2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

PIN CONFIGURATION (TOP VIEW)

DESCRIPTION

The M54679FP is a semiconductor integrated circuit designed for

stepper motor driver used to Printer, PPC and Facsimile.

FEATURES

Wide supply voltage sphere (10 – 35V).

Bipolar, constant current PWM function.

(Top side transistors PWM function, maximum current is 0.8

Amps).

Few external components.

(This IC can be operated with 1 capacitor and 2 resistances).

4 phases input style (include the protection function of output

through current).

Output current change function (2 bits, 4 type currents).

Thermal protection circuit.

Include flywheel diodes.

APPLICATION

Printer, PPC and Facsimile.

FUNCTION

The M54679FP is a semiconductor integrated circuit which can

drive two phase stepper motor.

It can control the direction of motor current and output motor

current (4 steps) by I0, I1 terminals.

Also, it can drive the two phase bipolar stepper motor by one IC as

it include two current control circuits.

BLOCK DIAGRAM

Outline 42P9R-A

Logic

Vm1

Ph1A

Ph1B

Logic

Ph2A

Ph2B

Logic

Fref

VTM

Rs1

Out1B

Out1A

Out2A

Out2B

VTL

VTH

Frequency

Generator

Spike

current

cancel

Current

comp1

Current

comp2

GND

Source

PWM

Source

PWM

P.GND

Spike

current

cancel

Stby

P.GND

Vm2

Standby

TSD

Regout

(3.5V)

1.25V

10K

18K

Vref

I0(2)

I1(2)

I0(1)

I1(1)

FF1

FF2

4679F

N.C

Out2A

Out2B

Rs2

Vm2

Ph2A

Ph2B

Fref

Regout

I0(2)

I1(2)

N.C

P.GND

Out1A

Out1B

Vm1

Ph1A

Ph1B

Stby

Vref

I0(1)

I1(1)

GND

N.C

GND

N.C: no connection

2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

ABSOLUTE MAXIMUM RATINGS (Ta = 25

C unless otherwise noted.)

Symbol

Conditions

Units

Parameter

Motor supply voltage

-0.3 – 37

PIN FUNCTION

Iout

Vlogic

Vanalog

Topr

Ratings

Output current

Per one phase

0.8

Power supply

-0.3 – V

Analog input voltage

Under board mount condition.

(see next page)

1.5

C/W

Power dissipation

2.7

Thermal derating

Junction temperature

Operating temperature

150

-20 – 75

Rs1, Rs2

Ph1A, Ph1B, Ph2A, Ph2B, I0, I1, Stby

Vref, S1, S2

Tstg

Storage temperature

Logic input voltage

-40 – 125

Terminal

Function

Symbol

Motor Supply Voltage

Output terminals

Current sensor

Power supply

Phase input

Output current change

Standby input

Sense inputs

Vref input

Power supply for motor drive.

Motor drive output terminals.

Output current sensing resistor (Rs) connection terminals.

Control circuit power supply.

Output current direction switch terminals.

Output current change (100%, 70%, 33%, 0%) terminals.

Standby input (L: Standby, H or open: motor function) terminal.

Input voltage terminal of comparators.

Reference voltage due to setting output current.

Vm1, Vm2

Vref

S1, S2

Stby

I0(1), I1(1), I0(2), I1(2)

Ph1A, Ph1B, Ph2A, Ph2B

Rs1, Rs2

Out1A, Out1B, Out2A, Out2B

VRs

Output current sensing

-0.3 – 7.0

-0.3 – V

Regout

Fref

P.GND

Output of voltage stabilizer

A capacitor for oscillator

Power GND

Output of voltage stabilizer (3.5V).

A capacitor due to PWM carrier frequency.

The GND terminal of bottom side flywheel diodes.

2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

ELECTRICAL CHARACTERISTICS (Ta = 25deg, V

= 5.0V, VM = 24V unless otherwise noted.)

Limits

Min.

Typ.

Max.

