參數(shù)資料
型號: TC646VOA
廠商: Microchip Technology Inc.
英文描述: PWM Fan Speed Controller with Auto-Shutdown and FanSense⑩ Technology
中文描述: PWM風扇帶自動調速器關斷和FanSense⑩技術
文件頁數(shù): 14/28頁
文件大?。?/td> 473K
代理商: TC646VOA
TC646
DS21446C-page 14
2002 Microchip Technology Inc.
A base-current limiting resistor is required with bipolar
transistors. This is shown in Figure 5-6.
FIGURE 5-6:
R
BASE
.
Circuit For Determining
The correct value for this resistor can be determined as
follows:
V
OH
V
RSENSE
V
RBASE
I
BASE
= V
RSENSE
+ V
BE(SAT)
+ V
RBASE
= I
FAN
x R
SENSE
= R
BASE
x I
BASE
= I
FAN
/ h
FE
V
OH
is specified as 80% of V
DD
in Section 1.0,
“Electrical Characteristics”; V
BE(SAT)
is given in the
chosen transistor data sheet. It is now possible to solve
for R
BASE
.
EQUATION
Some applications benefit from the fan being powered
from a negative supply to keep motor noise out of the
positive supply rails. This can be accomplished as
shown in Figure 5-8. Zener diode D
1
offsets the -12V
power supply voltage, holding transistor Q
1
off when
V
OUT
is low. When V
OUT
is high, the voltage at the
anode of D
1
increases by V
OUT
, causing Q
1
to turn on.
Operation is otherwise the same as in the case of fan
operation from +12V.
FIGURE 5-7:
Output Drive Transistor Circuit Topologies.
Q
1
GND
V
DD
R
SENSE
R
BASE
V
OH
= 80% V
DD
+ V
RBASE
V
BE(SAT)
+
V
RSENSE
Fan
+
R
BASE
=
V
OH
- V
BE(SAT)
- V
RSENSE
I
BASE
Q
1
Q
1
Q
2
GND
V
DD
R
SENSE
R
BASE
V
OUT
V
OUT
Fan
a) Single Bipolar Transistor
Q
1
GND
V
DD
R
SENSE
V
OUT
c) N-Channel MOSFET
GND
V
DD
R
SENSE
R
BASE
Fan
b) Darlington Transistor Pair
Fan
相關PDF資料
PDF描述
TC647EOA PWM Fan Speed Controller with FanSense Technology
TC647VOA PWM Fan Speed Controller with FanSense Technology
TC647VPA PWM Fan Speed Controller with FanSense Technology
TC647VUA PWM Fan Speed Controller with FanSense Technology
TC647 PWM Fan Speed Controller with FanSense Technology
相關代理商/技術參數(shù)
參數(shù)描述
TC646VOA713 功能描述:馬達/運動/點火控制器和驅動器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 產(chǎn)品:Stepper Motor Controllers / Drivers 類型:2 Phase Stepper Motor Driver 工作電源電壓:8 V to 45 V 電源電流:0.5 mA 工作溫度:- 25 C to + 125 C 安裝風格:SMD/SMT 封裝 / 箱體:HTSSOP-28 封裝:Tube
TC646VPA 功能描述:馬達/運動/點火控制器和驅動器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 產(chǎn)品:Stepper Motor Controllers / Drivers 類型:2 Phase Stepper Motor Driver 工作電源電壓:8 V to 45 V 電源電流:0.5 mA 工作溫度:- 25 C to + 125 C 安裝風格:SMD/SMT 封裝 / 箱體:HTSSOP-28 封裝:Tube
TC646VUA 功能描述:馬達/運動/點火控制器和驅動器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 產(chǎn)品:Stepper Motor Controllers / Drivers 類型:2 Phase Stepper Motor Driver 工作電源電壓:8 V to 45 V 電源電流:0.5 mA 工作溫度:- 25 C to + 125 C 安裝風格:SMD/SMT 封裝 / 箱體:HTSSOP-28 封裝:Tube
TC646VUA713 功能描述:馬達/運動/點火控制器和驅動器 Shtdn & Fault Dtct RoHS:否 制造商:STMicroelectronics 產(chǎn)品:Stepper Motor Controllers / Drivers 類型:2 Phase Stepper Motor Driver 工作電源電壓:8 V to 45 V 電源電流:0.5 mA 工作溫度:- 25 C to + 125 C 安裝風格:SMD/SMT 封裝 / 箱體:HTSSOP-28 封裝:Tube
TC647 制造商:MICROCHIP 制造商全稱:Microchip Technology 功能描述:PWM Fan Speed Controller with FanSense Technology