M56784FP Datasheet, PDF (4/11 Pages) Mitsubishi Electric Semiconductor – SPINDLE MOTOR DRIVER

MITSUBISHI <CONTROL / DRIVER IC>
M56784FP
SPINDLE MOTOR DRIVER
ELECTRICAL CHARACTERISTICS
(VCC1=5V, VCC2=12V, VM=12V, Ta=25°C Unless otherwise noted.)
Current limit
0 – +40mV
Reverse Torque
0.6A/V
0.6A/V
Forward Torque
0
EC - ECR
0 – -40mV
Current limit
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.
Figure 1. The characteristics of the control voltage and motor current (Torque).
THERMAL DERATING
6.0
(W)
4.1W using H-type board
5.0
3.1W using I-type board
This IC’s package is POWER-SSOP, so
4.0
improving the board on which the IC is
mounted enables a large power dissipation
2.9W using J-type board
without a heat sink.
3.0
For example, using an 1 layer glass epoxy
resin board, the IC’s power dissipation is 2.9W
at least. And it comes to 4.1W by using an
2.0
improved 2 layer board.
The information of the H, I, J type board is
shown in the board information.
1.0
0
25
50
75
100
125
150
Ambient Temperature Ta ( )