參數(shù)資料
型號: FAN8621B
廠商: FAIRCHILD SEMICONDUCTOR CORP
元件分類: 運動控制電子
英文描述: 12V Spindle Motor and Voice Coil Motor Driver IC(12V電源的主軸電機和語音線圈電機驅動器)
中文描述: VOICE COIL MOTOR CONTROLLER, PQFP52
封裝: 14 X 14 MM, HEAT SINK, QFP-48
文件頁數(shù): 13/22頁
文件大?。?/td> 427K
代理商: FAN8621B
FAN8621B; PRELIMINARY
13
The spindle motor speed is controlled by SPLL which consists of Synchronous F/I converter , loop filter , and inner current
control loop. F/I converter compares RPM reference time with 12 FG time one rotation of spindle for 8 pole motor. The time
difference is converted into charge/discharge current source, and fed to loop filter consisting of external RC network. Loop fil-
ter acts ad speed controller and it’s output becomes spindle output current set point. If spindle motor speed is greater than tar-
get speed, switch s2 is turned on, thus decreasing output voltage of loop filter. Current limiting during start-up is achieved by
sensing the voltage across the sense resistor connected PCS (pin 33). This limit the loop filer output. The output of loof filter is
compared with internal 2.5V reference. If the difference is over 0.75V, the output is limited and scaled down. When the output
of loof filter is 1.75V(2.5V-0.75V), the output of limitter is 0. The maximum output of limitter is 0.4V when the output of loof
filter is over 3.25V. So spindle output current is linearly controlled by level shifted current set point driving high side vertical
PNP TR of spindle output driver. Overall concept of SPM speed control is shown Figure3.
Figure 3. Speed Control of SPM
Indirect Rotor Position Sensing and Commutation
The back-EMF comparator detects the instant at which the back-EMF in the unexcited phase cross as zero. The commutation
timing and sequencing for driver outputs is determined by internal commutation logic based on back-EMF ZCP (zero crossing
point). Commutation is initiated in advance of ZCP, 30
°
(electrical) for hard commutation and 1
°
for soft commutation, respec-
tively. In BLDC motor with trapezoidal type back-EMF, phase current waveforms look like step wave, which generates audi-
ble noise. In soft commutation mode (CNTL2 pin45 is LOW), the two phase currents overlap with some current slope. This
slope is determined by internal PWM pattern and external capacitor, CSOFT. The soft commutation using current slope of the
motor reduce acoustic noise and voltage spark which is generated on the motor coil at the commutation.
Spindle Output Driver
Spindle Output driver contains vertical PNP TR for high side and NPN TR for low side. For one commutation period, PNP TR
is controlled linearly by the difference between the current set point VCNT(pin1) and sensed current PCS (pin33), while NPN
TR is fully turned on. This scheme provides low voltage drop in linear current control application. The total voltage drop is
about 1.8V in 2A current rating. Maximum spindle current is defined as follows;
Where Rmetal is internal metal resistance(typically 50m
).
If R33 is 150m
,
the maximum spindle current is 2A.
Spindle Brake
There are two braking modes; internal and external braking. Spindle is braked when CNTL1 (pin44) is LOW by turning all
low side driver on. In case of power failure, brake power is supplied by charged capacitor connected CBRAKE (pin41). Gate
signal for two external MOSFET is issued from BRAKE (pin40) with time delay, which is defined by internal resistor (2.8M)
and external capacitor.
VDD
dissp&
sindicator
counter/logic
U
V
W
N
RPMSEL
F
ref
47
6
8
48
1
39
CLK
FG
READY
I
spindle
F
real
i
spll
i
spll
R33
C1b
C1a
R1
C39
s
1
s
2
33
Ispindle max
)
Rmetal
+
R33
-------------------------------------
=
相關PDF資料
PDF描述
FAN8623 12V Spindle Motor and Voice Coil Motor Driver(12V電源的主軸電機和語音線圈電機驅動器)
FAN8700 Camera Motor Drive and Control IC
FAN8702 6 Channel DSC Motor Driver
FAN8702B DUO-MODULAR TERM.WK 4/D2/2U/V0
FAN8702MP 6 Channel DSC Motor Driver
相關代理商/技術參數(shù)
參數(shù)描述
FAN8623 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Servo/Spindle Motor Controller/Driver
FAN8700 制造商:FAIRCHILD 制造商全稱:Fairchild Semiconductor 功能描述:Camera Motor Drive and Control IC
FAN8702 功能描述:馬達/運動/點火控制器和驅動器 6CH Motor Drive IC RoHS:否 制造商:STMicroelectronics 產品: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
FAN8702B 功能描述:馬達/運動/點火控制器和驅動器 DSC 1CH IC RoHS:否 制造商:STMicroelectronics 產品: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
FAN8702MP 制造商:FAIRCHILD 制造商全稱:Fairchild Semiconductor 功能描述:6 Channel DSC Motor Driver