KIT33771TPLEVB evaluation board,
Rev. 2.0
18
NXP Semiconductors
Configuring the hardware
5.2
Isense connection
A 0.1
Ω
shunt resistor is available on the KIT33771TPLEVB for current measure during demonstrations. It is also possible to use an
external shunt for current measure by disconnecting the embedded one.
5.2.1 Using the embedded 0.1
Ω
shunt (default configuration)
The current should be limited to
±
500 mA to avoid any damage of the EVB.
5.2.1.1
Configuration 1: measuring external load and KIT33771TPLEVB currents
(default configuration)
To measure both currents:
1.
Make sure that R109, R110, R111 (0.1
Ω
shunt) and R115 are populated and R116 is not placed (see
Figure 14
).
2.
Connect the battery stack to the X1-1 to X1-4 connector pins (positive) and the X1-33 connector pins (negative). The current is
considered as negative.
3.
For optional external loads, connect the negative side of the external load should be to the X1-34 connector pins. In this case,
both currents are added.
5.2.1.2
Configuration 2: measuring an external load current only
To measure the external load current only:
1.
Make sure that R109, R110, R111, and R116 are populated and R115 is not placed.
2.
Connect the battery stack should be connected to the X1-1 to X1-4 connector pins (positive) and the X1-33 connector pin
(negative).
3.
Connect the load negative side to the X1-32 connector pin.
Figure 14. Resistor configuration
IS+
R110
0
R111
0.1
R109
0
R115
0
R116
0
DNP
CTR