Symbol

Conditions

Units

Parameter

Supply current

Stby = H, Ph*A = H, Ph*B = L (Bridge ON)

Vlogic L

I(Ph) L

I(S)

V(S)

I(Vref)

CH(H)

Logic input voltage

(Ph, I1, I0, Stby terminals)

Current sensing Comparators

input current

Current sensing Comparators

input voltage sphere

Vref input current

Current sensing Comparators

threshold voltage

Vref input voltage sphere

Stby = H, Ph*A = Ph*B (Bridge OFF)

Vin = 0V

S1 or S2 terminals input current

(S1 or S2 = 0V, Vref = 5V).

S1 or S2 terminal input voltage sphere

Vlogic H

V(Vref)

CH(M)

Oscillation frequency of Fref

C = 390pF, Fref terminal oscillation

I0 = L, I1 = L, Vref = 5V (Vref/10*100%)

I0 = H, I1 = L, Vref = 5V (Vref/10*70%)

2.4

-20

—

-3.0

—

0.6

—

CH(H)

—

I(Ph) H

Phase terminal input current

Vreg

Vin = 5V

—

3.35

3.50

3.65

475

500

525

325

350

375

—

500

650

CONTROL CIRCUIT

FUNCTIONAL CONDITIONS

Limits

Min.

Typ.

Max.

Symbol

Units

Parameter

Power supply

Motor supply voltage

Iout

PLH

Output current

Rising time of logic inputs

5.0

—

5.5

800

2.0

4.5

—

PHL

Falling time of logic inputs

PWM ON time

Ton

Toff

TSDon

PWM OFF time

Thermal shut down

—

160

2.0

—

5.0

—

Stby = L (Standby condition)

2.0

4.0

6.0

I(I0, I1) L

Vin = 0V

-400

-300

—

I(I0, I1) H

I0, I1 terminals input current

Vin = 5V

—

I(Stby) L

Vin = 0V

-400

-300

5.0

I(Stby) H

Standby terminal input current

Vin = 5V

—

CH(L)

Voltage stabilizer output

Input current of Vref (Vref = 5V, I0 = I1 = 0V)

Iout = -0.1mA – +1mA

I0 = L, I1 = H, Vref = 5V (Vref/10*33%)

139

155

171

kHz

2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

(5). Oscillation circuit.

External capacitor is charged and discharged by the constant

current and a triangular waveform appears to Vref terminal.

The waveform voltage level is shown in right figure.

This triangular waveform is a carrier frequency of PWM circuit.

The carrier frequency change if this external capacitor value is

changed.

M54679FP is designed that the oscillation frequency is 30kHz

if the external capacitor value is 390pF.

The oscillation frequency is in inverse proportion to the value of

a external capacitor.

FUNCTION EXPLANATION

(1). Ph inputs make a decision the output function.

(3). Equivalent circuit of Vref terminal.

The equivalent circuit of Vref terminal is shown in right circuit.

As Vref terminal needs typical 500

A input current, consider

this value when Vref voltage is set.

(4). Current sensing comparators.

The current sensing comparators compare the voltage (VR

)

of current sensing resistor and threshold voltage (V

) of this

comparators, then if VR

> V

, the comparators output

change and shut off the output.

Ph*A

Ph*B

Out*A

OFF

Out*B

OFF

*: 1 or 2

The outputs shut off under Ph*A and Ph*B High

condition at the same time.

OUTPUT CIRCUIT (Ta = 25deg, V

= 5.0V, VM = 24V unless otherwise noted.)

Limits

Min.

Typ.

Max.

Symbol

Conditions

Units

Parameter

Vsat

Top and Bottom at Load current 0.6A.

Ileak

—

-100

1.6

—

2.2

+100

Output saturation voltage

Output leakage current

VF(L)

VF(H)

—

1.7

1.1

2.3

1.5

If = 0.6A

VF of flywheel diode (Top)

VF of flywheel diode (Bottom)

tdoff

tdon

—

0.5

2.0

3.5

Time until output become ON since S > Vref

Time until output become OFF since S < Vref

Turn ON delay of output

Turn OFF delay of output

(2). Output current and terminal of output current setting.

