EVB90401 Datasheet, PDF (4/6 Pages) Melexis Microelectronic Systems – MLX90401 Demo Board

EVB90401
MLX90401 Demo Board
R3
10k
C3
4n7
P1 _R4
100k _1k
Speed
Fw/Rev
Brake
60/120
6 Fwd/Rev Input Feedback "B" 19
7
Speed Adjust
Input / Disable
Cap Boost "C"
18
C6
100n
8 Oscillator R/C Gate Top "C" 17
Q3
9
/Brake Input Feedback "C" 16
10
Analog Ground
Gate Bottom
"A"
15
Q4
11
60°/120°
Select Input
Gate Bottom
"B"
14
Q5
12
Power Ground
Gate Bottom
"C"
13
Q6
Disable
Hall switch
L1
e.g.
US5881
Also, a sense resistor can be used to measure the current through the motor. The current will produce a
voltage drop across the sense resistor. This voltage, amplified and filtered, can be compared with a
reference voltage. If the voltage (proportional to the current) exceeds the reference voltage, the Disable
pin is pulled low and drivers are switched off.
R_OSC
10k
C_OSC
5nF
P1
R4
100k 1k
Speed
Fw/Rev
Brake
60/120
6 Fwd/Rev Input Feedback "B" 19
7
Speed Adjust
Input / Disable
Cap Boost "C"
18
C6
8 Oscillator R/C Gate Top "C" 17
100n
9
/Brake Input Feedback "C" 16
10
Analog Ground
Gate Bottom
"A"
15
Q4
11
60°/120°
Select Input
Gate Bottom
"B"
14
12
Power Ground
Gate Bottom
"C"
13
+
FILTER
A
COMP
-
V_REF
Q3
Q5
Q6
R_SENSE
A Test Pin is available on the Demo Board as a connection point for the Disable signal.
A Test Pin is also available on the Brake signal.
1.4 Bill of Materials for the Demo
• A Demo Board with on-board MLX90401
• A regulated power supply (laboratory power supply, battery etc.)
• A brushless DC motor
• (Oscilloscope)
390119040101
Rev 002
Page 4 of 6
Application Note
15-Jul-05