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BD7902CFS
Optical disc ICs
6CH Power Driver for CD-ROM, DVD-ROM
BD7902CFS
BD7902CFS is a 6-channel driver IC that integrates all drivers necessary for CD-ROM, and DVD-ROM systems into a single chip. The built-in 2-channel sled motor driver is used for the stepping motor. Low heat operation can be achieved by applying the PWM driving system for sled and spindle motor drivers.
!Applications CD-ROM, DVD-ROM
!Features 1) 3channel BTL driver, 2channel PWM driver and 3phase motor driver. - ALL of the motor and actuator for CD-ROM, DVD-ROM etc. 2) These mode is able to be selected by the two control terminals. - ON/OFF of loading, and other 5channels, brake mode select of spindle driver and standby mode. 3) Built-in triangular-wave generator. 4) Package SSOP-A54 has large power dissipation. 5) Built in thermal-shut-down circuit. Spindle driver * Efficient drive by current feedback PWM drive. * Built in current limit, hall bias, short brake, FG output and reverse protection circuit. * Low ON-Resistor. (RON=0.95) Sled motor driver * Efficient drive by current feedback PWM drive. * Built in 2channel for stepping motor. Actuator driver, Loading driver * Linear BTL drive system.
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!Absolute maximum ratings (Ta=25C)
Parameter POWER MOS power suuply voltage Preblock/BTL powerblock power supply voltage PWM control block power supply voltage Power dissipation Operating temperature range Storage temperature Symbol SPVM1,2,SLRNF1,2 VCC,SLVDD,AVM DVCC Pd Topr Tstg Limits 151 15 7 2.62 -35~+85 -55~+150 Unit V V V W C C
1 POWER MOS output terminals (9, 11, 18, 34~37pin) is contained. 2 PCB (70mmx70mmx1.6mm glass epoxy) mounting. Reduced by 20.8mW for each increase in Ta of 1C over 25C.
!Recommended operating conditions (Ta=25C) (Set the power supply voltage taking allowable dissipation into considering)
Parameter POWER MOS Power supply voltage 1 POWER MOS Power supply voltage 2 Preblock Power supply voltage Power block Power supply voltage PWM control block Power supply voltage Spindle output current SL/FO/TR/LO output current Symbol SPVM1, 2 SLRNF1, 2 SLVDD, VCC AVM DVCC Iosp Ioo Min. - - AVM 4.3 4.3 - - Typ. VCC3 SLVDD3 12 5.0 5.0 1.2 0.5 Max. - - 14 VCC 6.0 2.54 0.8 Unit V V V V V A A
3 Set the same supply voltage to VCC and SPVM1, 2 to SLVDD and SLRNF1, 2. 4 The current is guaranteed 3.0A in case of the current is turned on/off in a duty-ratio of less than 1/10 with a maximum on-time of 5msec.
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Optical disc ICs
!Block diagram
SLRNF2
SLRNF1
SLGND
SLVDD
SLO1+
SLO1-
SLO2+
SLO2-
AGND
SLIN2
FCIN
TKIN
54
53
52
51
VCC
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
47k
29
28
47k
LEVEL SHIFT
-
-
SLIN1
+
FCO+
FCO-
LDO+
LDO-
TKO+
TKO-
DVCC
GND
GND
GND
GND
GND
AVM
47k
-
+
LEVEL SHIFT
LEVEL SHIFT
PRE LOGIC
PRE LOGIC FF LIMIT
47k
94k 94k
-
TSD
FF
47k
FG
REVERSE DETECT
HALL BIAS
1
HU+
2
HU-
3
HV+
4
HV-
5
HW+
6
HW-
7
HB
PGND1
SPVM1
V
GND
GND
GND
GND
GND
PGND2
SPVM2
FG
SPIN
DGND
SPRNF
CTL1
CTL2
LDIN
VC
U
W
+
+
47k
OSC
LIMIT
Current COMP
FF
PWM OUT 3-phase MATRIX
OSC Polarity COMP
Current LIMIT
94k 15k
- -
+ +
47k FG
STBY/ BRAKE CONTROL
15k
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
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Optical disc ICs
!Pin descriptions