Output current ratio

100%

70%

30%

Current sensing comparators

threshold voltage (Vref=5V)

500mV

350mV

—

155mV

Vref

18k

3.5k

0.68k

0.5V

2.5V

2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

(10). Setting output current.

As the output circuit of M54679FP is designed by the bipolar

type NPN transistors, the current that go through the motor

coil is smaller about 15mA (typical) than the current that go

through the current sensing resistor.

This is caused by the base current of the power transistors.

Therefore, be aware this base current when the output

current is set.

(11). Power GND terminal.

Power GND is connected the anodes of flywheel diodes of

bottom side.

When the output H-bridge power stage goes to ON, as the

flyback current go through this GND terminal, minimize the

wire resistor of this GND on the board.

(6). Spike current cancellation.

Output power transistors go to ON, then the spike current

appears on the R

(current sensing) in a short time and this is

caused by the internal delay time.

M54679FP has the cancellation circuit of the spike current as

the current sensing comparators do not cause error functions.

So, the function of current sensing comparators are shut off

during 2

s since the output power transistors go to ON.

(7). Ph signal delay circuit.

M54679FP has a delay time of 3.0

s until output H-bridge

power stage go to ON since Ph signal change Low to high.

This delay time is enough short time for the frequency (plus

rate) of Ph signal and there is no problem in the normal

function.

(8). Rs and S1 or S2 terminal.

If S1 or S2 terminal (non-inverted input of the current sensing

comparators) is connected the nearest position of current

sensing resistor, the error of the current sensing by means of

wire resistance on the board will be decreased.

(9). Voltage stabilizer.

M54679FP has a voltage stabilizer of 3.5V.

The reference voltage (Vref) can connect the output (Regout)

of voltage stabilizer directly.

In this case, the current capability of the output of voltage

stabilizer is 1.0mA (source current), 0.1mA (sink current).

OFF

Iout

Ib = 15mA (Typ.)

Iout = IRS - Ib

2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

(12). Output current timing chart under Ph inputs and I0, I1 output

conditions.

Under output current wave forms show the current that a

motor driver is going to control, so these do not show the

actual current wave forms.

(1)

(2)

(3)

(4)

Ph1A

Ph1B

Ph2A

Ph2B

100%

I0(1),I0(2)

I1(1),I1(2)

<4 steps function>

Output current 1

(Current of Phase 1)

Output current 2

(Current of Phase 2)

(4)

100%

Torque vector

(1)

(2)

(3)

<8 steps function>

Ph1A

Ph1B

Ph2A

Ph2B

I0(1),I0(2)

I1(1),I1(2)

Output current 1

(Current of Phase 1)

Output current 2

(Current of Phase 2)

13 14 15 16

<16 steps function>

Output current 1

(Current of Phase 1)

Output current 2

(Current of Phase 2)

Ph1A

Ph1B

Ph2A

Ph2B

I0(1)

I1(1)

I0(2)

I1(2)

31%

70%

100%

70%

100%

2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

(13). Inputs terminals.

Symbol

Equivalent circuit of the circumstance of input terminals.

Remarks

pin: Stby

pin: I0(1)

pin: I1(1)

pin: I0(2)

pin: I1(2)

pin: Ph1A

pin: Ph1B

pin: Ph2A

pin: Ph2B

pin: S1

pin: S2

pin: Vref

I0(1)

I1(1)

I0(2)

I1(2)

2-PHASE STEPPER MOTOR DRIVER

M54679FP

MITSUBISHI <CONTROL / DRIVER IC>

PRELIMINARY

Notice: This is not a final specification.

Some parametric limits are subject to change.

APPLICATION CIRCUIT

STEPPER MOTOR

Rrs2

Rrs1

input

Ph1A

Ph1B

Regout

Vref

Rs1

Out1B

Out1A

P.GND

GND

Vm1

Ph2A

Ph2B

Vm2

Rs2

Out2A

Out2B

GND

4679F

I1(1)

I0(1)

I1(2)

I0(2)

Fref

N.C

Stby

input

390pF

input

0.5 – 1.0

Ω

0.5 – 1.0

Ω