|
|
Part: FAN8621B
Category:
Power Management
-> Motor Controller/Drivers
-> DC Motor drivers/Controllers
-> DC Motor Drivers
Description: 12v Spindle Motor And Voice Coil Motor Driver ic
Company: Fairchild Semiconductor
Datasheet: Download FAN8621B datasheet File size : 400 kB
Request For quote: Find where to buy FAN8621B
Datasheet text preview:
www.fairchildsemi.com
FAN8621B
12V Spindle Motor and Voice Coil Motor Driver IC
Features
General
· · · · Hysteresis power on reset with delay function 5V, 12V supplies monitoring Thermal shut down(TSD) Programmable precision regulator usging minimal external component · Three state control input to reduce number of PINs
Description
The FAN8621B, is a Bipolar monolithic stand-alone IC, designed for 12V HDD applications.The internal power stage consists of vertical PNP and NPN TRs for both SPM and VCM, thus minimizing voltage drop, and increasing drive capability up to 2A for SPM and 1.2A for VCM. This device includes soft commutation drive to reduce audible noise and intelligent retract function for decreased bouncing.
Spindle Motor(SPM)
· · · · · · · · · · · ASIC based start-up Internal back-EMF processing Internal sensorless commutation Internal SPM speed control with SFLL(Syncronized Frequency Lock Loop). Linear SPM current control Selectable Motor Speed (5400/7200 RPM) Soft commutation circuitry to reduce acoustic noise Adjustable brake delay time Maximum 2A start-up current capability Internal and external spindle brake Speed lock indicator output 48-QFPH-1414
Voice Coil Motor (VCM)
· · · · · Intelligent retract (decreased bouncing) 1.2A internal VCM power driver Selectable transconductance 4V precision reference output Two PWM input (fine/coarse) for VCM set point
Typical Applications
· Hard disk drive(HDD)
Ordering Information
Device FAN8621B Package 48-QFPH-1414 Operating Temp. 0 ~ 70°C
Rev. 1.0.0 May. 2000.
©2000 Fairchild Semiconductor International
1
FAN8621B
Pin Assignments
B
2
FAN8621B
Pin Definitions
Pin Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Pin Name VCNT CSOFT ADJ SENSE5 V DD FG V REF C LK HALFVCC POR CDLY GAINSEL PWMH PWML CFVCM VCMREF4V CRET VCC FILO UT SENSE CRET2 PVCC VCMRRET SENSEOUT PGND VCM+ ERRIN VDD ERRO UT SUBGND W IO A A A A P O P I P O A I I I A P A P A A A P A A A P A A P A P A Pin Function Description Speed controller output. Range 3.8V to 0.5V Capacitor for soft commutation Adjust external regulator voltage (VREF) 5V power line sensing 5V power line Frequency generation for spindle rotation speed. Typically 1.08KHz (5400RPM) Regulator voltage output. This voltage is controlled by pin 3 voltage System clock. Digital clock input as a time reference 1/2 VCC Power on reset. H : normal, L: power fail Define POR delay time Sense amplifier gain selection. H : High gain (8), L : Low gain (2) Coarse PWM input for VCM set point Fine PWM input for VCM set point Output of PWM inputs to voltage converter 4V reference output for VCM Define retract delay time. 12V power line Filtered output of PWM inputs. This voltage define VCM set point Non-inverting input of differential amplifier for VCM current sensing Power for retract when power down 12V power line for VCM Negative output terminal of VCM power amplifier Adjust maximum retract current Output of differential amplifier for VCM current sensing Ground for VCM positive output terminal of VCM power amplifier Inverting input of VCM error amplifier 5V power line Output of VCM error amplifier Ground for spindle motor Spindle W phase output
3
FAN8621B
Pin Definitions (Continued)
Pin Number 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Pin Name PCS V SUBGND N U PVCC CCO M P BRAKE CBRAKE SENSE12 GND CNT L1 CNT L2 CNT L3 READY RPMSEL IO A A P A A P A A A A P I I I O I Pin Function Description Spindle current sensing. Spindle V phase output Ground for spindle Spindle N phase output Spindle U phase output 12V power line for spindle Current controller output. This Voltage define spindle output current Gating signal for external brake Charged back-EMF to supply brake power when power down 12V power line sensing Ground Control input for spindle . H: spindle enable, Z: Spindle bias enable, L: brake Start-up clock and soft commutation. H: Start-up clock , L : soft commutation. Control input for VCM. H: VCM enable, Z : VCM disable, L: retract Speed lock indicator when speed is within 0.7% speed error range. H : speed locked, L: unlocked Target spindle speed selection. L : 5400 rpm, H: 7200 rpm with 5MHz Clock
4
FAN8621B
Internal Block Diagram
CDLY
11 VCC
25K
POR
10 TSD
VREF
7
ADJ
3
VDD VDD VCC
5 29 18
VDD
7K
SENSE12 SENSE5
42 4
9K 11K
Power Management
Bandgap Reference & Bias
1.3V
Retract
External Brake
40 41 U V W N 38
BRAKE CBRAKE
U
FG
6
FG Generator
CSOFT
2
clock
Triangle Wave Generator
Back-EMF Processing & Zero Cross Detector
SPM Three Phase Power Driver
PVCC
36 37 Commutation Sequencing & Spindle Control 34 32 35 pre amp 31
N U V W SUBGND SUBGND CCOMP PCS PVCC VCM+
SPM bias enable
CNTL1 CNTL2 CNTL3
44 45 46
VCM on/off Retract
Three State Input Control
SPM output on start-up clock hard/soft Brake
VDD
FG
Real Speed
i spll
READY RPMSEL
47
48
Speed Discriminator & Speed Lock Indicator
Current Limiting
39 33 VCM H-bridge Power Driver VCMREF4V power amp VCC error amp
clock
22
Speed Reference
i spll
VCNT
27
1
CLK
8
Counter & Timing Control
9 power amp gain 14 26
HALFVCC
PWMH PWML CFVCM GAINSEL
13 14 15 12
PWMs Decorder & 2nd orderFilter
23
VCMPGND
U
V
W
Retract
VCMREF4V sense amp gain 2,8
VCM Gain Selection
Intelligent Retract
VCM+ SENSE
20
SENSE
VCMREF4V
16
VCMREF4V
43
21
24
17
19
28
30
25
GND
CRET2 RRET CRET FILOUT ERRIN
ERROUT
SENSEOUT
5
Others parts begin by fa
FA-1 FA-2 FA-3 FA-4 FA-5 FA-6 FA-7 FA-8 FA-9 FA-10 FA-11 FA-12 FA-13 FA-14 FA-15 FA-16 FA-17
|
|
|