Pin No. 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 Pin name HU+ HU- HV+ HV- HW+ HW- HB PGND1 U SPVM1 V GND GND GND GND GND PGND2 W SPVM2 SPRNF FG CTL1 CTL2 SPIN DGND LDIN VC Function Hall amp. U positive input Hall amp. U negative input Hall amp. V positive input Hall amp. V negative input Hall amp. W positive input Hall amp. W negative input Hall bias Spindle driver power ground 1 Spindle driver output U Spindle driver power supply 1 Spindle driver output V GND GND GND GND GND Spindle driver power ground 2 Spindle driver output W Spindle driver power supply 2 Spindle driver current sense Frequency generator output Driver logic control input 1 Driver logic control input 2 Spindle driver input PWM block pre-ground Loading driver input Reference voltage input Pin No. 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Pin name SLIN1 SLIN2 SLVDD SLRNF1 SLRNF2 SLGND SLO2- SLO2+ SLO1- SLO1+ AGND GND GND GND GND GND AVM FCO- FCO+ TKO- TKO+ LDO- LDO+ VCC TKIN FCIN DVCC Function Sled driver 1 input Sled driver 2 input Sled driver PowerMOS pre-supply Sled driver 1 current sense Sled driver 2 current sense Sled driver power ground Sled driver 2 negative output Sled driver 2 positive output Sled driver 1 negative output Sled driver 1 positive output Ground GND GND GND GND GND Actuator driver block power supply Focus driver negative output Focus driver positive output Tracking driver negative output Tracking driver positive output Loading driver negative output Loading driver positive output BTL pre and Loading power supply Tracking driver input Focus driver input PWM block control power supply
Positive/negative of the output terminals are determined in reference to those of the input terminals.
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!Input output circuit
Three-phase motor driver output
19 10
Spindle driver current detection input
51pin
Hall bias
54pin
18
11
9
20
7
17
Hall signal input
54pin 54pin 54pin
FG signal output
54pin
1 3 5
2 4 6 21
PWM driver output SLED1, 2
31 32
BTL driver output FO, TK
44pin 51pin 51pin 51pin
BTL driver output LD
51pin 51pin
34 36
35 37
45 47
46 48
49
50
33
BTL driver input FO, TK, LD
51pin
PWM driver input SLED1, 2
54pin
PWM driver input Spindle
54pin
51pin
30pin
54pin
26 52 53 28 24
47k
29
47k
15k
Control signal reference voltage input
51pin 10k 15k 50k
27 22
Control signal input
54pin 54pin 50k 50k
50k
23
50k
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!Electrical characteristics (unless otherwise noted, Ta=25C, SLVDD=VCC=12V, DVCC=AVM=5V, VC=1.65V, SPRNF=0.33, SLRNF=0.5)
Parameter Circuit current Quiescent current 1 Quiescent current 2 Quiescent current 3 Stanby-on current 1 Stanby-on current 2 Sled driver block Input dead zone (one side) Input output gain Output ON resistor (upper) Output ON resistor (lower) Output limit current PWM frequency Spindle driver block Hall bias Hall bias voltage Symbol Min. Typ. Max. Unit Conditions Circuit
IQ1 IQ2 IQ3 IST1 IST2
- - - - -
12 9 2.7 0.09 0
20 16 4.9 0.2 0.1
mA mA mA mA mA
VCC (Loading OFF) VCC (Loading ON) DVCC VCC DVCC
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
VDZSL gmSL RONUSL RONLSL ILIMSL fosc
15 0.8 (0.4) - - 0.8 (0.4) -
40 1.0 (0.5) 1.8 0.85 0.94 (0.47) 100
65 1.2 (0.6) 2.3 1.5 1.08 (0.54) -
mV A/V (V/V) A (V) kHz
Fig1, 2 SLRNF=0.5 IL=500mA IL=-500mA SLRNF=0.5 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
VHB
0.7 - 50 1
1.15
1.6
V A mVPP V
IHB=10mA
Fig1, 2
Spindle driver block Hall amplifier Input bias current Minimum input level Common mode input Range
IHIB VHIM VHICM
1 - -
5 - 4
Fig1, 2 Fig1, 2 Fig1, 2
Spindle driver block Torque control Input dead zone (one side) Input output gain Output ON resistor (upper) Output ON resistor (lower) Output limit current PWM frequency Spindle driver block FG output High voltage Low voltage Actuator driver block Output offset voltage Output saturation voltage "H" Output saturation voltage "L" Voltage gain
VDZSP gmSP RONUSP RONLSP ILIMSP fosc
20 2.4 (0.8) - - 1.2 (0.4) - - - -50 - - 16.0
50 3.0 (1.0) 0.6 0.35 1.42 (0.47) 100
90 3.6 (1.2) 1.0 0.7 1.64 (0.54) - - -
mV A/V (V/V) A (V) kHz
Fig1, 2 SPRNF=0.33 IL=500mA IL=-500mA SPRNF=0.33 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
VFGH VFGL
4.9 0.1
V V
100k pull up to DVCC
Fig1, 2 Fig1, 2
VOFFT VOHFT VOLFT GVFT
0 0.45 0.45 17.5
50 0.8 0.8 19.0
mV V V dB IL=500mA IL=-500mA
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
This product is not designed for protection against redioactive rays.
