Other Parts Discussed in Thread: LSF0102, TXU0102-Q1
The pullup resistor requirement in the datasheet is as follows. Is the leakage current of the MCU already taken into account in this equation? Thanks!
This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
The pullup resistor requirement in the datasheet is as follows. Is the leakage current of the MCU already taken into account in this equation? Thanks!
No, but the leakage current (a few µA at most) is insignificant compared to the pull-up current.
(The pull-up current is also limited by the drive strength of the MCU and the other devices; it is likely that you must use much less than 15 mA.)
Thanks for your reply! The situation is that: The current at MCUGPIO is shown in the figure. If the LSF0102 is pulled low close to ground at this time, the MCU current is combined with the pull-up current to form the output. At this point, the output current at the MCU side is calculated to be MA level. May I ask if the LSF0102 can work at this time?
When the LSF input is connected to a push/pull output, you do not need a pull-up resistor. See section 5.2 of the Voltage-Level Translation With the LSF Family application report.
Hey Mingkang,
This should be acceptable as long as it is within the recommended range shown in the datasheet:
Regards,
Jack
Thanks for your reply! If this resistor is required, how do I calculate the value of this resistor?
Direction of level translation: SoC communicates bidirectionally with MCU
Amplitude: 3.3 V to 5 V.
Type of I/O on both sides: Pull push
Rate: 10M
Both the MOSI and /CS signals are unidirectional. For this application, you should use the TXU0102-Q1.
Are there any other signals that you are translating? Are you using SPI or QSPI?
Hi Clemens and Jack,
Thanks for your feedback. Since there's customer design, let's move to email thread.
Thanks
Scarlett