- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄200634 > UPC29S78 Useage of Three-Terminal Regulators | User＇s Manual[05/2000] PDF資料下載
參數(shù)資料
| 型號(hào)： | UPC29S78 |
| 英文描述： | Useage of Three-Terminal Regulators | User＇s Manual[05/2000] |
| 中文描述： | 使用三端穩(wěn)壓器|用戶手冊[05/2000] |
| 文件頁數(shù)： | 34/35頁 |
| 文件大?。?/td> | 187K |
| 代理商： | UPC29S78 |
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頁當(dāng)前第34頁第35頁
User’s Manual G12702EJ8V0UM00
8
The operation of each block is explained in simple terms below.
<1> Reference voltage circuit
The reference voltage circuit, which determines the output voltage of the power supply IC, is an extremely
important part within the circuit. The method for configuring this circuit is as follows.
Band gap reference method: Use the forward characteristic between the base and emitter of the transistor.
The possibility of making the reference voltage 2 V or less is a feature of this method.
Figure 3-2 shows the principles of the band gap reference method. Figure 3-3 is a simple circuit diagram
of the band gap reference reference voltage used in the
PC7800A Series.
Figure 3-2. Band Gap Reference Circuit
Q3
R1
R3
VBE
VREF
VREF = VBE3
+
(
ln
)
R2
R3
R2
q
KT
R1
R2
Q1
Q2
I
GND
V
+
The reference voltage is as follows.
VREF = VBE3 + (IC2 + IB3)
R2
= VBE3 +
(
VBE) + IB3 R2
= VBE3 +
ln
................................................................................................................ (3 - 3)
The temperature coefficient is as follows.
=
+
ln
.............................................................................................................. (3 - 4)
By optimally choosing the ratio of
, a temperature compensated reference voltage is known to be
obtained.
.
R2
R3
R2
R1
R2
R3
R2
R3
KT
q
R2
R1
VREF
T
VBE3
T
K
q
R2
R3
R2
R1
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| UPC3025 | Useage of Three-Terminal Regulators | User＇s Manual[05/2000] |
| UPC1663B | Analog IC |
| UPC1663C | Analog IC |
| UPC1663P | Analog IC |
| UPC1664C | Analog IC |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| UPC29S78GR | 制造商:NEC 制造商全稱:NEC 功能描述:LOW DROPOUT VOLTAGE REGULATOR WITH ON/OFF FUNCTION |
| UPC29S78GR-E1-A | 制造商:Renesas Electronics Corporation 功能描述: |
| UPC29S78H | 制造商:NEC 制造商全稱:NEC 功能描述:LOW DROPOUT VOLTAGE REGULATOR WITH ON/OFF FUNCTION |
| UPC29S78TA | 制造商:NEC 制造商全稱:NEC 功能描述:LOW DROPOUT VOLTAGE REGULATOR WITH ON/OFF FUNCTION |
| UPC2A23P4 | 制造商: 功能描述: 制造商:undefined 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。