MLX90401
Brushless DC Motor Controller
Drivers
I
LOAD
= 50mA
I
LOAD
= 50mA
Top output on resistance
Bottom output on resistance
Rise time
Fall time
Turn-on propagation delay
Turn-off propagation delay
Leakage current
R
ONT
R
ONB
t
r
t
f
t
don
t
doff
I
OFF
32
32
150
150
300
300
-10
Ohm
Ohm
ns
ns
ns
ns
uA
Top drivers
V
OUT
= 60V
Table 3: MLX90401 electrical specifications
7 General description
7.1 Overview
The MLX90401 contains all functions for controlling three-phase brushless DC motors in open loop
applications.
The MLX90401 supports following control functions:
•
speed control
•
forward or reverse rotation
•
braking
•
disable
The chip contains:
•
a rotor position decoder for proper commutation sequencing
•
a voltage reference that supplies power for the sensors
•
a pulse width modulator (PWM) based on a frequency programmable sawtooth oscillator
•
three top and three bottom drivers
Using a bootstrap/charge pump combination, the MLX90401 also generates a boost voltage to drive the top
power FET. In this way the application only uses N-channel power FETS, to reduce overall system cost.
The MLX90401 provides commutation from Hall-effect sensors, and can be configured for motors with 60°
or 120° sensor electrical phasing, by means of a select pin.
Undervoltage lockout is provided.
3901090401
Rev 005
Page 5 of 13
Data sheet
Oct/05
MELEXIS [ Melexis Microelectronic Systems ]
