Mitsubishi M56785FP Datasheet

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

DESCRIPTION

The M56785FP is a semiconductor integrated circuit in order to
drive the spindle motor.

FEATURES

●Large power dissipation (Power Package).

●3.3V DSP available.

●The supply voltage with wide range.

●High motor drive current .

●Low saturation voltage. (typical 1.2V at load current 500mA)

●Motor current control for both motor torque directions.

●Reverse torque mode select [SHORT BRAKING,etc].

●Sleep mode. (Zero total current )

●Hall amplifier sensitivity select.

(Minimum voltage : 35mVp-p or 50mVp-p)

●FG signal output terminal.

●Automatic stop select. (Removable function)

●Reverse detected signal pin.

APPLICATION

CD-ROM,DVD,DVD-ROM,DVD-RAM etc.

PIN CONFIGURATION (TOP VIEW)

N.C

S/S

RDS

FG

MODE2
MODE1

GND

VM

CC2

V

EC
ECR
VCC1

HB

N.C

1
2
3
4

CI

7
8

M56785FP

13
14
15 28
16
17
18
19
20
21

Outline 42P9R-A

N.C

42

W

41

V

40

U

39

RS

385

MODE3

376

MODE4

36
35
349
3310
3211

GND

3112
30
29

Hw­Hw+

27

Hv-

26

Hv+

25

Hu-

24

Hu+

23

N.C

22

N.C: no connection

BLOCK DIAGRAM

15

VM

VCC2

16

FG

RDS

7

6

36

37

4

3

BRAKING
MODE
CHANGE

SENSE

FG
RDS

MODE1

MODE2

MODE4

MODE3

UV

39 40 41

120°

MATRIX

+ -+-+-

23

24 25 26 27 28

Hv+ Hv-

Hu-

Hu+

W

Hw+

Hw-

S/S

2 38

I / I

Converter

TSD

Hall
Bias

5

HB

CI

S

R

-

+
+

1720

EC ECR

Vref

V/I Converter

18

VCC1

19

8 to 14 29 to 35

GND

GND

PIN DESCRIPTIO N

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

Pin No. Symbol Function

1
2
3
4
5
6
7

N.C
S/S
RDS
FG

I

C

Reverse detected signal
Frequency generator output
Phase Compensation

MODE1 Reverse torque mode select 1
GND GNDGND GND

15
16
17
18
19
20
21

CC2 12V supply voltage MODE3 Automatic stop select

V
EC R

V

CC1 V5V supply voltage Motor drive output V

Bias for Hall SensorHB W Motor drive output W

N.C N.C

* Pull-up resistors (10kohm) are included in the circuits connected to pin [RDS] and pin[FG].

Pin No. Symbol Function

22
23
24
25
26
27
28

29 –358 –14

36
37
38
39
40
41
42

N.C

Hu+ Sensor amp. inputHu+Start / Stop
Hu- Hu- Sensor amp. input
Hv+ Hv+ Sensor amp. input
Hv- Hv- Sensor amp. input
Hw+ Hw+ Sensor amp. inputMODE2 Reverse torque mode select 2
Hw- Hw- Sensor amp. input

Hall amplifier sensitivity selectVM Motor supply voltage MODE4

SMotor speed control Motor current sense

U Motor drive output UECR The reference voltage for EC

43

ABSOLUTE MAXIMUM RATING (Ta=25 )

Symbol Rating UnitParameter Conditions

VCC2 12V supply voltage 16 pin 16

CC1 5V supply voltage V7.019 pin

V
Io Output current 1.5 ANote 1

Sensor amp.
Differential input range

Pt Power dissipation W1.2Free Air
Kθ

Thermal derating mW/˚CFree Air 9.6
Tj Junction temperature
Topr Operating temperature -20 +75
Tstg Storage temperature

23 –28

pins

16 V15 pinVM Motor supply voltage

150

–

–

V

V4.5VH(c)

˚C
˚C
˚C-40 +125

*Note1 ; The ICs must be operated within the Pt (power dissipation) or the area of safety operation

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

RECOMMENDED OPERATING CONDITIONS

Symbol Parameter

Min. Typ. Max.

5V Power supply V5.04.5 5.5VCC1

ELECTRICAL CHARACTERISTICS (VCC=5V, VCC2=12V, VM=12V, Ta=25˚C unless otherwise noted.)

