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BD7904FS
Optical disc ICs
5ch Power Driver for CD-ROM, DVD-ROM
BD7904FS
BD7904FS is a 5-channel driver IC that integrates all drivers and 3.3V regulator necessary for CD-ROM, and DVD-ROM systems into a single chip. Low head 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, 1channel PWM driver and 3phase motor driver. - ALL of the motor and actuator for CD-ROM, DVD-ROM etc. 2) ON/OFF for each driver, brake mode switching of spindle, and stand-by mode switching can be controlled by the two control terminals. 3) Built-in triangular-wave generator. 4) SSOP-A54 for strong head radiation. 5) Built in thermal-shut-down circuit. 6) FG 3phase synthetic output.
!Absolute maximum ratings (Ta=25C)
Parameter POWER MOS power suuply voltage Preblock/BTL powerblock power supply voltage PWM control block, REG power supply voltage Power dissipation Operating temperature range Storage temperature Symbol SPVM1,2,SLRNF 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 (10, 11, 18, 47, 48pin) is contained. 2 PCB (70mmx70mmx1.6mm glass epoxy) mounting. Reduced by 20.8mW for each increase in Ta of 1C over 25C.
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Optical disc ICs
!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, REG Power supply voltage Spindle output current SL/FO/TR/LO output current Symbol SPVM1, 2 SLRNF SLVDD, VCC AVM DVCC Iosp Ioo Min. - - AVM 4.3 4.3 - - Typ. VCC3 SLVDD3 12 5.0 5.0 1.0 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 SLRNF. 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.
!Block diagram
SLRNF
SLOPI
LDIN
54
53
52
51
50
49
48
47
46
45
44
VCC
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
OSC
LIMIT
FG
REVERSE DETECT
1
HU+
2
HU-
3
HV+
4
HV-
5
SPVM1
6
HW+
7
HW-
8
CTL1
9
CTL2
10
U
11
V
12
GND
13
GND
14
GND
15
GND
16
GND
17
PGND
18
W
19
VC
20
SPIN
SPRNF
HB
SPVM2
DGND
DVCC
REGOUT
REGNF
+
STBY/ BRAKE CONTROL
VC
-
HALL BIAS
21
22
23
24
25
-
+
+
-
Current COMP
FF
-
-
+
FF
-
-
FG
+
PRE LOGIC
LEVEL SHIFT
LEVEL SHIFT
LEVEL SHIFT
TSD
PWM OUT 3-phase MATRIX
OSC Polarity COMP
Current LIMIT
BG (1.3V)
-
+
26
-
-
+
+
27
REGGND
FCOPO
TKOPO
+
SLOPO
SLVDD
FCOPI
TKOPI
AGND
FCO+
FCO-
LDO+
LDO-
TKO+
TKO-
SLO+
SLO-
GND
GND
GND
GND
GND
AVM
FG
+
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!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- SPVM1 HW+ HW- CTL1 CTL2 U V GND GND GND GND GND PGND W VC SPIN SPRNF HB SPVM2 DGND DVCC REGOUT REGNF Function Hall amp. U positive input Hall amp. U negative input Hall amp. V positive input Hall amp. V negative input Spindle driver power supply 1 Hall amp. W positive input Hall amp. W negative input Driver logic control input 1 Driver logic control input 2 Spindle driver output U Spindle driver output V GND GND GND GND GND Spindle driver power ground Spindle driver output W Reference voltage input Spindle driver input Spindle driver current sense Hall bias Spindle driver power supply 2 PWM block pre-ground PWM block control power supply Regulator output voltage pin Regulator return pin 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 REGGND TKOPI TKOPO AVM FCOPI FCOPO FCO- FCO+ TKO- TKO+ AGND GND GND GND GND GND VCC LDO- LDO+ SLO- SLO+ SLVDD SLOPO SLOPI SLRNF LDIN FG Function Regulator block ground Tracking driver OP-AMP-input Tracking driver OP-AMP output Actuator driver block power supply Focus driver OP-AMP-input Focus driver OP-AMP output Focus driver negative output Focus driver positive output Tracking driver negative output Tracking driver positive output Ground GND GND GND GND GND BTL pre and Loading power supply Loading driver negative output Loading driver positive output Sled driver negative output Sled driver positive output Sled driver PowerMOS pre-supply Sled driver OP-AMP output Sled driver OP-AMP- input Sled driver current sense Loading driver input Frequency generator output
Positive/negative of the output terminals are determined in reference to those of the input terminals.
