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EVAL-IMM101T
Smart IPM evaluation board application note
Application Diagrams and Application Use Cases
10.2.2
Sensorless Leg Shunt
The sensorless leg shunts configuration may be used in applications where only very low acoustic noise is
requrired.
M
VSS
RXD0
TXD0
Vbus
1M
1M
13.3k
Vbus sense
Vsp
3.3V
VsV
VsW
C_REF
15V
Rs1
I_Rs1
Rs2
I_Rs2
I_Rs3
Rs3
IW
IU
I_RS3
IV
Vbus sense
Options for Input Set Point:
1- Analog Input Vsp to pin34 P2.0
2- UART input through P0.14 and P0.15
3- Duty (PWM) or frequency input on pin34 P4.6
Other Pins available to the user:
P1.7
If only two shunts are used, P2.2 is available
VrW
Vbus
V
sU
VrU
VrV
V
bW
V
bV
V
ss
1
V
cc
P
1
.7
V
dd
P
2
.10
P2.9
P2.6
Vss2
P2.2
P2.0 / P4.6
P0.15
P0.14
VsU
VbU
VsV
VsW
P
2
.11
/
P
2
.13
2K
10K
3.3V
100
220pF
I_RS2
2K
10K
3.3V
100
I_RS1
2K
10K
3.3V
100
220pF
220pF
Figure 32
IMM101T Sensorless, three leg shunts configuration
EVAL-IMM101T’s current sensing configuration is single shunt by default. To use leg shunt configuration, follow
these steps:
Remove R30 and R31
Mount R80 and R88 equal to 0 Ω
Mount RS2 and RS3
