MLX90401KDF MELEXIS [Melexis Microelectronic Systems], MLX90401KDF Datasheet - Page 10

• Manufacturer Part Number: MLX90401KDF
• Description: Brushless DC Motor Controller
• Manufacturer: MELEXIS [Melexis Microelectronic Systems]

8 Application information
8.1 Evaluation Board
An Evaluation Board for the MLX90401 called EVB90401 is available. The accompanying Application Note
describes the Board, and gives extra information concerning the use of the MLX90401 in real-life
applications.
Consult our website
8.2 Typical application
Shown below is a typical application of the MLX90401 that could be used for battery-operated power tools.
A manual HVAC blower schematic looks similar, but zener DZ1 should be chosen at for instance 18V.
This example system is powered by a 12V battery.
Other components:
3901090401
Rev 005
BT1
12V
10k
R1
5nF
C4
•
•
•
•
•
ON/OFF
SW1
DZ1 is a high power zener diode to clamp the battery line when the system is switched off using
SW1: motor M1 could generate a voltage on the power line after shut down, causing the power line
to rise and potentially exceed the maximum rating of the MLX90401. DZ1 prevents this. Its voltage
specification should be chosen a few volt above the maximum rating of the power supply, but
obviously not higher than the absolute maximum rating of the MLX90401. It should be a high power
device since it has to absorb a lot of energy in a short time.
C1 decouples the power line and should be placed as close as possible to the MLX90401.
R1/C4 are the external RC for the oscillator.
The VREF line is decoupled with C2 and C3. VREF powers the Hall effect sensors and the speed
potentiometer P1. This signal is filtered using R2/C5 to prevent noise of entering the PWM circuit.
A thermal switch is connected to the Disable input to protect the system from overheating: if the
temperature exceeds the thermal switch threshold, it switches on, and disables the motor.
DZ1
14V
5W
100k
Speed
22u/
25V
P1
C2
100n
C1
Disable
Fw/Rev
Brake
60/120
°T
R2
V
100n
REF
www.melexis.com
C3
100n
C5
10
11
12
1
2
3
4
5
6
7
8
9
Supply Voltage
Analog Ground
Fwd/Rev Input
Input / Disable
Power Ground
Oscillator R/C
Hall "A" Input
Hall "B" Input
Hall "C" Input
Speed Adjust
/Brake Input
Select Input
V
60°/120°
REF
for more information.
Out
MLX90401
Figure 4 : Typical application
IC1
Cap Boost "A"
Cap Boost "B"
Cap Boost "C"
Feedback "C"
Feedback "A"
Feedback "B"
Gate Top "C"
Gate Top "A"
Gate Top "B"
Gate Bottom
Gate Bottom
Gate Bottom
Page 10 of 13
"C"
"A"
"B"
24
23
22
21
20
19
18
17
16
15
14
13
R3
R4
R5
R6
R7
R8
Brushless DC Motor Controller
R3 ... R8 = 22R
Q1 ... Q6 = IRF530
D3 ... D5 = 1N4148
D6 … D8 = 1N4007
47n
47n
47n
C6
C7
C8
D1
D2
D3
Q1
Q4
Q2
Q5
MLX90401
Q3
Q6
D4
Data sheet
Oct/05
Brushless DC
D5
Motor
M1
D6