- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄372078 > S-8521B25MC-ATK-T2 Analog IC PDF資料下載
參數(shù)資料
| 型號： | S-8521B25MC-ATK-T2 |
| 英文描述： | Analog IC |
| 中文描述： | 模擬IC |
| 文件頁數(shù)： | 13/37頁 |
| 文件大?。?/td> | 599K |
| 代理商： | S-8521B25MC-ATK-T2 |
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頁當(dāng)前第13頁第14頁第15頁第16頁第17頁第18頁第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
PWM Control & PWM/PFM Control Step-Down Switching Regulator-Controllers
Rev.7.2
S-8520/8521 Series
Seiko Instruments Inc.
13
For reference purpose, some efficiency data has been included in this document. For applications with
an input voltage range of 10 V or less, data was obtained by using TM6201 of Toyoda Automatic Loom
Works, Ltd. IRF7606, a standard of International Rectifier, was used for applications with an input
voltage range over 10 V. Refer to "Reference Data."
5.2 Bipolar PNP type
Figure 7 shows a sample circuit diagram using Toshiba 2SA1213-Y for the bipolar transistor (PNP).
The driving capacity for increasing the output current by means of a bipolar transistor is determined by
the h
FE
-value and the Rb-value of that bipolar transistor.
VIN
EXT
2SA1213-Y
VIN
Rb
Cb
Figure 7
The Rb-value is given by the following equation:
Ib
|IEXTL|
0.4
VIN-0.7
Rb=
Find the necessary base current Ib using the h
FE
- value of bipolar transistor by the equation, Ib =
Ipk/hFE, and select a smaller Rb-value.
A small Rb-value will certainly contribute to increasing the output current, but it will also adversely
affect the efficiency. Moreover, in practice, a current may flow as the pulses or a voltage drop may take
place due to the wiring resistance or some other reason. Determine an optimum value through
experimentation.
In addition, if speed-up capacitor Cb is inserted in parallel with resistance Rb, as shown in Figure 7, the
switching loss will be reduced, leading to a higher efficiency.
Select a Cb-value by using the following equation as a guide:
2
π
xRb x f
OSC
x 0.7
1
Cb
≤
However, the practically-reasonable Cb value differs depending upon the characteristics of the bipolar
transistor. Optimize the Cb value based on the experiment result.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| S-8521B30MC-ATP-T2 | Analog IC |
| S-8521B33MC-ATS-T2 | Analog IC |
| S-8521B50MC-AUJ-T2 | Analog IC |
| S-8521C25MC-BTK-T2 | Analog IC |
| S-8521C30MC-BTP-T2 | Analog IC |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| S-8521B25MC-ATKT2G | 功能描述:DC/DC 開關(guān)控制器 2.5V Step-Dn PWM/PFM 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 |
| S-8521B26MC-ATLT2G | 功能描述:DC/DC 開關(guān)控制器 Step Down SWR PWM/ PFM 180kHz 60uA Iq 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 |
| S-8521B27MC-ATM-T2 | 功能描述:DC/DC 開關(guān)控制器 2.7V Step-Dn PWM/PFM 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 |
| S-8521B27MC-ATMT2G | 功能描述:DC/DC 開關(guān)控制器 2.7V Step-Dn PWM/PFM 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 |
| S-8521B28MC-ATN-T2 | 功能描述:DC/DC 開關(guān)控制器 2.8V Step-Dn PWM/PFM 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)。