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USB-Serial: I2C Lines Pull-Up Resistor – KBA89374

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USB-Serial: I2C Lines Pull-Up Resistor – KBA89374

Version: *A

Translation - Japanese: USB-シリアル:I2Cラインプルアップ抵抗 — KBA89374 - Community Translated (JA)

Question: Do you have to connect the external pull-up resistors for the I2C lines of a USB-Serial Bridge Controller device?


Yes, the SCLK and SDATA lines of the I2C interface of the USB-Serial Bridge Controller device are open drain pins. External pull-up resistors must be connected on these I2C lines. These pull-up resistors should be connected to the VDDD supply. Recommended values for the pull-up resistors are shown in Table 1.

Table 1. Recommended Values for the Pull-up Resistors

     I2C Operating Frequency     Resistor Value
     100 kHz     4.7 KΩ
     400 kHz     2.2 KΩ
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Last update:
‎Oct 25, 2013 06:44 AM
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