- 您現(xiàn)在的位置：買(mǎi)賣(mài)IC網(wǎng) > PDF目錄363215 > NCP1201P60G (ON SEMICONDUCTOR) PWM Current−Mode Controller for Universal Off−Line Supplies Featuring Low Standby Power with Fault Protection Modes PDF資料下載
參數(shù)資料
| 型號(hào)： | NCP1201P60G |
| 廠(chǎng)商： | ON SEMICONDUCTOR |
| 元件分類(lèi)： | 穩(wěn)壓器 |
| 英文描述： | PWM Current−Mode Controller for Universal Off−Line Supplies Featuring Low Standby Power with Fault Protection Modes |
| 中文描述： | SWITCHING CONTROLLER, 72 kHz SWITCHING FREQ-MAX, PDIP8 |
| 封裝： | HALOGEN FREE, BFR FREE AND ROHS COMPLIANT, PLASTIC, DIP-8 |
| 文件頁(yè)數(shù)： | 10/19頁(yè) |
| 文件大小： | 251K |
| 代理商： | NCP1201P60G |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)當(dāng)前第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)
NCP1201
http://onsemi.com
10
DETAILED OPERATING DESCRIPTION
Introduction
The NCP1201 implements a standard current mode
architecture where the switchoff time is dictated by the peak
current setpoint. This component represents the ideal
candidate where low partcount is the key criteria,
particularly in lowcost ACDC adapters, auxiliary supplies
etc. Due to its highperformance HighVoltage technology,
the NCP1201 incorporates all the necessary components
normally needed in UC384X based supplies: timing
components, feedback devices, lowpass filter and
selfsupply. This later point emphasizes the fact that
ON Semiconductor’s NCP1201 does NOT need an auxiliary
winding to operate: the device is self supplied from the
highvoltage rail and delivers a V
CC
to the IC. This system
is named the Dynamic SelfSupply (DSS).
Dynamic SelfSupply
The DSS principle is based on the charge/discharge of the
V
CC
bulk capacitor from a low level up to a higher level. We
can easily describe the current source operation following
simple logic equations:
POWERON: IF
V
CC
<
V
CCOFF
THEN
Current Source is ON, no output pulses
IF VCC decreasing >
V
CCON
THEN
Current Source is OFF, output is pulsing
IF VCC increasing <
V
CCOFF
THEN
Current Source is ON, output is pulsing
Typical values are:
V
CCOFF
= 12.5 V,
V
CCON
= 10.5 V
To better understand the operation principle, Figure 27
sketch offers the necessary explanation,
Figure 27. The Charge/Discharge Cycle Over a 10 F V
CC
Capacitor
10 mS
30 mS
50 mS
70 mS
90 mS
Current
Source
OFF
V
CC
Output Pulses
Vripple = 2 V
VCC
OFF
= 12.5 V
VCC
ON
= 10.5 V
ON
The DSS behavior actually depends on the internal IC
consumption and the MOSFET’s gate charge Qg. If we
select a MOSFET like the MTP2N60E, Qg max equals
22 nC. With a maximum switching frequency of 70 kHz for
the oscillator 60 kHz, the average power necessary to drive
the MOSFET (excluding the driver efficiency and
neglecting various voltage drops) is:
Pdriver
Fsw(max)
Qg
VCC
(eq. 1)
Where,
P
driver
= Average Power to drive the MOSFET
F
sw(max)
= Maximum switching frequency
Qg = MOSFET’s gate charge
V
CC
= VGS level applied to the gate of the MOSFET
To obtain an estimation of the driving current, simply
divide Pdriver by V
CC
,
Idriver
Fsw(max)
Qg
1.54 mA
(eq. 2)
The total standby power consumption at noload will
therefore heavily rely on the internal IC current
consumption plus the driving current (altered by the driver’s
efficiency). Suppose that the IC is supplied from a 350 VDC
line. The current flowing through pin 8 is a direct image of
the NCP1201 current consumption (neglecting the
switching losses of the HV current source). If I
CC2
equals
2.1 mA @ T
A
= 25
°
C, then the power dissipated (lost) by the
IC is simply: 350 V x 2.1 mA = 735 mW. For design and
reliability reasons, it would be interesting to reduce this
source of wasted power. In order to achieve that, different
methods can be used.
1. Use a MOSFET with lower gate charge Qg;
2. Connect pin through a diode (1N4007 typically) to
one of the mains input. The average value on pin 8
becomes:
VmainsPEAK
2
(eq. 3)
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| NCP1201P60 | PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Low Standby Power with Fault Protection Modes |
| NCP1201D100R2 | PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Low Standby Power with Fault Protection Modes |
| NCP1201D60R2 | PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Low Standby Power with Fault Protection Modes |
| NCP1201D60R2G | PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Low Standby Power with Fault Protection Modes |
| NCP1201P100 | PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Low Standby Power with Fault Protection Modes |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| NCP1203 | 制造商:ONSEMI 制造商全稱(chēng):ON Semiconductor 功能描述:PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Standby and Short Circuit |
| NCP1203/D | 制造商:未知廠(chǎng)家 制造商全稱(chēng):未知廠(chǎng)家 功能描述:PWM Current-Mode Controller for Universal Off-Line Supplies Featuring Standby and Short Circuit Protection |
| NCP1203_05 | 制造商:ONSEMI 制造商全稱(chēng):ON Semiconductor 功能描述:PWM Current−Mode Controller for Universal Off−Line Supplies Featuring Standby and Short Circuit Protection |
| NCP1203_10 | 制造商:ONSEMI 制造商全稱(chēng):ON Semiconductor 功能描述:PWM Current--Mode Controller for Universal Off--Line Supplies Featuring Standby and Short Circuit Protection |
| NCP1203D100R2 | 功能描述:電流型 PWM 控制器 100KHz Current Mode RoHS:否 制造商:Texas Instruments 開(kāi)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 |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。