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Parameter Loading driver block Output offset voltage Output saturation voltage "H" Output saturation voltage "L" Voltage gain CTL1, CTL2 Input high voltage Input low voltage Others VC drop-muting VCC drop-muting Symbol Min. Typ. Max. Unit Conditions Circuit
VOFLD VOHLD VOLLD GVLD
-50 - - 16.0
0 1.1 0.45 17.5 - -
50 1.4 0.8 19.0 - 0.5
mV V V dB IL=500mA IL=-500mA
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
VIH VIL
2.0 -
V V
Fig1, 2 Fig1, 2
VMVC VMVCC
0.4 3.4
0.7 3.8
1.0 4.2
V V
Fig1, 2 Fig1, 2
This product is not designed for protection against radioactive rays.
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Optical disc ICs
!Measurement circuits
DVCC VINFC VINTK VCC
SLRNF2 SLRNF1
+
+
A
IQDV
A
IQVC
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
47k
SLVDD
LD OUT-A5
OUT+ OUT-
TK OUT-A4
OUT+ OUT-
FC OUT-A3
OUT+ OUT-
AVM
SL1 OUT-A1
OUT+ OUT-
SL2 OUT-A2
OUT+ OUT-
SLED POWER SUPPLY UNIT
VINSL2 VINSL1
29
28
47k
LEVEL SHIFT
-
-
+
47k
-
+
LEVEL SHIFT
LEVEL SHIFT
PRE LOGIC
PRE LOGIC FF LIMIT
47k
94k 94k
-
TSD
FF
47k
FG
REVERSE DETECT
HALL BIAS
1
IU+ HU+
2
IV+ HV+
3
4
IW+ HW+
5
6
7
A
+
A
+
A
+
IHB
A
IU-
+
A
IV-
+
A
IW- H-
+
+
+
47k
OSC
LIMIT
Current COMP
FF
PWM OUT 3-phase MATRIX
OSC Polarity COMP
Current LIMIT
94k 15k
- -
+ +
47k FG
STBY/ BRAKE CONTROL
15k
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
+
2 VSPRNF SW-SP VFG 1
100k CTL1 CTL2 VINSP DVCC VINLD VC
V
V
SPRNF SPVM
U
V OUTSP
W
Fig.1
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Optical disc ICs
SLED POWER SUPPLY
SLRNF2 SLRNF1 SLVDD
SW-SL VSLRNF1
SW-SL
V
VSLRNF2 SLRNF2
V
SLRNF1
SLVM
OUT+
V
47H RL
VO SW-RL 2 1
2 1 SW-IL IL IL
2 1 SW-IL
A3, A4 and A5 require no coil. (47H)
OUTSP U V W 2 1 RLSP SW-RL 2 1 2-V 2-U 2-W 47H
OUT-
OUT-A
RLSP SW-RL RLSP
47H
47H
1 SW-IL IL
Fig.2
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Optical disc ICs
!Table of measure circuit switches position 1 (VCC=SPVM=SLVM=12V, DVCC=AVM=5V, VC=1.65V, RL (act) =8, RL (SL) =8+47H, RL (SP) =2+47H, SLRNF=0.5, SPRNF=0.33, H-=2.5V, HU+=2.6V, HV+=HW+=2.4V)
Designation Circuit current IQ1 IQ2 IQ3 IST1 IST2 Sled driver block VDZSL gmSL RONUSL RONLSL ILIMSL fosc INPUT VIN CTL 1 2 SWITCH RL SP SL IL Conditions Measure point
- - - - -
L H L L L
H L H L L
1 1 1 1 1
1 1 1 1 1
1 1 1 1 1
1 1 1 1 1
1 Check VSLRNF with no output at VIN=VC15mV Check VSLRNF with output at VIN=VC65mV
