Datasheet M51970L Datasheet (Mitsubishi)

MITSUBISHI <CONTROL / DRIVER IC>

)

(+)

y

M51970L

MOTOR SPEED CONTROL

DESCRIPTION

The M51970L is a semiconductor integrated circuit designed to
control the motor rotating speed.
Connection of the rotating speed detector (F-G detector) to the
input keeps the motor rotating speed constant with high precision.
Connection of an appropriate power transistor to the output
controls a wide range of DC motors.

FEATURES

●Wide range of supply voltage •••••••••••••2.5 – 18V (-20 – +75˚C)

●Variation coefficient of supply voltage

• • • • • • • • • • • ±0.1% standard (4 – 15V)

●Load variation coefficient ••••••••••••••••••••••••••±0.1% standard

●Temperature coefficient of rotating speed

• • • • • • • • • • • • • • ±10 ppm/˚C (standard)

(-20 – +75˚C)

● The built-in over-shoot prevention circuit keeps the over-shoot
low.

● DC drive system with minimum RFI

APPLICATION

Motor rotating control in the player, tape recorder, etc.

RECOMMENDED OPERATING CONDITIONS

Supply voltage range ••••••••••••••••••••••••••••••••••••••••2.5–18V
Rated supply voltage ••••••••••••••••••••••••••••••••••••••••••••••• 9V

PIN CONFIGURATION(TOP VIEW

Time constant

Stabilized voltage

(+)GND

(–)Power supply

Current limit resistance

Integration capacitance

Input

Output

1
2
3

M51970L

4
5
6
7
8

Outline 8P5

BLOCK DIAGRAM

2

Input

4

GND

(–)Power

suppl

5

Stabilized

power
supply

Stabilized voltage

Amplifier

3

Time constant

1

Mono
multi-

vibrator

Integrated capacitance

8

Integrator

Overshoot

prevention circuit

Current

limit circuit

Current

amplifier

Current limit

7

resistance

6

Output

ABSOLUTE MAXIMUM RATINGS(Ta=25°C unless otherwise noted

)

)

)

(2)

(1)

MITSUBISHI <CONTROL / DRIVER IC>

M51970L

MOTOR SPEED CONTROL

Symbol

Vcc
I

6

I

3

Supply voltage
Sink current into pin
Source current from pin

Parameter Conditions

6

3

With printed circuit board mounted (copper foil of 4.5 x 5.5

PdF

Power dissipation

cm in area, thickness of 35µ, printed circuit board of 2.0
mm in thickness)

K

θF

Topr
Tstg

Thermal derating
Operating temperature
Storage temperature

ELECTRICAL CHARACTERISTICS(Ta=25°C, Vcc=9V unless otherwise noted

Symbol Test conditions UnitParameter

CC Supply voltage range

V

CC

I
VS
VTH

RIN

ISC
T

τ

Reg­Reg­TCN

Circuit current
Stabilized output voltage
Input threshold voltage

2

Input impedance
Output limit current

6

One-shot pulse width
Motor speed stability for Vcc

VCC VCC = 4 – 15V

Motor speed stability for load

L

Motor speed stability for temperature

Ta = -20 – +75˚C
Except for output drive current

RSC = 27Ω
Rτ = 75kΩ, Cτ= 22,000pF

Ta = -20 – +75˚C

Ratings

18
40

-3

550

5.5

-20 – +75

-40

– +125

Limits

Min. Typ. Max.

18

2.5
3

1.8

-50

4.2

20

375

–

4.5

2.0
0

7.9
27

395

8

2.2
50

12
35

415

±0.1
±0.1

±10

Unit

V
mA
mA

mW

mW / °C

°C
°C

V

mA

V

mV

kΩ

mA

µs

%
%

ppm/˚C

TYPICAL CHARACTERISTICS(Ta=25°C unless otherwise noted

Thermal derating (Maximum rating)

1000

(1)IC only

900

(2)With printed circuit board mounted

(copper foil of 4.5 x 5.5 cm in area,

800

thickness of 35µ, printed circuit board

700

of 2.0 mm in thickness)

600

500
400

300

Power dissipation Pd (mW)

200

100

0

0 25 50 75 100 125

Ambient temperature Ta (°C)

The data on the next page was measured with the
following constants in the “Application Circuit Example”
given below.
R1=100kΩ, R2=30kΩ, CF1=1µF, CF2=4.7µF, RF=4.7kΩ,
Rτ=75kΩ, Cτ=22,000pF, RSC=56Ω, number of tacho­generator poles; 10 poles. Motor speed - ambient
temperature characteristics is measured with Rτ and Cτ
put out of the temperature test chamber.

MITSUBISHI <CONTROL / DRIVER IC>

)

M51970L

MOTOR SPEED CONTROL

Rotating speed–Supply voltage characteristics Rotating speed–Motor torque characteristics

3060

No load

3055

Rotating speed N (rpm)

3035

01020

Supply voltage Vcc (V)

3060

3055

Vcc = 6V

Rotating speed N (rpm)

3050

0 50 100

Torque T (g-cm

Vcc = 9V

Rotating speed–Ambient temperature characteristics Circuit current–Supply voltage characteristics

3060

3055

Vcc = 9V

No load

5

Except for sink
current to pin

4

3

2

6

Rotating speed N (rpm)

3050

020

-20 40 60 80
Ambient temperature Ta (°C)

APPLICATION CIRCUIT EXAMPLE

Motor rotating speed control circuit

+

10µ

Rτ

Cτ

R2

G

Tacho-generator

R

1

2

3

+

CF1

4 8

M51970L

1

5

Circuit current Icc (mA)

1

0

01020

Supply voltage Vcc (V)

F

R

+

CF2

6

M

7

Motor

VCC

R

SC

(Note 1) How to determine Rτ and Cτ

This constant determines the motor rotating speed. If the motor
rotating speed and the number of poles in the tacho-generator are
assumed to be N and P,
expression is generally established. Putting Rτ in the range of
10kΩ to 500kΩ, select the constant according to the required
rotating speed.

NP

respectively, the following relational

1

=

1.17Rτ Cτ

MITSUBISHI <CONTROL / DRIVER IC>

M51970L

MOTOR SPEED CONTROL

Tacho-generator output frequency–

Connection resistance characteristics of pin

10000

5000

ISC

0.022

µF

=

0.01

µF

70

C

τ

=4700pF

µF

0.7(V)
RSC

200 300 500

3000
2000

1000

700
500

300
200

Tacho-generator output frequency NP (Hz)

100

10 100

(Note 2) How to determine RSC

According to the relation with maximum current ISC flowing to pin ,
the following relational expression is generally established. Set I
in such a way that the value cannot exceed the maximum rated
value of the power dissipation of the M51970L when the supply
voltage and temperature arrive at their maximum values.

0.047

0.1
µF

20 30 50

Connection resistance Rτ (kΩ) at pin

1

1000

1

6

SC

Maximum drive current at pin –

6

current limit resistance characteristics

50

6

40

30

20

10

Maximum drive current at pin

0

0 100 200

20 40 60 80 120 140 160 180

Current limit resistance RSC (Ω)

(Note 3) How to determine CF1, CF2 RF

Select CF1 and CF2 RF according to the inertia of motor and
required rising characteristics.