m51971 Mitsumi Electronics, Corp., m51971 Datasheet - Page 9

• Manufacturer Part Number: m51971
• Description: Motor Speed Control
• Manufacturer: Mitsumi Electronics, Corp.

Application Circuit Examples
I. When the output impedance of the tacho-
C
R
R
R , C : Time constant for motor speed setup
C
Notes:
1. The signal amplitude of the tacho-generator for set motor
2. FG amplifier gain
3. The C
II. When the output impedance of the tacho-
G
S
S
NF
F1
rotating speed must be set to 1 mV
follows:
(Values omitted)
generator is low;
, R
generator is high and the signal amplitude is
small;
: Coupling capacitor for AC amplification
, C
, C
C
G
f
S
C
: FG amplifier gain set resistance
F2
NF
S
, R
S
: Filter for noise removal
R
, R
C
R
2
R
S
1
F
S
NF •
G
G
S
S
: Phase compensation capacitance and resistance to
: Angle frequency of tacho-generator signal
, R
4.7 F
2
stabilize integration and speed control systems
C
2
R
C
NF
NF
R
f
1
S
f
3
R
and C
3
R
S
R
NF
1
NF
G
7
4
M51971FP
1+
4
M51971L
C
NF
1
M51971FP
G
M51971L
7
C
NF
1+
NF
values are desirable to be selected as
2 G
C
5
2 G
5
S 2
C
R
M : Motor
G : Tacho-generator
(R
S 2
R
C
C
P-P
C
S
R
F1
C
+Rf)
F1
S 2
6
6
or more.
8
8
2
10
10
R
C
R
C
F
F2
F
F2
9
9
M
M
V
V
CC
CC
III. When the signal amplitude of the tacho-
In the above three examples, the portion over V
output waveform at pin
diode.
IV. When the input waveform is pulse shape
Note: The threshold voltage at pin
V. When turning the motor ON/OFF with control
Input pulse signal
generator is large;
signals;
R
1
When Q
When Q
2
G
7
MITSUBISHI <CONTROL / DRIVER IC>
3
3
2
4
C
1
1
M51971FP
1
F1
M51971L
is set to ON
is set to OFF
R
NF
8
5
M51971FP
M51971L
1
4
M51971FP
3
M51971L
R
C
7
is clipped in the built-in waveform clip
MOTOR SPEED CONTROL
R
C
C
NF
F
5
F2
7
6
: Stops the motor.
: Controls the motor rotating speed.
5
Q
R
1
C
4
R
C
F1
10
C
M51971L/FP
to GND is approx. 1.9V.
6
C
F1
Control signal
8
6
8
10
R
9
1
10
R
C
F
F2
R
C
9
F
F2
9
M
f
(0.7V) of the
M
V
M
CC
V
CC
V
CC