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BD7905BFS
Optical disc ICs
6CH Power Driver for CD-ROM, DVD-ROM
BD7905BFS
BD7905BFS is a 6-channel driver IC that integrates all drivers necessary for optical disc driver. Low vibration, low noise, and low heat operation have been realized by adopting 180 PWM driving system for spindle motor driver. The built-in 2-channel sled motor driver is used for the stepping motor.
!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 and gain 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 180deg PWM drive. * Built in current limit, hall bias, short brake, FG 3-phase mixed signal output and reverse protection circuit. * Low ON-Resistor. (RON=0.85) 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 -40~+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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!Block diagram
SLRNF2
SLRNF1
SPCNF
SLO1+
SLO1-
SLO2+
SLO2-
AGND
SLVDD
SLIN2
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
29
28
67k
LEVEL SHIFT
-
-
SLIN1
+
FCO+
FCO-
LDO+
LDO-
TKO+
TKO-
DVCC
FCIN
TKIN
GND
GND
GND
GND
GND
AVM
VCC
47k
-
+
LEVEL SHIFT
LEVEL SHIFT
PRE LOGIC
PRE LOGIC FF LIMIT
47k
117.5k 117.5k
-
TSD
OSC
FF
67k
FG
REVERSE DETECT
HALL BIAS
1
HU+
2
HU-
3
HV+
4
HV-
5
HW+
6
HW-
7
HB
GND
GND
GND
GND
SPVM1
GND
V
PGND2
W
SPVM2
SPRNF
FG
CTL1
CTL2
SPIN
DGND
PGND1
LDIN
U
VC
+
+
47k
LIMIT
OSC Polarity COMP
Current LIMIT
188k PRE LOGIC FG 75k
- -
+ +
47k 112.5k
STBY/ BRAKE CONTROL
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
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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- 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 SPCNF 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 Spindle driver feedback filter Sled driver 2 negative output Sled driver 2 positive output Sled driver 1 negative output Sled driver 1 positive output BTL block and sled driver power 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
312.5
18 11 9 20
7
8 17
Hall signal input
54pin 54pin 54pin
Splindle driver feedback filter pin
FG signal output
54pin
54pin
1 3 5 2 4 6 33
21
10k
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
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
112.5k
Reference voltage input
51pin 10k 112.5k 50k
27
Control signal input
54pin 54pin 50k 50k
47k
10k
150k
50k
22 23
50k x3ch x2ch
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!Electrical characteristics (unless otherwise noted, Ta=25C, SLVDD=VCC=12V, DVCC=AVM=5V, VC=1.65V, SPRNF=0.22, 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
- - - - -
13 9 2.5 - 0.2
22 16 4.5 0.1 0.4
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
5 1.0 (0.50) - - 0.84 (0.42) -
30 1.3 (0.65) 1.8 0.8 1.0 (0.50) 100
55 1.6 (0.8) 2.3 1.4 1.16 (0.58) -
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 - 100 1
1.15
1.6
V A mVPP V
IHB=10mA
Fig1, 2
Spindle driver block Hall amplifier Input bias current 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 1 (one side) Input dead zone 2 (one side) Input output gain 1 Input output gain 2 Output ON resistor (upper) Output ON resistor (lower) Output limit current 1 Output limit current 2 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
VDZSP1 VDZSP2 gmSP1 gmSP2 RONUSP RONLSP ILIMSP1 ILIMSP2 fosc
0 0 1.2 (0.264) 170 (37.4) - - 1.2 (0.264) 300 (66.0) - - - -70 - - 17.7
10 30 1.5 (0.33) 245 (53.9) 0.6 0.25 1.5 (0.33) 440 (96.8) 100
40
mV
CTL1="H", CTL2="H"
Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2 Fig1, 2
120 mV CTL1="L", CTL2="H" 1.8 Arms/V Effective current (0.396) (Vrms/V) CTL1="H", CTL2="H" 320 mArms/V Effective current (70.4) (mVrms/V) CTL1="L", CTL2="H" 1.0 IL=500mA 0.5 1.8 (0.396) 580 (127.6) - - - A (V) mA (mV) kHz IL=-500mA CTL1="H", CTL2="H" CTL1="L", CTL2="H"
VFGH VFGL
4.9 0.1
V V
Fig1, 2 Fig1, 2
VOFFT VOHFT VOLFT GVFT
0 0.45 0.45 19.5
70 0.8 0.8 21.3
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
-100 - - 21.5
0 1.1 0.45 23.5 - -
100 1.4 0.8 25.5 - 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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!Measurement circuits
DVCC VINFC VINTK VCC
SLRNF2 SLRNF1
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- 0.01
SLED POWER SUPPLY UNIT
SLVDD
VINSL2 VINSL1
+
+
+
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
29
28
67k
LEVEL SHIFT
-
-
+
47k
-
+
LEVEL SHIFT
LEVEL SHIFT
PRE LOGIC
PRE LOGIC FF LIMIT
47k
117.5k 117.5k
-
TSD
OSC
FF
67k
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
LIMIT
OSC Polarity COMP
Current LIMIT
188k PRE LOGIC FG 75k
- -
+ +
47k 112.5k
STBY/ BRAKE CONTROL
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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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 (SL) =8+47H, RL (SP) =2+47H, RL (ACT, LD) =8, SLRNF=0.5, SPRNF=0.22, 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=VC5mV Check VSLRNF with output at VIN=VC55mV
