- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄365555 > Si786DSG (Vishay Intertechnology,Inc.) Dual-Output Power-Supply Controller PDF資料下載
參數(shù)資料
| 型號： | Si786DSG |
| 廠商： | Vishay Intertechnology,Inc. |
| 英文描述： | Dual-Output Power-Supply Controller |
| 中文描述： | 雙輸出電源控制器 |
| 文件頁數(shù)： | 8/14頁 |
| 文件大小： | 130K |
| 代理商： | SI786DSG |
Si786
Vishay Siliconix
www.vishay.com
8
Document Number: 70189
S-40807—Rev. J, 26-Apr-04
ORDERING INFORMATION
Lead (Pb)-Free
Part Number
Part Number
Temp Range
V
OUT
Si786CG
Si786CG-T1
Si786CRG
Si786CRG-T1
Si786CSG
Si786CSG-T1
Si786LG
Si786LG-T1
Si786LRG
Si786LRG-T1
Si786LSG
Si786LSG-T1
Si786DG
Si786DG-T1
Si786DRG
Si786DRG-T1
Si786DSG
Si786DSG-T1
3 3 V
3.3 V
Si786CG-T1—E3
C-Grade
0 to 70 C
3 45 V
3.45 V
Si786CRG-T1—E3
3 6 V
3.6 V
Si786CSG-T1—E3
3 3 V
3.3 V
Si786LG-T1—E3
L-Grade
10 to 90 C
3 45 V
3.45 V
Si786LRG-T1—E3
3 6 V
3.6 V
Si786LSG-T1—E3
3 3 V
3.3 V
Si786DG-T1—E3
D-Grade
40 to 85 C
3 45 V
3.45 V
Si786DRG-T1—E3
3 6 V
3.6 V
Si786DSG-T1—E3
Demo Board
Temp Range
Board Type
Si786DB
0 to 70 C
Surface Mount
DESCRIPTION OF OPERATION
The Si786 is a dual step-down converter, which takes a 5.5-V
to 30-V input and supplies power via two PWM controllers (see
Figure 1). These 5-V and 3.3-V supplies run on an optional
300-kHz or 200-kHz internal oscillator, or an external sync
signal. Amount of output current is limited by external
components, but can deliver greater than 6 A on either supply.
As well as these two main Buck controllers, additional loads
can be driven from two micropower linear regulators, one 5 V
(V
L
) and the other 3.3 V (REF)—see Figure 2. These supplies
are each rated to deliver 5 mA. If the linear regulator circuits fall
out of regulation, both Buck controllers are shut down.
Two voltage comparators with adjustable output voltages are
included in the Si786. They can be used for gate drive in load
switching applications, where n-channel MOSFETs are used.
Logic level voltages can be generated as well, for instance to
serve as P interfacing (e.g. a Power-good signal).
3.3-V Switching Supply
The 3.3-V supply is regulated by a current-mode PWM
controller in conjunction with several externals: two n-channel
MOSFETs, a rectifier, an inductor and output capacitors (see
Figure 1). The gate drive supplied by DH
3
needs to be greater
than V
L
, so it is provided by the bootstrap circuit consisting of
a 100-nF capacitor and diode connected to BST
3
.
A low-side switching MOSFET connected to DL
3
increases
efficiency by reducing the voltage across the rectifier diode. A
low value sense resistor in series with the inductor sets the
maximum current limit, to disallow current overloads at
power-on or in short-circuit situations.
The soft-start feature on the Si786 is capacitor programmable;
pin SS
3
functions as a constant current source to the external
capacitor connected to GND. Excess currents at power-on are
avoided, and power-supplies can be sequenced with different
turn-on delay times by selecting the correct capacitor value.
5-V Switching Supply
The 5-V supply is regulated by a current-mode PWM controller
which is nearly the same as the 3.3-V output. The dropout
voltage across the 5-V supply, as shown in the schematic in
Figure 1, is 400 mV (typ) at 2 A. If the voltage at V+ falls, nearing
5 V, the 5-V supply will lower as well, until the V
L
linear regulator
output falls below the 4-V undervoltage lockout threshold.
Below this threshold, the 5-V controller is shut off.
The frequency of both PWM controllers is set at 300 kHz when
the SYNC pin is tied to REF. Connecting SYNC to either GND
or V
L
sets the frequency at 200 kHz.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| Si786DSG-T1 | Dual-Output Power-Supply Controller |
| Si786LG | Dual-Output Power-Supply Controller |
| Si786LG-T1 | Dual-Output Power-Supply Controller |
| Si786LRG | Dual-Output Power-Supply Controller |
| Si786LRG-T1 | Dual-Output Power-Supply Controller |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| SI786DSG-E3 | 功能描述:開關(guān)變換器、穩(wěn)壓器與控制器 Dual 3.6V Step-Down 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 |
| SI786DSG-T1 | 功能描述:開關(guān)變換器、穩(wěn)壓器與控制器 Dual 3.6V Step-Down 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 |
| SI786DSG-T1-E3 | 功能描述:開關(guān)變換器、穩(wěn)壓器與控制器 Dual 3.6V Step-Down 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 |
| SI786LG | 功能描述:DC/DC 開關(guān)控制器 3.3V Power Sup Cont RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK |
| SI786LG-E3 | 功能描述:DC/DC 開關(guān)控制器 3.3V Power Sup Cont RoHS:否 制造商:Texas Instruments 輸入電壓:6 V to 100 V 開關(guān)頻率: 輸出電壓:1.215 V to 80 V 輸出電流:3.5 A 輸出端數(shù)量:1 最大工作溫度:+ 125 C 安裝風(fēng)格: 封裝 / 箱體:CPAK |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。