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Optical disc ICs
!Input output circuit
Three-phase motor driver output
23 5
Spindle driver current detection input
Hall bias
25pin
44pin
18
11
10
21
22
17
Hall signal input
25pin 25pin 25pin
FG signal output
25pin
1 3 6
2 4 7 54
PWM driver output SLED
52
BTL driver output FO, TK
BTL driver output LD
31pin 44pin 44pin 44pin
44pin 44pin
47
48
35 37
34 36
45
46
38
BTL driver input FO, TK
PWM driver input SLED1, 2
PWM driver input Spindle
44pin
49pin 25pin
25pin
44pin
49pin
20
29 32 51
x6 x5
VC
VC
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Optical disc ICs
Control signal reference voltage input PWM driver input LOADING
44pin 44pin 10k 15k 50k
19
44pin x2
53
50k
20k
VC
Regulator output
25pin x30 25pin 20k B.G.
26
Regulator REGNF terminal
25pin
25pin
27
51.5k
32.76k
28
Control signal input
25pin 25pin 50k 50k
8 9
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 Standby-on current 1 Standby-on current 2 Spindle driver block Hall bias Hall bias voltage Symbol Min. Typ. Max. Unit Conditions Circuit
IQ1 IQ2 IQ3 IST1 IST2
- - - - -
11 9.5 3.5 2.2 0.65
19 16 6.5 3.7 1.0
mA mA mA mA mA
VCC (Loading OFF) VCC (Loading ON) DVCC VCC DVCC
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
VHB
0.7 - 50 1
1.2
1.6
V A mVPP V
IHB=10mA
Fig1, 2 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 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 Sled driver block Input dead zone (one side) Input output gain Output ON resistor (upper) Output ON resistor (lower) Output limit current PWM frequency Actuator driver block Output offset voltage Output saturation voltage "H" Output saturation voltage "L" Voltage gain
VDZSP gmSP RONUSP RONLSL ILIMSL fosc
20 2.4 (0.8) - - 0.74 (0.24) - - -
50 3.0 (1.0) 0.6 0.35 0.95 (0.31) 100
90 3.6 (1.2) 1.0 0.7 1.16 (0.38) - - -
mV A/V (V/V) A (V) kHz
SPRNF=0.33 Ip=500mA Io=500mA SPRNF=0.33
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 Fig1, 2
VDZSL gmSL RONUSL RONLSL ILIMSL fosc
0 0.8 (0.4) - - 0.48 (0.24) - -50 - - 16.0
10 1.0 (0.5) 1.5 0.9 0.62 (0.31) 100
40 1.2 (0.6) 2.0 1.4 0.76 (0.38) -
mV A/V (V/V) A (V) kHz
Fig1, 2 SLRNF=0.5 Io=500mA Io=500mA SLRNF=0.5 Fig1, 2 Fig1, 2 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 Io=500mA Io=500mA
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
This product is not designed for protection against redioactive rays.
