M56785FP - Mitsubishi Electric Semiconductor

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

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.

+-+-+-

MATRIX

120°

TSD

Vref

UVWVCC1

EC ECR

Hu+ Hu- Hv+ Hv- Hw+ Hw-

S/S

39 40 41

23 24 25 26 27 28

2 38 19

Hall

Bias

V/I Converter

I / I

Converter

VCC2

RDS

MODE2

GND

MODE1

36 SENSE

MODE3

RDS

MODE4

BRAKING

MODE

CHANGE

BLOCK DIAGRAM

GND

8 to 14 29 to 35

1720

Hw-

N.C

GND

ECR

VCC1

S/S

VCC2

RDS

MODE2

MODE1

N.C

Hu+

Hv-

Hu-

Hv+

Hw+

PIN CONFIGURATION (TOP VIEW)

Outline 42P9R-A

MODE3

MODE4

N.C

GND

N.C: no connection

385

376

349

3310

3211

3112

15 28

16 27

17 26

18 25

21 22

M56785FP

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

Hw- Hw- Sensor amp. input

Pin No. Symbol Function

MODE1 Reverse torque mode select 1

Pin No. Symbol Function

N.C N.C Hu+ Sensor amp. inputHu+Start / Stop

S/S Hu- Hu- Sensor amp. input

RDS Reverse detected signal

Hv- Hv- Sensor amp. input

CIPhase Compensation Hw+ Hw+ Sensor amp. inputMODE2 Reverse torque mode select 2

GND GNDGND GND

Hall amplifier sensitivity selectVM Motor supply voltage MODE4

VCC2 12V supply voltage MODE3 Automatic stop select

EC RSMotor speed control Motor current sense

U Motor drive output UECR The reference voltage for EC

VCC1 V5V supply voltage Motor drive output V

Bias for Hall SensorHB W Motor drive output W

N.C N.C

Hv+ Hv+ Sensor amp. input

FG Frequency generator output

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

ABSOLUTE MAXIMUM RATING (Ta=25 )

Tj Junction temperature ˚C

150

Tstg Storage temperature ˚C-40 +125

Symbol Rating UnitParameter Conditions

16 V15 pinVM Motor supply voltage

VCC1 5V supply voltage V7.019 pin

˚C

Topr Operating temperature -20 +75

Pt Power dissipation W1.2Free Air

V4.5VH(c) Sensor amp.

Differential input range pins

KθThermal derating mW/˚CFree Air 9.6

VCC2 12V supply voltage 16 pin 16 V

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

Io Output current 1.5 ANote 1

29 –358 –14

23 –28

PIN DESCRIPTION

–

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

RECOMMENDED OPERATING CONDITIONS

Symbol Parameter Limits

Min. Typ. Max. Unit

5V Power supply V5.04.5 5.5VCC1

V12.04.5 13.2Motor Power supplyVM mA700Io Output drive current

12.04.5VCC2 12V Power supply 13.2 V

pins mV

p-p

µA

+400 +21

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

Symbol Parameter

Icc1 Sleep Mode Supply

current- 1 and pin total Input Current ( pin low or open) 0 100

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

Vsat Saturation voltage Top and Bottom saturation voltage.

(Load current :500mA)

ECdead-

ECdead+ Dead Zone Control

voltage dead zone EC < ECR

EC > ECR

1.2 1.9 V

-40 -21 0 mV

EC Control voltage Input

range pin [3.3v DSP available] 0.5 4.0 V

Conditions Limits

Min. Typ. Max. Unit

Icc2 Sleep Mode Supply

current- 2 pin Input Current ( pin low or open) 500 µA

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

pins

VH com

VHmin1 Hall sensor amp.

input signal revel MODE4=OPEN or HIGH

1.2 4.5 V

VHmin2 MODE4=GND 35

Hall sensor amp

common mode input

range

Reference voltage

Input range

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

ViH

ViL

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

and pin[MODE4] input voltage

when they are HIGH. 2.0

0.8

mode pin input low

voltage

VOL 3pin[RDS],4pin[FG]

output low voltage Io current = 1mA 0.5 V

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

and pin[MODE4] input voltage

when they are LOW.

Von

Voff

Motor start voltage pin input voltage when it starts up the motor.

*The IC is in the active condition.

*The hall bias is available.

Motor stop voltage pin input voltage when it stops the motor.

*The IC is in the sleep condition.

*The hall bias is off.

2.0

0.8

VHb Hall bias terminal

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

30IHb Hall bias terminal sink

current

mode pin input high

voltage

15 16 2

19 2

23 –28

7 6 37

1.65

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

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

Ambient Temperature Ta ( )

Power Dissipation (Pdp)

0 25 50 75 100 125

1.0

2.0

3.0

4.0

5.0

6.0

(W) 4.0W

using A-type board

3.0W

using B-type board

2.7W

using C-type board

THERMAL DERATING

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.

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

0 – +40mV

0 – -40mV

Figure 1. The characteristics of the control voltage

and motor current ( Torque ).

Current limit

0.6A/V

Current limit

Forward Torque

EC - ECR

Reverse Torque

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

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.

Figure 3.

MODE4

OPEN or HIGH GND

120 degree switching

120 degree

soft switching ** Io current

changes sharply.

The hallamp

minimum input voltage

is 50 mVp-p.

