參數(shù)資料
型號(hào)： L6566ATR
廠商： 意法半導(dǎo)體
元件分類： 基準(zhǔn)電壓源/電流源
英文描述： Multi-mode controller for SMPS with PFC front-end
中文描述： 多模式開(kāi)關(guān)電源控制器，PFC前端
文件頁(yè)數(shù)： 38/51頁(yè)
文件大小： 410K
代理商： L6566ATR
Application information
L6566A
38/51
5.12
Brownout protection
Brownout Protection is basically a not-latched device shutdown function activated when a
condition of mains undervoltage is detected. There are several reasons why it may be
desirable to shut down a converter during a brownout condition, which occurs when the
mains voltage falls below the minimum specification of normal operation.
Firstly, a brownout condition may cause overheating of the PFC front-end due to an excess
of RMS current. Secondly, brownout can also cause the PFC pre-regulator to work open
loop. This could be dangerous to the PFC itself and the downstream converter, should the
input voltage return abruptly to its rated value, given the slow response of PFC to transient
events. Finally, spurious restarts may occur during converter power down, hence causing
the output voltage not to decay to zero monotonically.
L6566A shutdown upon brownout is accomplished by means of an internal comparator, as
shown in the block diagram of
Figure 25
, which shows the basic circuit usage. The inverting
input of the comparator, available on the AC_OK pin (16), is supposed to sense a voltage
proportional to either the RMS or the peak mains voltage; the non-inverting input is
internally referenced to 0.485V with 35 mV hysteresis. If the voltage applied on the AC_OK
pin before the device starts operating does not exceed 0.485V or if it falls below 0.45 V while
the device is running, The AC_OK signal goes high, the pin Vcc_PFC is open and the
device shuts down, with the soft-start capacitor discharged and the gate-drive output low.
Additionally, in case the device has been latched off by some protection function (in which
case Vcc is oscillating between V
ccON
and V
ccON
- 0.5V) the AC_OK voltage falling below
0.45 V will clear the latch. This feature can be used to allow a quicker restart as the input
source is removed.
Figure 25. Brownout protection: internal block diagram and timing diagram
-
+
L6566A
AC_FAIL
AC_OK
Vcc
16
5
0.485V
0.45V
15 μA
R
H
R
L
Sensed
voltage
Vcc
(pin 5)
GD
(pin 4)
Vout
VAC_OK
(pin 16)
0.45V
I
HYS
15 μA
t
t
t
t
t
t
t
t
Vcc_PFC
(pin 6)
AC_FAIL
Sensed voltage
Vsen
ON
Vsen
OFF
0.485V
相關(guān)PDF資料
PDF描述
L6566B Multi-mode controller for SMPS
L6566BTR Multi-mode controller for SMPS
L6567 HIGH VOLTAGE DRIVER FOR CFL
L6567D HIGH VOLTAGE DRIVER FOR CFL
L6571B High Voltage Half Bridge Driver with Oscillator(帶晶振的高電壓半橋驅(qū)動(dòng)器)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
L6566B 功能描述:開(kāi)關(guān)變換器、穩(wěn)壓器與控制器 Multi Mode PWM Controller RoHS:否 制造商:Texas Instruments 輸出電壓:1.2 V to 10 V 輸出電流:300 mA 輸出功率: 輸入電壓:3 V to 17 V 開(kāi)關(guān)頻率:1 MHz 工作溫度范圍: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:WSON-8 封裝:Reel
L6566B_08 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:Multi-mode controller for SMPS
L6566BH 功能描述:電流型 PWM 控制器 Multimode Controller SMPS 800V <3mA 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
L6566BHTR 功能描述:電流型 PWM 控制器 MULTIMODE CONTROLLER SMPS 8V 3 mA 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
L6566BTR 功能描述:電流型 PWM 控制器 MultiMode Controller for SMPS 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)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)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

*
*
*