參數(shù)資料
型號(hào): NCP1200P40
廠商: ON SEMICONDUCTOR
元件分類: 穩(wěn)壓器
英文描述: PWM Current-Mode Controller for Low-Power Universal Off-Line Supplies
中文描述: 0.25 A SWITCHING CONTROLLER, 48 kHz SWITCHING FREQ-MAX, PDIP8
封裝: PLASTIC, DIP-8
文件頁數(shù): 11/16頁
文件大?。?/td> 151K
代理商: NCP1200P40
NCP1200
http://onsemi.com
11
Figure 21. A negative spike takes place on the Bulk capacitor at the switchoff sequence
Simple and inexpensive cures exist to prevent from
internal parasitic SCR activation. One of them consists in
inserting a resistor in series with the highvoltage pin to
keep the negative current to the lowest when the bulk
becomes negative (Figure 22). Please note that the negative
spike is clamped to –2 x Vf due to the diode bridge. Please
refer to AND8069/D for power dissipation calculations.
Another option (Figure 23) consists in wiring a diode from
V
CC
to the bulk capacitor to force V
CC
to reach UVLOlow
sooner and thus stops the switching activity before the bulk
capacitor gets deeply discharged. For security reasons, two
diodes can be connected in series.
Figure 22. A simple resistor in series avoids any
latchup in the controller
CV
CC
D3
1N4007
8
7
6
5
1
2
3
4
+
Cbulk
+
1
3
CV
CC
Rbulk
> 4.7 k
8
7
6
5
1
2
3
4
+
Cbulk
+
1
2
3
Figure 23. or a diode forces V
CC
to reach
UVLOlow sooner
A Typical Application
Figure 24 depicts a lowcost 3.5 W ACDC 6.5 V wall
adapter. This is a typical application where the wallpack
must deliver a raw DC level to a given internally regulated
apparatus: toys, calculators, CD players etc. Due to the
inherent shortcircuit protection of the NCP1200, you only
need a bunch of components around the IC, keeping the final
cost at an extremely low level. The transformer is available
from different suppliers as detailed on the following page.
相關(guān)PDF資料
PDF描述
NCP1200P40G PWM Current-Mode Controller for Low-Power Universal Off-Line Supplies
NCP1200P60 PWM Current-Mode Controller for Low-Power Universal Off-Line Supplies
NCP1200P60G PWM Current-Mode Controller for Low-Power Universal Off-Line Supplies
NCP1200P100 PWM Current-Mode Controller for Low-Power Universal Off-Line Supplies
NCP1200P100G PWM Current-Mode Controller for Low-Power Universal Off-Line Supplies
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
NCP1200P40G 功能描述:電流型 PWM 控制器 40KHz Current Mode SMPS 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
NCP1200P40G 制造商:ON Semiconductor 功能描述:Pulse Width Modulation (PWM) Controller
NCP1200P60 功能描述:電流型 PWM 控制器 60KHz Current Mode 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
NCP1200P60G 功能描述:電流型 PWM 控制器 60KHz Current Mode SMPS 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
NCP1200P60G 制造商:ON Semiconductor 功能描述:Pulse Width Modulation (PWM) Controller