Symbol Parameter

Icc1

Icc2

Sleep Mode Supply
current- 1

Sleep Mode Supply
current- 2

Supply current- 3Icc3 pin Input Current (EC=ECR=2.5V) [ pin High] 6.0 mA
Vsat Saturation voltage
ECdead-

ECdead+
ECR pin [3.3v DSP available] 1.65 V0.5 4.0

EC

Dead Zone Control

voltage dead zone

Reference voltage

Input range

Control voltage Input

range

15 16 2

and pin total Input Current ( pin low or open) 0 100

19 2

pin Input Current ( pin low or open) 500

19

Top and Bottom saturation voltage.
(Load current :500mA)

EC < ECR
EC > ECR

18

17

pin [3.3v DSP available] 0.5 4.0 V

Gio Control gain Io = Gio / Rsense [A/V] 0.3 V/V0.350.25
Vlim Control limit Ilim = Vlim / Rsense [A] 0.3 0.330.27 V

VH com

Hall sensor amp

common mode input

23 – 28

pins

range
VHmin1

VHmin2 MODE4=GND 35
VHb

Hall sensor amp.

input signal revel

Hall bias terminal

output voltage

23 – 28

pins

Load current (IHb) =10 mA. V0.85 1.20.6

Hall bias terminal sink

current

2

Von

Motor start voltage

pin input voltage when it starts up the motor.
*The IC is in the active condition.
*The hall bias is available.

2

Voff

Motor stop voltage

pin input voltage when it stops the motor.
*The IC is in the sleep condition.
*The hall bias is off.

7 6 37

V

ViL

iH

mode pin input high
voltage

mode pin input low
voltage

pin[MODE1], pin[MODE2], pin[MODE3]

36

and pin[MODE4] input voltage
when they are HIGH.

7 6 37

pin[MODE1], pin[MODE2], pin[MODE3]

36

and pin[MODE4] input voltage
when they are LOW.

V

OL

3pin[RDS],4pin[FG]
output low voltage

Io current = 1mA 0.5 V

Conditions

2

MODE4=OPEN or HIGH

Limits

12.04.5VCC2 12V Power supply 13.2 V

Limits

Min. Typ. Max.

1.2 1.9 V

-40 -21 0
+400 +21

1.65

1.2 4.5 V

50

30IHb

2.0

0.8

2.0

0.8

Unit

V12.04.5 13.2Motor Power supplyVM

mA700Io Output drive current

Unit

µA

µA

mV

mV
p-p

mA

V

V

V

V

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

ELECTRICAL CHARACTERISTICS (VCC1=5V, VCC2=12V, VM=12V, Ta=25˚C Unless otherwise noted. )

Reverse Torque

Current limit

0 – +40mV

0

0.6A/V

0 – -40mV

Current limit

Forward Torque

Figure 1. The characteristics of the control voltage

and motor current ( Torque ).

0.6A/V

The relationship between the EC-ECR (the difference
between EC<(control voltage> and ECR <reference
voltage> ) and the torque is shown in Figure 1.
The current gain is 0.6A/V (at sensing resistor :0.5ohm)
in both torque directions, and the dead zone is from
±0mV to ±40mV.
When the all short brake mode is selected, the coil
current under the reverse torque control depends on
the back emf. and the coil resistance.

EC - ECR

THERMAL DERATING

6.0
(W)

5.0

4.0

3.0

2.0

Power Dissipation (Pdp)

1.0

0 25 50 75 100 125

4.0W
using A-type board

3.0W
using B-type board

2.7W
using C-type board

Ambient Temperature Ta ( )

This IC's package is POWER-SSOP, so improving
the board on which the IC is mounted enables a
large power dissipation without a heat sink.
For example, using an 1 layer glass epoxy resin
board, the IC's power dissipation is 2.7W at least.
And it comes to 4.0W by using an improved 2 layer
board.
The information of the H, I, J type board is shown
in the board information.

150

HALL AMPLIFIER INPUT AND COMMUTATION

The relationship between the hall amplifier inputs voltage and the
motor current outputs is shown in Figure 2.

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

Hu+Hv+Hw+

Hall
inputs

Output
current

U WV

V

SOURSE

UVWU

W

Figure 2.

HALL AMPLIFIER INPUT SENSITIVITY SELECT

MODE4

OPEN or HIGH GND

120 degree switching

120 degree
soft switching

** Io current

changes sharply.

SINK

Hall elements

W

V

V

W

U

U

FORWARD

EC<ECR

U

Outer loator

W

V

U

W

V

REVERSE

EC>ECR

Figure 3 shows the hall amplifier input sensitivity select function. You are
able to select a sensitivity of a hall amplifier out of two levels which is
suitable for the hall elements type.
If the output minimum level of the hall elements is lower than 50mVp-p,
please connect the MODE4 pin to external GND. In this case, the
output current changes shaply. If the output minimum level of the hall
elements is higher than 50mVp-p, please make the MODE4 pin open,
then the output current is commutated softly.
We recommend that the output level of the hall elements be set between
80mVp-p and 120mVp-p, and the MODE4 pin is an open.

