G 功能描述:電流型 PWM 控制器 Low Standby Power High Performance PWM RoHS:否 制造商:Texas Instruments 開關(guān)頻率:27 KHz 上升時(shí)間: 下降時(shí)間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14
NCP1239V 制造商:ONSEMI 制造商全稱:ON Semiconductor 功能描述:AC-DC Offline Switching Controllers/Regulators
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

*
*
*