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Parameter Symbol Min. Typ. Max. Unit Conditions Circuit
Sled/Actuator driver pre-operational amplifier block Input offset voltage Input bias current Common mode input range Output source current Output sink current "H" level output voltage "L" level output voltage Loading driver block Output offset voltage Output saturation voltage "H" Output saturation voltage "L" Voltage gain Regulator block ROUT pin output voltage Peak output current Load regulation Line regulation CTL1, CTL2 Input high voltage Input low voltage Others VC drop-muting VCC drop-muting
VOFOP IBOP VICM IOSOOP IOSIOP VOHOP VOLOP
-6 - 0.4 0.3 3 11.5 (4.5) 0 -50 - - 16.0
0 20 - - - 11.9 (4.9) 0.1
6 300 10.8 (4.0) - - - 0.4
mV nA V mA mA V V ( ) : Sled block ( ) : Sled block
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
VOFLD VOHLD VOLLD GVLD
0 1.1 0.45 17.5
50 1.4 0.8 19.0
mV V V dB Io=500mA Io=500mA
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
VREG IorMax VRL VVCC
3.13 - - -
3.3 - 10 3 - -
3.47 500 30 10 - 0.5
V mA mV mV Ireg=100mA, VROUT=3.3V DVCC=4.5~5.5V
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
SLVM
VSLRNF
V
DVCC
SLRNF
2
SW-SL SL OUT-A1 LD OUT-A4 TK OUT-A3 FC OUT-A2
OUT+
OUT-
OUT+
OUT-
OUT+
OUT-
OUT+
OUT-
OUT
OUT
OUT
V
VFGH 100k
1
OPAMP A1
VCC
OPAMP A2
AVM
OPAMP A3
IN-
IN-
LDIN
+
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
29
IN-
28
OSC
LIMIT
FG
REVERSE DETECT
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
IU+ HU+
A
IV+ HV+
+
A
IW+ HW+
+
A
2 VRNF CTL1 CTL2
SW-SP 1 VC SPIN
+
V
RNF IHB DVCC
A
IU-
+
A
IV- H-
+
A
IW-
+
SPVM [ =VCC ]
U
V OUTSP
W
Fig.1
+
STBY/ BRAKE CONTROL
VC
-
HALL BIAS
21
22
23
24
25
IQDV
A
+
-
+
+
-
Current COMP
FF
-
-
+
FF
-
-
FG
+
PRE LOGIC
LEVEL SHIFT
LEVEL SHIFT
LEVEL SHIFT
TSD
PWM OUT 3-phase MATRIX
OSC Polarity COMP
Current LIMIT
BG (1.3V)
-
+
26
-
-
+
+
+ +
27
IReg
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Optical disc ICs
OPAMP
OPIN- SW-OP 2 1 30k IOP 30k
OPOUT
V V
VOOP VC
VOF
A
IOPB IN-
OUT+
V
47H RL
VO SW-RL 2 1
1 2 IL SW-IL
1 SW-IL
OUT-
OUT-A
2 IL
A2, A3, and A4 require no coil. (47H)
OUTSP U V W 2 1 RLSP SW-RL 2 1 2 1 3 SW-IL IL 47H
RLSP SW-RL RLSP
47H
47H
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 OP 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 1 1 1 1
1 Check VSLRNF with no output at VIN=VC Check VSLRNF with output at VIN=VC40mV
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
1 1 1 1 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
Iop...the peak current of Iosp or Iosl
Time
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 OP Conditions Measure point
Spindle driver block Hall bias VHB
1.65V
H
H
1
1
1
1
1
IHB=10mA
Pin 22
Hall amplifier IHIB
1.65V
H
H
1
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
1 1 1 1 1 1
2 Check VRNF with no output at VIN=VC20mV Check VRNF with output at VIN=VC90mV
VSPRNF VSPRNF OUTU, V, W OUTU, V, W VSPRNF VOSPU
See 10 of 18 previous page ILSP=500mA ILSP=-500mA
RON = 12V - VOSP 0.5A RON = VOSP 0.5A
1.65V 1.65V
H H
H H
1 1
1 1
1 1
1 1
1 1
HU+=2.6V, HV+=2.4V, HW+=2.4V HU+=2.6V, HV+=2.6V, HW+=2.4V
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 OP 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
1 1 1 1
VO
IL=500mA IL=-500mA 20log |(VO - VOFFT) / 0.25)|
5-OUT+ (-) OUT+ (-) VO
Loading driver block VOFLD VOHLD VOLLD GVLD
1.65V 3.3V (0V) 0V (3.3V) 0.25V - 1.65V - - 0V 5V - - - -
H H H H
L L L L
2 1 1 2
1 1 1 1
1 1 1 1
1 2 2 1
1 1 1 1
VO
IL=500mA IL=-500mA 20log |(VO - VOFFT) / 0.25)|
12-OUT+ (-) OUT+ (-) VO
