- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄30770 > LTC3766IGN#PBF (LINEAR TECHNOLOGY CORP) SWITCHING CONTROLLER, 316 kHz SWITCHING FREQ-MAX, PDSO28 PDF資料下載
參數(shù)資料
| 型號： | LTC3766IGN#PBF |
| 廠商： | LINEAR TECHNOLOGY CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING CONTROLLER, 316 kHz SWITCHING FREQ-MAX, PDSO28 |
| 封裝： | 0.150 INCH, LEAD FREE, PLASTIC, SSOP-28 |
| 文件頁數(shù)： | 19/60頁 |
| 文件大小： | 607K |
| 代理商： | LTC3766IGN#PBF |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁當前第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁
LTC3766
26
3766f
APPLICATIONS INFORMATION
completely recovered by the active clamp capacitor. For
most applications, these assumptions are valid and the
above equation is a good approximation.
The active clamp P-channel MOSFET has the same BVDSS
requirement as that of the N-channel MOSFET. Since the
P-channel MOSFET only handles the magnetizing current,
it is normally much smaller (typically a SOT package).
To accommodate abnormal transients, use a P-channel
MOSFET that has a pulsed drain current rating of 2A or
higher. Also, note that when the N-channel MOSFET turns
off, the leakage inductance will momentarily force the re-
flected load current into the body diode of the P-channel
MOSFET. Consequently, the body diode should be rated
to handle a pulsed forward current of:
ID(MAX) =
NS
NP
IMAX
In some cases, it may be more practical to add a separate
diode in parallel with the body diode of the P-channel
MOSFET.
The primary-side P-channel MOSFET may be driven by a
simple level-shift circuit that shifts down the drive voltage
on the LTC3765 AG pin. Alternatively, the level-shift circuit
can be omitted if the source of the P-channel MOSFET
is returned to the VCC pin of the LTC3765. Refer to the
LTC3765 data sheet for details.
In nonisolated applications where the LTC3766 is used
standalone, it is necessary to use a resonant reset tech-
nique instead of the active clamp reset. As a result, there
are special considerations in selecting the primary-side
MOSFET. See the Nonisolated Applications section for
additional information.
Secondary-Side Power MOSFET Selection
On the secondary side, the peak-to-peak drive level for the
N-channel MOSFETs is determined by the VCC pin on the
LTC3766. Assuming that one or both of the linear regula-
tors in the LTC3766 are used, the VCC regulation voltage
can be set to either 7V or 8.5V as needed for driving the
gates of the MOSFETs.
The first step in selecting the secondary-side MOSFETs is
todeterminetheneededbreakdownvoltage.Themaximum
voltageseenbythesynchronousMOSFETisapproximately:
VDS(SG) =1.2
NS
NP
VIN(MAX)
where the factor of 1.2 has been added to allow for ringing
andovershoot.Thisassumesthatasnubberhasbeenused
on the secondary side of the main transformer (see the RC
Snubbers section). If no snubber is used, the ringing and
peak overshoot will be considerably higher. The maximum
voltage seen by the forward MOSFET is approximately:
VDS(FG) =
1.2 VOUT
1–
VOUT
VIN(MIN)
NP
NS
where the factor of 1.2 has again been added to allow for
ringing and overshoot.
Having determined the BVDSS requirement for the forward
and synchronous MOSFETs, the next step is to choose the
on-resistance. Since both secondary-side MOSFETs are
zero-voltage switched, choose MOSFETs that have a low
RDS(ON) and have been optimized for use as synchronous
rectifiers, including a body diode with a fast reverse re-
covery if possible. In most applications, the nominal input
voltage will correspond to approximately 50% duty cycle,
sotheforwardandsynchronousMOSFETswillbeselected
to have the same RDS(ON). The power loss associated with
the forward MOSFET can be approximated by:
PFG =
NP
NS
VOUT IMAX
( )2
VIN
1
+ δ
( )RDS(ON)
+QGTOTVBIASfSW
where
δisthetemperaturedependenceoftheon-resistance
and VBIAS is the input to the LTC3766 linear regulator (if
used). The value for QGTOT can be taken from the VGS
versus QG curve given in the MOSFET data sheet. QGTOT
is the value of QG when VGS = VCC, where VCC is the
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC3766HGN#TRPBF | SWITCHING CONTROLLER, 316 kHz SWITCHING FREQ-MAX, PDSO28 |
| LTC3766HUFD#TRPBF | SWITCHING CONTROLLER, 316 kHz SWITCHING FREQ-MAX, PQCC28 |
| LTC3766IUFD#TRPBF | SWITCHING CONTROLLER, 316 kHz SWITCHING FREQ-MAX, PQCC28 |
| LTC3766MPUFD#TRPBF | SWITCHING CONTROLLER, 316 kHz SWITCHING FREQ-MAX, PQCC28 |
| LTC3766IGN#TRPBF | SWITCHING CONTROLLER, 316 kHz SWITCHING FREQ-MAX, PDSO28 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC3766IUFD#PBF | 功能描述:IC CONTROLLER SYNCH 28QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 電源控制器，監(jiān)視器 系列:Direct Flux Limit™, PolyPhase® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 應(yīng)用:多相控制器 輸入電壓:- 電源電壓:9 V ~ 14 V 電流 - 電源:- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP（5x5） 包裝:帶卷 (TR) |
| LTC3766IUFD#TRPBF | 功能描述:IC CONTROLLER SYNCH 28QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 電源控制器，監(jiān)視器 系列:Direct Flux Limit™, PolyPhase® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 應(yīng)用:多相控制器 輸入電壓:- 電源電壓:9 V ~ 14 V 電流 - 電源:- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP（5x5） 包裝:帶卷 (TR) |
| LTC3766MPGN#PBF | 功能描述:IC CONTROLLER SYNCH 28SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 電源控制器，監(jiān)視器 系列:Direct Flux Limit™, PolyPhase® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 應(yīng)用:多相控制器 輸入電壓:- 電源電壓:9 V ~ 14 V 電流 - 電源:- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP（5x5） 包裝:帶卷 (TR) |
| LTC3766MPGN#TRPBF | 功能描述:IC CONTROLLER SYNCH 28SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 電源控制器，監(jiān)視器 系列:Direct Flux Limit™, PolyPhase® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 應(yīng)用:多相控制器 輸入電壓:- 電源電壓:9 V ~ 14 V 電流 - 電源:- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP（5x5） 包裝:帶卷 (TR) |
| LTC3766MPUFD#PBF | 功能描述:IC CONTROLLER SYNCH 28QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 電源控制器，監(jiān)視器 系列:Direct Flux Limit™, PolyPhase® 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 應(yīng)用:多相控制器 輸入電壓:- 電源電壓:9 V ~ 14 V 電流 - 電源:- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:40-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:40-TQFN-EP（5x5） 包裝:帶卷 (TR) |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。