WiT WT901B, User Manual

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WT901B | manual v0707 | http://wiki.wit-motion.com/english
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5 IIC Connection
The WT901B module can be connected to the MCU through the IIC interface.
The connection method is shown in the figure below.
Note:
1. In order to connect multiple modules on the IIC bus, the IIC bus of the
module is an open-drain output. When the MCU is connected to the module, the
IIC bus needs to be pulled up to VCC through a 4.7K resistor.
2. VCC is 3.3V, it must be connected to the power supply. Directly using the
power supply on the module may cause a voltage drop, so that the actual
voltage of the module is not 3.3 ~ 5V.
1. The internal pull-up of the MCU is a weak pull-up, the driving capacity is
limited, and an external pull-up on the hardware is required.