IQVC IQVC IQDV IQVC IQDV
*1 *2 3.3V (0V) 0V (3.3V) 3.3V (0V) 1.45
H H H H H H
H H H H H H
2 2 1 1 2 2
1 1 1 1 1 1
1 1 2 2 1 1
1 1 2 2 1 1
VSLRNF VSLRNF
See bellow ILSL=500mA ILSL=-500mA
12V - VOSL + (-) RON= 0.5A RON= VOSL + (-) 0.5A
OUT+ (-) OUT+ (-) VSLRNF VOSL+
lop
Iosp Iosl VRNF1/RNF Iop
VRNF4/RNF
VRNF3/RNF
VRNF2/RNF SPRNF=0.33 SLRNF=0.5 VIN
Iosp or Iosl
VIN4
VIN3 Dead zone
VIN2
VIN1
Time Iop...the peak current of Iosp or Iosl
2 Sled driver VIN1=240mV, VIN2=140mV VIN3=-140mV, VIN=-240mV gm (+) = ( VSLRNF1 - VSLRNF2 ) / 0.5 240mV - 140mV VSLRNF4 - VSLRNF3 gm (-) = ( ) / 0.5 240mV - 140mV
4 Spindle driver VIN1=150mV, VIN2=100mV VIN3=-100mV, VIN=-150mV VSPRNF1 - VSPRNF2 ) / 0.33 150mV - 100mV VSPRNF4 - VSPRNF3 gm (-) = ( ) / 0.33 150mV - 100mV gm (+) = (
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Optical disc ICs
!Table of measure circuit switches position 2 (VCC=SPVM=SLVM=12V, DVCC=AVM=5V, VC=1.65V, RL (act) =8, RL (SL) =8+47H, RL (SP) =2+47H, SLRNF=0.5, SPRNF=0.33, H-=2.5V, HU+=2.6V, HV+=HW+=2.4V)
Designation INPUT VIN CTL 1 2 SWITCH RL SP SL IL Conditions Measure point
Spindle driver block Hall bias VHB
1.65V
H
H
1
1
1
1
IHB=10mA
Pin 7
Hall amplifier IHIB
1.65V
H
H
1
1
1
1
Current flowing in each terminal at H-=2.5V, HW+=2.7V (2.3V), HV=2.5V
IU+ (-), IV+ (-), IW+ (-)
Torque command VDZSP gmSP RONUSP RONLSP ILIMSP fosc FG VFGH VFGL
3 4 3.3V 3.3V 3.3V 1.85
L L H H H H
H H H H H H
2 2 1 1 2 2
1 1 2 2 1 1
1 1 1 1 1 1
1 1 2 2 1 1
2 Check VRNF with no output at VIN=VC20mV Check VRNF with output at VIN=VC90mV
VSPRNF VSPRNF
See 15 of 20 ILSP=500mA ILSP=-500mA
RON = 12V - VOSP 0.5A RON = VOSP 0.5A
OUTU, V, W OUTU, V, W VSPRNF VOSPU
1.65V 1.65V
H H
H H
1 1
1 1
1 1
1 1
HW+=2.4V HW+=2.6V
VFG VFG
5 Condition of input HU+ 2.4V 2.6V 2.6V 2.6V 2.4V 2.4V HV+ 2.6V 2.4V 2.6V 2.4V 2.6V 2.4V HW+ 2.6V 2.6V 2.4V 2.4V 2.4V 2.6V U Source Sink Hi-Z Sink Source Hi-Z V Hi-Z Source Sink Hi-Z Sink Source W Sink Hi-Z Source Source Hi-Z Sink Condition IOSPU=500mA IOSPV=500mA IOSPW=500mA IOSPU=-500mA IOSPV=-500mA IOSPW=-500mA Measure point VOSPU VOSPV VOSPW VOSPU VOSPV VOSPW
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Optical disc ICs
!Table of measure circuit switches position 3 (VCC=SPVM=SLVM=12V, DVCC=AVM=5V, VC=1.65V, RL (act) =8, RL (SL) =8+47H, RL (SP) =2+47H, SLRNF=0.5, SPRNF=0.33, H-=2.5V, HU+=2.6V, HV+=HW+=2.4V)
