Dear AE team, We are meeting an application issue of HDC1080, different pull up resistors of SDA/SCL will result of different result. We tested the pull up resistor lower than 2.2Kohm, the communication is error with HDC1080. When changed to 10Kohm, the communication is corre...
The maximum value for an I2C pull-up resistor is limited by the line capacitance of the system to ensure the rise time of the signal can support the desired data rate. The first document here calculates the worst-case bus load of 400pF (max allowed by I2C spec), and thus limits ...
I2C_Pullup_Resistor_CalculationSt**en 上传281.49 KB 文件格式 zip I2C是一种常用的串行通信协议,用于连接微控制器和外设。在I2C总线上,为了确保数据传输的可靠性,需要使用上拉电阻来提供总线上的恢复电流。 I2C上拉电阻的计算需要考虑两个主要因素:总线电容和总线速度。总线电容是指总线上所有设备的电容负载,包括...
page 32 for the maximum and minimum rise time specifications. Optimum value of pull up resistor ...
So, in this case the calculation is(5.0V – 0.4V) / .003A = 1533Ω. That represents the lowest possible pullup resistor value, commonly designated RPyou can use, because anything less would burn out your I2C pins. The value of the resistor would be larger with a smaller IOL, so the...
Perhaps, the internal pull-up resistor value = 2k2Ω is affected to the baud rate in the second situation. In the second situation, Could you try to re-test using the resistor value = 200Ω or 10KΩ pull-up VDD for both SDA and SCL? Best regards, Dan 0 Kudos Reply 11-24-...
上述推导过程可以参考 TI的文档《I2C Bus Pullup Resistor Calculation》https://www.ti.com/lit/an/slva689/slva689.pdf 最终在调试的时候,当我们测量SDA或SCL信号并且逻辑LOW上的电压高于0.4V时,我们就知道可以知道灌电流太高了; 当然,这并不意味着每当灌电流超过3mA时,设备就会立即停止工作。但是,在操作超出...
(i.e. shift the value one bit to the right), yielding an address between 0 and 127. However the addresses from 0 to 7 are not used because are reserved so the first address that can be used is 8. Please note that a pull-up resistor is needed when connecting SDA/SCL pins. Please...
I've finally figured out it is not software but rather the TWI wires have too much noise on them. I've switched pull-up resistor values, types of wire, shortened the wire as much as possible, extra caps on the power side, and reduced the TWI speed to below 10khz. Nothing is really...
4 Example For Fast-mode I2C communication with the following parameters, calculate the pullup resistor value. Cb = 200 pF, VCC = 3.3 V Solution: Taking the values from Table 1: ( ( ) )RP(max) = tr (0.8473 ´ Cb ) = 300 ´10-9 0.8473 ´ 200 ´10-12 = 1.77 kW ( )RP...