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=0.22 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=230mV, VIN2=130mV VIN3=-130mV, VIN4=-230mV VSLRNF1 - VSLRNF2 ) / 0.5 230mV - 130mV VSLRNF4 - VSLRNF3 gm (-) = ( ) / 0.5 230mV - 130mV gm (+) = (
4 Spindle driver VIN1=300mV (gm1), 600mV (gm2) VIN2=100mV (gm1), 300mV (gm2) VIN3=-300mV (gm2), VIN4=-600mV (gm2) VSPRNF1 - VSPRNF2 ) / 0.22 300mV - 100mV VSPRNF1 - VSPRNF2 gm2 (+) = ( ) / 0.22 600mV - 300mV VSPRNF4 - VSPRNF3 gm2 (-) = ( ) / 0.22 600mV - 300mV gm1 (+) = (
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!Table of measure circuit switches position 2 (VCC=SPVM=SLVM=12V, DVCC=AVM=5V, VC=1.65V, RL (SL) =8+47H, RL (SP) =2+47H, RL (ACT, LD) =8, SLRNF=0.5, SPRNF=0.22, 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, H+=2.6V (2.4V)
IU+ (-), IV+ (-), IW+ (-)
Torque command VDZSP1 VDZSP2 gmSP1 gmSP2 RONUSP RONLSP ILIMSP1, 2 ILIMSP1, 2 fosc FG VFGH VFGL
3 3 4 4 3.3V 3.3V 3.3V 3.3V 1.85
H L H L H H H L H
H H H H H H H H H
2 2 2 2 1 1 2 2 2
1 1 1 1 2 2 1 1 1
1 1 1 1 1 1 1 1 1
1 1 1 1 2 2 1 1 1
3 Check VRNF with no output at VIN=VC Check VRNF with output at VIN=VC+40mV 3 Check VRNF with no output at VIN=VC Check VRNF with output at VIN=VC120mV
VSPRNF VSPRNF VSPRNF VSPRNF
See 10 of 17 See 10 of 17 ILSP=500mA ILSP=-500mA
RON = 12V - VOSP 0.5A RON = VOSP 0.5A
OUTU, V, W OUTU, V, W VSPRNF VSPRNF VOSPU
1.65V 1.65V
H H
H H
1 1
1 1
1 1
1 1
HU+=2.6V, HV+=2.4V, HW+=2.4V HU+=2.6V, HV+=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 Middle Sink Source Middle V Middle Source Sink Middle Sink Source W Sink Middle Source Source Middle 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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!Table of measure circuit switches position 3 (VCC=SPVM=SLVM=12V, DVCC=AVM=5V, VC=1.65V, RL (SL) =8+47H, RL (SP) =2+47H, RL (ACT, LD) =8, SLRNF=0.5, SPRNF=0.22, 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 and input output gain 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
Spindle
Sled
Focus
Tracking
Loading 1) 2)
... ON ... OFF
input output gain (spindle driver) 245mArms/V (Typ.) 1.5Arms/V (Typ.)
SPIN < VC Reverse-rotation braking mode Short-circuit braking mode 3) 4)
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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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-
INSP
VC
SOURCE
U
MID
SINK
SOURCE
V
MID
SINK
SOURCE
W
MID
SINK
ABCDEF ) Forward rotation mode
GH I
JKL ) Reverse protect ) Forward rotation torque
) Reverse rotation brake
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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 and larger than 100mVPP.
VCC VCC
HU HU HV HW HV HW
7pin Parallel connection
7pin Series connection
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 (CTL1="H") Input-output gain Output-limit current Gain with the added resistor 0.33/RNF (Arms/V) 0.33/RNF (A) 0.33x112.5k /{SPRNFx(Rin+112.5k)} (Arms/V) Spindle (CTL1="L") 53.9/RNF (mArms/V) 96.8/RNF (mA) 53.9x112.5k /{SPRNFx(Rin+112.5k)} (mArms/V) Sled 0.65/RNF (A/V) 0.5/RNF (A) 0.65x47k/ {SLRNFx(Rin+47k)} (A/V) Rin : added series resistor
5. PWM oscillation frequency The PWM oscillation for driving the spindle and sled is free running. The oscillating frequency is 100kHz (typ.).
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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. 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.
!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
67k
LEVEL SHIFT
-
-
+
47k
-
LEVEL SHIFT
LEVEL SHIFT
PRE LOGIC
PRE LOGIC FF LIMIT
+
47k
117.5k 117.5k
-
TSD
OSC
FF
67k
FG
REVERSE DETECT
HALL BIAS
1
2
3
4
5
6
7
HALL1
HALL2
HALL3
+
+
47k
LIMIT
OSC Polarity COMP
Current LIMIT
188k PRE LOGIC FG 75k
- -
+
+
47k 112.5k
STBY/ BRAKE CONTROL
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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BD7905BFS
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 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. (3) Filtering capacitor It is recommended to connect 0.01F filtering capacitor to SPCNF terminals. This capacitor filters PWM output carrier frequency. Dispersion of the cut off frequency due to circuit board wiring layout is taken into consideration. If it is difficult to filter at the recommended value due to circuit board wiring led round, the capacity can be increased. In this case, note that the output transmission delay time may be longer. (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
16/17
BD7905BFS
Optical disc ICs
!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.
17/17
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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