The hallamp

minimum input voltage

is 35 mVp-p.

HALL AMPLIFIER INPUT SENSITIVITY SELECT

HALL AMPLIFIER INPUT AND COMMUTATION

The relationship between the hall amplifier inputs voltage and the

motor current outputs is shown in Figure 2.

Figure 2.

Hu+Hv+Hw+

VUV

Hall elements

Outer loator

FORWARD

EC<ECR

REVERSE

EC>ECR

SINK

SOURSE

Output

current

Hall

inputs U WV

UVWU

SLEEP MODE FUNCTION

START / STOP ( pin)

LOW or OPEN HIGH

Motor Stop

Bias off

Hall-Bias of

Motor on

Bias on

Hall-Bias on

Figure 4.

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

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

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

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).

FORWARD AND REVERSE ROTATION DETECT

FUNCTION

Figure 5.

Hall sensor-amp

FG-amp

RDS FG

MODE3

EC-ECR

VCC1

Hu+ Hu- Hv+ Hv- Hw+ Hw-

Hu+Hv+Hw+

FORWARD

Comparator

Hysteresis

RDS

Hu+Hw+

REVERSE

RDS

Low

High

Low

High Low

High

Low

High

Hv+

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

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.

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 VCC1 by an internal resistor [typ.

10Kohm].

FG FUNCTION

Figure 6.

OPEN or HIGH GND

MODE3

AUTOMATIC

STOP UN-AUTOMATIC

(NON-STOP)

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, in 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.

REVERSE TORQUE MODE SELECT FUNCTION

Figure 7.

BRAKING MODE (ECR < EC) SELECT FUNCTION TABLE

LOW or OPEN

COMMUTATED SHORT

BRAKING

LOW

OPEN

HIGH

OUTPUT OPEN

[only inertia]

HIGH

MODE2

MODE1

REVERSE BRAKING

ALL SHORT

BRAKING

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

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.

REVERSE TORQUE MODE SELECT FUNCTION

Figure 8.

CASE 2

FORWARD

CURRENT

REVERSE

TORQUE

CURRENT

MOTOR CURRENT

+1A

-1A

MOTOR

STOP

MODE2

MODE1

LOW

HIGH

BRAKING

MODE ALL

SHORT

BRAKING REVERSE

BRAKING

+60 0mA

-60 0mA

( Vbemf-Vd-Vsat ) / Ra

EC PIN INPUT VOLTAGE [ECR VOLTAGE = 2.5V]

ECR 2.5V

3.0V

2.0V

5.0V

REVERSE AND ALL SHORT

BRAKING SELECT

CASE 1

EC PIN INPUT VOLTAGE [ECR VOLTAGE = 2.5V]

ECR 2.5V

3.0V

2.0V

5.0V

FORWARD

CURRENT

REVERSE

TORQUE

CURRENT

MOTOR CURRENT [ Rsense = 0.5 ohm ]

+1A

-1A

MOTOR

STOP

MODE2

MODE1

LOW

HIGH

BRAKING

MODE Commutat-

ed short

BRAKING REVERSE

BRAKING

+60 0mA

-60 0mA

REVERSE AND COMMUTATED

SHORT BRAKING SELECT

Vd ; diode voltage

Ra ; motor inner resistance

Vsat ; npn transistor saturation vol tage

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

BASICALLY CHARACTERISTICS

This data is an example for typical sample.

Output saturation voltage and Load current Characteristics.

Bottom side

saturation

voltage

200 400 600 800 10000 Load current (mA)

Output Voltage (V)

This device can use this

voltage value due to motor

drive.

1.0

1.5

10.5

11.0

12.0

11.5

0.5

1200

0.76 0.79 0.86 0.91 0.98 1.05

1.18

0.89

0.07 0.13 0.25 0.38

0.32

0.49 0.62 0.76

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

Top side

saturation

voltage

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

By taking advantage of bootstrap function, the output saturation

voltage can be lower.

Bottom side

saturation

voltage

200 400 600 800 10000 Load current (mA)

Output Voltage (V)

This device can use this

voltage value due to motor

drive.

1.0

1.5

3.5

4.0

5.0

4.5

0.5

1200

0.07 0.13 0.25

0.38

0.32

0.49 0.62 0.76

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

0.06 0.12 0.23

0.29 0.35 0.47 0.62

0.83

Top side

saturation

voltage

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

HB terminal voltage and Hall current characteristics.

010 20 30 40 50

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Hall current (mA)

HB terminal voltage (V)

0.85

(Condition :Vcc=4.4V – 7V)

SPINDLE MOTOR DRIVER

M56785FP

MITSUBISHI <CONTROL / DRIVER IC>

Motor current sense resistor

APPLICATION CIRCUIT

Start / Stop

Hall bias

resistor

Power

Supply

12V

Motor

power

supply

Vlim

40 41

23 24 25 26 27 28

2 38

RDS

36 SENSE

BRAKING

MODE

CHANGE

0 to 1.5

104

8 to 14 and 29 to 35

0.5

10µF

104

µcom control

BRAKING

MODE

SELECT

Forward reverse

rotation signal

+- +- +-

V/I Converter

1817

Control

PWM1

Reference

PWM2

120°

MATRIX

Hall

Bias

TSD

I / I

Converter

FG signal