The hallamp
minimum input voltage

The hallamp
minimum input voltage

is 50 mVp-p.

Figure 3.

SLEEP MODE FUNCTION

START / STOP ( pin)

LOW or OPEN HIGH

Motor Stop

Bias off

Hall-Bias of

Figure 4.

2

Motor on

Bias on

Hall-Bias on

is 35 mVp-p.

Figure 4 shows the sleep mode function. If the pin [S/S] is set to be

2

open or low, the motor drive outputs have high impedance and the motor
stops. Then, the IC bias current wil be a slight current (please refer to the
electrical characteristics), and the hall bias output will be cut off. When
the pin input is high, all the circuits will work.2

FORWARD AND REVERSE ROTATION DETECT
FUNCTION

Figure 5 shows the circuits and the functions of the forward and
reverse rotation detect .
The output of the RDS pin is determined by the signals of hall
inputs ( Hu+, Hu-, Hv+ and Hv- ) which indicate the direction of
rotation. When the motor is spinning forward, the RDS pin output
will be low. When the motor rotates reversely in stop mode, it will
be high.
The RDS pin is pulled-up to VCC1 by internal resistor (typ.10kohm).

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

RDS FG

VCC1

RDS

FG

MODE3

CI

FORWARD

D

T

Q

High

Low

High

Low

VCC1

Q

Q

D

R

FG-amp

T

Hu+Hv+Hw+

EC-ECR

Comparator
Hysteresis

RDS

FG

+

-

+

-

REVERSE

D
T

Q

High

Low

High

Low

Hu+ Hu- Hv+ Hv- Hw+

Hall sensor-amp

Hv+

Hu+Hw+

Hw-

Figure 5.

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

AUTOMATICALY STOP AFTER REVERSE
BRAKING FUNCTION

Figure 5 also shows the automaticaly stop (after the reverse
braking) circuit. Figure 6 is its function table which shows whether
the automaticaly stop function is on or off, and its state is
determined by MODE3 input.
When the MODE3 is open or high, the motor will stop rotating
automaticaly after the reverse braking.
When the MODE3 is low or connected to GND, the motor will
continue the reverse rotation. This function is useful for the case
that the system doesn't require the automaticaly stop function, and
in the system a motor receives a stop command from the outside
of this IC. For example, a µcom can detect the reverse rotation
from the RDS pin output, and can control all the torque of a motor.
So it can stop the motor outside this IC.

FG FUNCTION

Figure 5 also shows the circuits and the functions of the frequency
generator. The FG pin outputs the square pulse signal
synchronizing with the hall inputs [Hv+ and Hv-] timming .
The FG pin is pulled-up to V
10Kohm].

MODE3

OPEN or HIGH GND

AUTOMATIC

STOP

Figure 6.

CC1 by an internal resistor [typ.

UN-AUTOMATIC
(NON-STOP)

REVERSE TORQUE MODE SELECT FUNCTION

In the 4 times speed and the 6 times speed CDROM drive
system, the reverse braking style has been used for a
deceleration of the rotation speed. However, i n the CDROM
drive system above an 8 times speed, the motor current above

0.5A is needed, because a high speed access time are required
for motor driver ICs. If the reverse braking is used at 0.5A, the
IC junction temperature will be too much high, and the heat loss
of the IC will be large.
Therefore, this motor driver has the braking mode select
function (REVERSE BRAKING MODE and SHORT BRAKING
MODE). The breaking mode can be determined by the external
logic signals synchronizing with servo timing, and it can make a
heat loss of the IC smaller by adjusting the junction
temperature.
Figure 7 shows the reverse torque mode select function table. If
you want the former braking style (the reverse braking ), please
select only the REVERSE BRAKING mode [MODE1=LOW or
OPEN and MODE2=HIGH]. But the heat loss will be larger, and
sometimes external heat sink would be necessary.
If it is possible to get ports more than two from µcom, you can
flexibly control the four kinds of BRAKING MODE. So the heat
loss can be half as usual. For example, the REVERSE
BRAKING MODE is on under the CLV control, and the ALL
SHORT BRAKING MODE is for seeking. When the motor
should be stopped, the ALL SHORT BRAKING MODE or the
REVERSE BRAKING MODE is available.
If you can only get one port, you can control only the MODE2.
At this time, you can control the two kinds of BRAKING MODE
[commutated short or reverse] on condition that the MODE1 is
set to be LOW or OPEN.

