M54685L Datasheet, PDF (1/3 Pages) Mitsubishi Electric Semiconductor – Bi-DIRECTIONAL MOTOR DRIVER WITH GOVERNOR

MITSUBISHI <CONTROL / DRIVER IC>
M54685L
Bi-DIRECTIONAL MOTOR DRIVER WITH GOVERNOR
DESCRIPTION
The M54685L is a semiconductor integrated circuit that is capable
of directly driving a smallsize bi-directional motor rotating in both
forward and reverse directions.
FEATURES
q Wide range of operating voltage (VCC = 4.5 – 14V)
q Possible direct driving with TTL, PMOS and CMOS outputs
q Small outline (10-pin SIP)
q Built-in clamp diode
q Low output saturation voltage (large voltage across motors)
q Large output current drive (IO(max) = 500mA)
q Provided with brake functions
q Built-in thermal shutdown protection circuit
APPLICATION
Micro-cassette for phone-answering machine, tape deck, radio
cassette, and other sound equipment, and VTR and general
consumption appliances
FUNCTION
The M54685L is an IC that can control the forward rotation, reverse
rotation and speed of small DC brush motor.
For the basic operation of this IC, output modes are selected, as
shown in the logic truth table at right, by applying appropriate TTL-
level input to R, L and STB inputs.
The PLAY mode is a mode where speed is controllable and is used
to control the speed of motor by using two resistances, RT and RS,
as shown in the application example. RT and RS are generally
given by the following formulae:
RT = K•Ra (K: current proportional constant, Ra: Motor armature
resistance)
RS = Ka•N/IB (N: rotating speed, Ka: Motor generation constant, IB:
PSC bias current)
FSC and RSC are pins to connect resistance that restricts the
rotating speed in FF and PLAY.
PIN CONFIGURATION (TOP VIEW)
Output 1 O1 1
FF speed control FSC 2
REW speed control RSC 3
Output 2
O2 4
GND 5
Speed control PSC 6
R input
R7
L input
L8
Standby input STB 9
Power supply VCC 10
Outline 10P5
LOGIC TRUTH TABLE
R
L
STB
Mode
L
L
H High speed forward rotation (FF)
L
H
H GOVERNOR forward rotation (PLAY)
H
L
H High speed reverse rotation (REW)
H
H
H Brake
L Standby
BLOCK DIAGRAM ^{Power supply}
VCC
PSC
10
6
Output 2
O2
4
Output 1
O1
1
Governor
circuit
Control circuit
(Thermal protection circuit)
7
R
R input
8
9
L
STB
L input Standby input
2
5
3
FSC
GND
RSC
FF speed control
REW speed control