Designation INPUT VIN CTL 1 2 SWITCH RL SP SL IL Conditions Measure point
Actuator driver block VOFFT VOHFT VOLFT GVFT
1.65V 3.3V (0V) 0V (3.3V) 0.25V
H H H H
H H H H
2 1 1 2
1 1 1 1
1 1 1 1
1 2 2 1
VO
IL=500mA IL=-500mA 20log |(VO - VOFFT) / 0.25)|
5-OUT+ (-) OUT+ (-) VO
Loading driver block VOFLD VOHLD VOLLD GVLD CTL1, CTL2 VIH VIL CTL1, CTL2 VMVC VMVCC
1.65V 3.3V (0V) 0V (3.3V) 0.25V 1.65V 1.65V
H H H H
L L L L
2 1 1 2
1 1 1 1
1 1 1 1
1 2 2 1
VO
IL=500mA IL=-500mA 20log |(VO - VOFFT) / 0.25)| Check active at "H"=2.0 Check stand-by at "L"=0.5
12-OUT+ (-) OUT+ (-) VO
L H
L H
2 2
1 1
1 1
1 1
IQVC IQVC
1.65V 1.65V
H H
H H
1 1
1 1
1 1
1 1
Check all output at VC=0.7V Check all output at VCC=3.8V
OUTPUT OUTPUT
!Circuit operation 1. Driver control terminal 1 and 2 (pin22 and pin23) All the drivers and spindle-drive braking mode can be switched on/off by inputting combinations of H-level signal (higher than 2V) and L-level signal (lower than 0.5V) to these terminals.
CTL1 (Pin22) L H - CTL1 (Pin22) L H CTL2 (Pin23) L L H CTL2 (Pin23) H H SPIN > VC Forward-rotation mode Forward-rotation mode SPIN < VC Reverse-rotation braking mode Short-circuit braking mode 3) 4) Spindle Sled Focus Tracking Loading 1) 2)
... ON ... OFF
1) Standby mode The IC is brought into standby state, and its power dissipation can be limited. 2) Drivers muting All the output channels except the loading are muted and their outputs are turn off.
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Optical disc ICs
3) Reverse-rotation braking mode (spindle) A reverse-rotation torque is applied when SPIN < VC. Reverse-rotation is detected with SPIN input and Hall input. If the spindle detects reverse rotation when SPIN < VC, all the outputs are shorted out to GND. 4) Short-circuit braking mode (spindle) All the spindle driver outputs are shorted out to GND when SPIN < VC. 2. Input/output timing chart
HU+
HU-
FWD
FWD
REV
FWD
HV+
HV-
HW+
HW-
SPIN
Vref
SOURCE
U
Hi-Z
SINK
SOURCE
V
Hi-Z
SINK
SOURCE
W
Hi-Z
SINK
ABCDEF ) Forward rotation mode
GH I
JKL ) Reverse protect ) Short brake
) Reverse rotation brake
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Optical disc ICs
) Forward-rotation mode In this mode, the disc rotation is started and accelerated. When forward-rotation signal inputs from the Hall elements to the positive spindle-drive input terminals (SPIN > VC), the spindle-drive output terminals output forward torque signal.