Pre-operational amplifier block VOFOP IBOP IOSOOP IOSIOP VOHOP VOLOP Regulator block VREG IorMax VRL VVCC CTL1, CTL2 VIH VIL Others VMVC VMVCC H H H H H H H H 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Pin27 Pin27 H H H H H H H H H H H H 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 1 1 VOF IOPB
IOP=320A IOP=-4mA
VOF VOF VOOP VOOP
Ireg=100mA DVCC=4.5V~5.5V
Pin27 Pin27
1.65V 1.65V
L H
L H
2 2
1 1
1 1
1 1
1 1
Check active at "H"=2.0 Check stand-by at "L"=0.5
IQVC IQVC
1.65V 1.65V
H H
H H
1 1
1 1
1 1
1 1
1 1
Check all output at VC=0.7V Check all output at VCC=3.8V
OUTPUT OUTPUT
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Optical disc ICs
!Circuit operation 1. Driver control terminal 1 and 2 (pin 8 and pin 9) 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 (Pin8) L H - CTL2 (Pin9) L L H
... ON ... OFF
Spindle
Sled
Focus
Tracking
Loading
Regulator 1) 2)
CTL1 (Pin8) L H
CTL2 (Pin9) H H
SPIN > VC Forward-rotation mode Forward-rotation mode
SPIN < VC Reverse-rotation braking mode Short-circuit braking mode 3) 4)
1) Standby mode All blocks except for the regulator are standby-mode. 2) Drivers muting All the output channels except the loading are muted and there outputs are turn off. 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. 5) Regulator Regulator actives in all the mode.
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Optical disc ICs
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 4, 6, 7) and Hall bias (pin 22) (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
22pin Parallel connection
22pin Series connection
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Optical disc ICs
4. Torque command (spindle: pin 20, sled motor: pin 50) / output current detection terminals (spindle: pin 21, sled motor: pin 52) 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 0.3/RNF Sled 0.5/RNF 0.3/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. Regulator 3.3V is possible by connecting REGNF (27 pin) with REGOUT (26 pin). And, adjust by your inserting resistance when you use it in other voltage.
OUT1=BG{R1 (R2+R3+R4) +R2 (R3+R4)}/R2R4 OUT1 R1 R2 R3
+ - BG (1.3V)
R4
R3=51.5k R4=32.76k
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7. Muting functions a) VC-drop muting When the voltage at VC terminal (pin 19) 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 25) and VCC terminal (pin 44) drop to lower than 3.8V (typ.), the outputs of all the channels are turned off. The hysteresis voltage width is 80mV (typ.). 8. 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.
!Application example
SLVM=12V SLED IN FOCUS IN TRACKING IN
LOADING IN SLRNF
FG
SLED
LOADING
M
M
TRACKING VCC=12V
FOCUS 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
30
29
28
OSC
LIMIT
FG
REVERSE DETECT
1
2
3
4
5
6
7
8
9
SPINDLE
10
11
12
13
14
15
16
17
18
19
20
HALL1
HALL2
HALL3
-COM
-COM
VC SPINDLE IN REGOUT DVCC=5V
RNF
SPVM=12V
Fig.3
+
STBY/ BRAKE CONTROL
VC
-
HALL BIAS
21
22
23
24
25
-
+
+
-
Current COMP
FF
-
-
+
FF
-
-
FG
+
PRE LOGIC
LEVEL SHIFT
LEVEL SHIFT
LEVEL SHIFT
TSD
PWM OUT 3-phase MATRIX
OSC Polarity COMP
Current LIMIT
BG (1.3V)
-
+
26
-
+
-
+
+
+
27
17/18
BD7904FS
Optical disc ICs
!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 21) and the sled motor drive SLRNF (pin 52) 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 44) is used by the spindle and that applied to SLVDD (pin 49) by the sled. For this reason, be sure to apply VCC (pin 44) to the spindle and SLVDD (pin 49) to the sled according to the corresponding power supply voltages to prevent voltage differences. (3) Bypass capacitor Please connect a bypass capacitor (1F) across the supply voltage lines close to the IC pins. (4) 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.
18/18

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