參數(shù)資料
型號(hào)： ML4425
廠商： Fairchild Semiconductor Corporation
英文描述： Sensorless BLDC Motor Controller
中文描述： 傳感器無(wú)刷直流電機(jī)控制器
文件頁(yè)數(shù)： 9/16頁(yè)
文件大?。?/td> 167K
代理商： ML4425
PRODUCT SPECIFICATION
ML4425
REV. 1.0.2 7/2/01
9
The maximum frequency on the VCO pin is found by:
The voltage at the VCO/TACH pin is equal to the rotor
speed. The voltage at SPEED FB is controlled by the back
EMF sampler.
Back EMF Sampler
The input to the voltage controlled oscillator is the back
EMF sampler. The back EMF sense pins FB A, FB B, and
FB C inputs to the back EMF sampler require a signal from
the motor phase leads that is below the V
DD
of the ML4425.
The phase sense input impedance is 8k
. This requires a
series resistor RES1 from the motor phase lead as shown in
Figure 6 based on the following equation:
The back EMF sampler takes the motor phase voltages
divided down to signals that are less than V
DD
(12V nomi-
nal) and calculates the neutral point of the motor by the fol-
lowing equation:
This allows the ML4425 to compare the back EMF signal to
the motor’s neutral point without the need for bringing out an
extra wire on a WYE wound motor. For DELTA wound
motors there is no physical neutral to bring out, so this refer-
ence point must be calculated in any case.
Figure 5. External VCO Component Connections
The back EMF sampler measures the motor phase that is not
driven (i.e. if LA and HB are on, then phase A is driven low,
phase B is driven high, and phase C is sampled). The sam-
pled phase provides a back EMF signal that is compared
against the neutral of the motor. The sampler is controlled by
the commutation state machine. The sampled back EMF is
compared to the neutral through an error amplifier. The out-
put of the error amplifier outputs a charging or discharging
current to SPEED FB, which provides the control voltage to
the VCO.
f
MAX
0.05
N
×
RPM
MAX
×
=
(3)
RES1
670
V
V
MOTOR
10V
–
(
)
×
=
(4)
Neutral
------------+
+
=
(5)
CVCO
CVCO
4.3V
0V
5V
2.3V
RVCO
SPEED
FB
CVCO
RVCO
VOLTAGE
CONTROLLED
OSCILLATOR
VCO/TACH
VCO/TACH
RESET
(FROM CAT)
FROM
BACK EMF
SAMPLER
& RAMP
GENERATOR
Figure 6. Back EMF Sampler Detailed Block Diagram
NEUTRAL
SIMULATOR
Φ
A +
Φ
B +
Φ
C
6
MULTIPLEXER
COMMUTATION
STATE MACHINE
gm =
1
8k
4k
4k
4k
4k
4k
4k
+
–
SIGN
CHANGER
TO
SPEED FB
FB A
RES1
RES2
RES3
FB B
FB C
F/R
MOTOR
Φ
C
F/R
MOTOR
Φ
B
MOTOR
Φ
A
相關(guān)PDF資料
PDF描述
ML4425CP Sensorless BLDC Motor Controller
ML4425CS Sensorless BLDC Motor Controller
ML4425IP Sensorless BLDC Motor Controller
ML4425IS Sensorless BLDC Motor Controller
ML4426 Bi-directional Sensorless BLDC Motor Controller(雙向無(wú)傳感無(wú)刷直流電機(jī)控制器)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ML4425CH 制造商:MICRO-LINEAR 制造商全稱:MICRO-LINEAR 功能描述:Sensorless BLDC Motor Controller
ML4425CP 功能描述:開(kāi)關(guān)變換器、穩(wěn)壓器與控制器 BLDC Motor Control Sensorless 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(kāi)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
ML4425CS 功能描述:開(kāi)關(guān)變換器、穩(wěn)壓器與控制器 BLDC Motor Control Sensorless 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(kāi)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
ML4425CSX 功能描述:開(kāi)關(guān)變換器、穩(wěn)壓器與控制器 BLDC Motor Control Sensorless 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(kāi)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
ML4425IH 制造商:MICRO-LINEAR 制造商全稱:MICRO-LINEAR 功能描述:Sensorless BLDC Motor Controller
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*