Hall amplifier input (forward rotation) HU+ A B C D E F L L L H H H HU- H H H L L L HV+ L H H H L L HV- H L L L H H HW+ H H L L L H HW- L L H H H L U Hi-Z Source Source Hi-Z Sink Sink SPIN > VC V Source Hi-Z Sink Sink Hi-Z Source W Sink Sink Hi-Z Source Source Hi-Z Source=PWM
, ) Braking mode In this mode, the disc rotation is decelerated and stopped. Reverse-rotation braking When the forward-rotation signal inputs from the Hall elements to the negative spindle-drive input terminals (SPIN < VC), the spindle-drive output terminals output reverse torque signal.
Hall amplifier input (forward rotation) HU+ G H I J K L L L L H H H HU- H H H L L L HV+ L H H H L L HV- H L L L H H HW+ H H L L L H HW- L L H H H L U Hi-Z Sink Sink Hi-Z Source Source SPIN < VC V Sink Hi-Z Source Source Hi-Z Sink W Source Source Hi-Z Sink Sink Hi-Z Source=PWM
3. Hall inputs (pin 1 to 6) and Hall bias (pin 7) (Spindle) Hall elements can be connected either in series or in parallel. Set the Hall input voltage to 1.0 to 4.0V.
VCC VCC
HU HU HV HW HV HW
7pin Parallel connection
7pin Series connection
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Optical disc ICs
4. Torque command (spindle: pin 24, sled motor: pin 28 and 29) / output current detection terminals (spindle: pin 20, sled motor: pin 31 and 32) The relation between the torque command input and the output current detection terminals input is expressed as shown below:
SPRNF SLRNF
FWD rotation
Dead zone + Dead zone -
VC
SPIN SLIN1, 2
The input-output gain (gm) and the output-limit current (ILIM) depend on the resistance of RNF (output current detection resistor). Please refer to the following expression. The gain to drive the spindle or the sled motor can be decreased by connecting a resistor in series to each input terminal.
Gain expression
Spindle Input-output gain gm (A/V) Output-limit current Ilim (A) 1.0/RNF 0.47/RNF Sled 0.5/RNF 0.47/RNF 0.5x47k/{SLRNFx(Rin+47k)} Rin : added series resistor
Gain with the added resistor gm (A/V) 15k/{SPRNFx(Rin+15k)}
5. PWM oscillation frequency The PWM oscillation for driving the spindle and sled is free running. The oscillating frequency is 100kHz (typ.). 6. Muting functions a) VC-drop muting When the voltage at VC terminal (pin 27) drops to a value lower than 0.7V (typ.), the outputs of all the channels are turned off. Set the VC terminal voltage to larger than 1.0V. b) VCC-drop muting When the voltages at DVCC terminal (pin 54) and VCC terminal (pin 51) drop to lower than 3.8V (typ.), the outputs of all the channels are turned off. c) Over voltage protection circuit When the voltages at VCC terminal (pin 51) drop to uper than 15.5V (typ.), the output of only the spindle block is turned off. 7. Thermal-shutdown A thermal-shutdown circuit (over-temperature protection circuit) is built in to prevent the IC from thermal breakdown. Use the IC under the thermal loss allowed to the package. In case the IC is left running over the allowable loss, the junction temperature rises, and the thermal-shutdown circuit works at the junction temperature of 175C (typ.) (the outputs of all the channels are turned off). When the junction temperature drops to 150C (typ.), the IC start operating again.
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!Application example
TRACKING FOCUS IN IN VCC=12V
STM
TRACKING LOADING
FOCUS
SLVM=12V SLED SLED IN2 IN1
DVCC=5V
SLRNF2
M
AVM=5V
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
SLRNF1
SLED1
SLED2
30
47k
29
28
47k
LEVEL SHIFT
-
-
+
47k
-
LEVEL SHIFT
LEVEL SHIFT
PRE LOGIC
PRE LOGIC FF LIMIT
+
47k
94k 94k
-
TSD
FF
47k
FG
REVERSE DETECT
HALL BIAS
1
2
3
4
5
6
7
HALL1
HALL2
HALL3
!Operation notes (1) Wiring for SPRNF and SLRNF Considering the wiring resistance, connect each detecting resistor as close as possible to the current detection terminals for the spindle drive SPRNF (pin 20) and the sled motor drive SLRNF 1 and 2 (pin 31 and 32) of the IC. (2) Current detection reference voltage The detection of current in the spindle and sled involves the detection of voltage between the detection resistances, but as the reference voltage of internal circuit, the voltage applied to VCC (pin 51) is used by the spindle and that applied to SLVDD (pin 30) by the sled. For this reason, be sure to apply VCC (pin 51) to the spindle and SLVDD (pin 30) to the sled according to the corresponding power supply voltages to prevent voltage differences.