BRAKING MODE (ECR < EC) SELECT FUNCTION TABLE

MODE1

MODE2

LOW
or
OPEN

HIGH

LOW or OPEN

COMMUTATED SHORT
BRAKING

REVERSE BRAKING

HIGH

ALL SHORT

BRAKING

OUTPUT OPEN

[only inertia]

Figure 7.

REVERSE TORQUE MODE SELECT FUNCTION

Figure 8 shows an example for the reverse torque mode select.
The CASE1 is an example for controlled REVERSE and
COMMUTATED SHORT BRAKING.
The CASE2 is an example for controlled REVERSE and ALL
SHORT BRAKING.

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

CASE 1

FORWARD

Figure 8.

REVERSE AND COMMUTATED
SHORT BRAKING SELECT

EC PIN INPUT VOLTAGE [ECR VOLTAGE = 2.5V]

5.0V

3.0V

ECR 2.5V

2.0V

0V

HIGH

MODE2

LOW

MODE1

LOW

BRAKING

MODE

+1A

CURRENT

REVERSE

TORQUE

CURRENT

-1A

Commutat­ed short
BRAKING

MOTOR CURRENT [ Rsense = 0.5 ohm ]

-60 0mA

REVERSE
BRAKING

+60 0mA

MOTOR
STOP

CASE 2

REVERSE AND ALL SHORT
BRAKING SELECT

EC PIN INPUT VOLTAGE [ECR VOLTAGE = 2.5V]

5.0V

3.0V

ECR 2.5V

2.0V

0V

HIGH

MODE2

LOW

MODE1

LOW

BRAKING

MODE

+1A

FORWARD

CURRENT

REVERSE

TORQUE

CURRENT

MOTOR CURRENT

-1A

ALL
SHORT
BRAKING

REVERSE
BRAKING

+60 0mA

-60 0mA

( Vbemf-Vd-Vsat ) / Ra

Vd ; diode voltage

Vsat ; npn transistor saturation voltage

Ra ; motor inner resistance

MOTOR
STOP

BASICALLY CHARACTERISTICS

This data is an example for typical sample.

Output saturation voltage and Load current Characteristics.

12.0

11.5

11.0

10.5

Output Voltage (V)

0.76

1.5

0.79

0.86

0.89

0.91

This device can use this
voltage value due to motor
drive.

(Condition Vcc2=Vm=12V, Vcc=5V)

0.98

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

Top side
saturation
voltage

1.05

1.18

1.0

0.62

0.5

0.38

0.07

0

0.13

200 400 600 800 10000

0.25

0.32

Load current (mA)

0.49

Output saturation voltage and Load current Characteristics. (At bootstrap)

By taking advantage of bootstrap function, the output saturation
voltage can be lower.

5.0

4.5

4.0

3.5

0.06

0.12

0.23

0.29

0.35

This device can use this
voltage value due to motor
drive.

(Condition Vcc2=6V,Vm=5V,Vcc=5V)

0.47

0.62

0.76

Bottom side
saturation
voltage

1200

Top side
saturation
voltage

0.83

Output Voltage (V)

1.5

1.0

0.5

0.07

0

0.38

0.13

200 400 600 800 10000

0.25

0.32

Load current (mA)

0.49

0.62

0.76

Bottom side
saturation
voltage

1200

HB terminal voltage and Hall current characteristics.

1.6

1.4

1.2

1.0

0.85

0.8

0.6

HB terminal voltage (V)

0.4

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

(Condition :Vcc=4.4V – 7V)

0.2

0

0

10

20 30

Hall current (mA)

40 50

APPLICATION CIRCUIT

Forward reverse
rotation signal

3

FG signal

37

4

MITSUBISHI <CONTROL / DRIVER IC>

M56785FP

SPINDLE MOTOR DRIVER

µcom control

BRAKING

MODE

SELECT

0 to 1.5

10µF

15

36

7

16

6

12V
Motor
power
supply

5V

Hall bias
resistor

HU

HV

HW

104

TSD

SENSE

CHANGE

MATRIX

120°

BRAKING

MODE

Converter

I / I

39

104

40 41

104

2 38

Start / Stop

104

RDS

FG

23 24 25 26 27 28

20

5

+- +- +-

Bias

Hall

Control
PWM1

Reference
PWM2

+

+

V/I Converter

1817

8 to 14 and 29 to 35

-

Vlim

Motor current sense resistor

0.5

19

5V

Power

Supply

10µF