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What is the most suitable value of pull-up resistor?
A rule of thumb is to use a resistor that is at least 10 times smaller than the value of the input pin impedance. In bipolar logic families which operate at operating at 5 V, the typical pull-up resistor value is 1-5 kΩ. For switch and resistive sensor applications, the typical pull-up resistor value is 1-10 kΩ.
What is the value of the pull up resistors on the I2C wires?
It requires pull-up resistors Since floating is bad, the I2C bus must have pull-up resistors. One on the SDA line and one on the SCL line. They’re typically 4.7K or 10K ohm, but should be in the range of 2K to 10K.
Is there correct resistance value for I2C pull-up resistors?
– Electrical Engineering Stack Exchange Is there a correct resistance value for I2C pull-up resistors? The datasheet of the 24LC256 EEPROM states that: The SDA bus requires a pull-up resistor to VCC (typical 10 kΩ for 100 kHz, 2 kΩ for 400 kHz and 1 MHz).
What is the maximum load capacitance for an i 2 C Bus?
These are theoretical maximum capacitance values; the suggested load capacitance values in the ADUM1250 data sheet are 40 pF for side one and 400 pF for side two. The data sheet values account for design margin, ESD protection, and 400 pF is a standard for an I 2 C bus.
When do pull up resistors pull the line high?
The pullup resistors pull the line high when it is not driven low by the open-drain interface. The value of the pullup resistor is an important design consideration for I2C systems as an incorrect value can lead to signal loss.
What’s the maximum rise time for I2C cabling?
If 1 MHz operating frequency is not necessary, fast mode (400 kHz maximum operating frequency) can be used, which permits a rise time up to 300 ns. With a fixed value of the pull-up resistor ( RP ), a linear relationship between rise time ( tR) and total bus capacitance ( CB) is described by Equation 1.