+
+
47k
OSC
LIMIT
Current COMP
FF
PWM OUT 3-phase MATRIX
OSC Polarity COMP
Current LIMIT
94k 15k
- -
+
+
47k FG
STBY/ BRAKE CONTROL
15k
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
FG
23
24
25
26
27
SPINDLE 5V SPRNF
-COM
-COM SPINDLE IN LOADING IN
VC
SPVM=12V
Fig.3
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BD7902CFS
Optical disc ICs
(3) Reverse-rotation braking In the case of reverse-rotation braking from high speed rotation, pay good attention to reverse electromotive force. Furthermore, fully check the voltage to be applied to the output terminal and consider the revolutions applied to the reverse-rotation brake. (4) Bypass capacitor Please connect a bypass capacitor (0.1F) across the supply voltage lines close to the IC pins. (5) Supply fault, ground fault, and short-circuit between output terminals Do not short-circuit between any output pin and supply pin (supply fault) or ground (ground fault), or between any output pins (load short-circuit). When mounting the IC on the circuit board, be extremely cautions about the orientation of the IC. If the orientation is mistaken, the IC may break down, and produce smoke in some cases.
!Electrical characteristic curves
POWER DISSIPATION : Pd (W)
3 2.6W
2
1
0
0
25
50
75
100
125
150
AMBIENT TEMPERATURE : Ta (C)
On less than 25.7% (percentage occupied by copper foil), 70x70mm2, t=1.6mm glass epoxy mounting.
Fig.4 Power dissipation
!External dimensions (Units : mm)
22.00.2
54 28
13.40.3 11.40.2
4.00.2
1
27
2.20.1
6.00.2
0.150.1
0.1
0.8
0.360.1
0.1
SSOP-A54
0.3Min.
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Appendix
Notes
No technical content pages of this document may be reproduced in any form or transmitted by any means without prior permission of ROHM CO.,LTD. The contents described herein are subject to change without notice. The specifications for the product described in this document are for reference only. Upon actual use, therefore, please request that specifications to be separately delivered. Application circuit diagrams and circuit constants contained herein are shown as examples of standard use and operation. Please pay careful attention to the peripheral conditions when designing circuits and deciding upon circuit constants in the set. Any data, including, but not limited to application circuit diagrams information, described herein are intended only as illustrations of such devices and not as the specifications for such devices. ROHM CO.,LTD. disclaims any warranty that any use of such devices shall be free from infringement of any third party's intellectual property rights or other proprietary rights, and further, assumes no liability of whatsoever nature in the event of any such infringement, or arising from or connected with or related to the use of such devices. Upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or otherwise dispose of the same, no express or implied right or license to practice or commercially exploit any intellectual property rights or other proprietary rights owned or controlled by ROHM CO., LTD. is granted to any such buyer. Products listed in this document use silicon as a basic material. Products listed in this document are no antiradiation design.
The products listed in this document are designed to be used with ordinary electronic equipment or devices (such as audio visual equipment, office-automation equipment, communications devices, electrical appliances and electronic toys). Should you intend to use these products with equipment or devices which require an extremely high level of reliability and the malfunction of with would directly endanger human life (such as medical instruments, transportation equipment, aerospace machinery, nuclear-reactor controllers, fuel controllers and other safety devices), please be sure to consult with our sales representative in advance. About Export Control Order in Japan Products described herein are the objects of controlled goods in Annex 1 (Item 16) of Export Trade Control Order in Japan. In case of export from Japan, please confirm if it applies to "objective" criteria or an "informed" (by MITI clause) on the basis of "catch all controls for Non-Proliferation of Weapons of Mass Destruction.
Appendix1-Rev1.0

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