I would expect to have the DVM wiring catching anything from nearby.Has anyone measured what a high impedance pin looks like
Assuming you are measuring with an infinite resistance voltmeter, the reading would be 3.3V due to the small parasitic pin capacitance.Suppose, for example, say an IC works at 5V. A pin is in a high impedance state at a particular instant. This pin is pulled up to 3.3V since this signal is interfaced with an MCU. Now, let's remove the pull-up to 3.3V on this pin. At this time, anyone can tell me what would be the voltage reading?
if we dive that deep into details, then we need to consider the internal Mosfet introduced Q ... which also modifies the voltage.the reading would be 3.3V
Don't see how that affects the voltage as it's just comes from the fixed capacitance of a static MOSFET (?).if we dive that deep into details, then we need to consider the internal Mosfet introduced Q ... which also modifies the voltage.
True, but the scenario the TS proposed was that the output was already in the High-Z state before the applied voltage was removed.To make the IO high-Z one needs to switch OFF the high side MOSFET.
Why doesn't it start with a "discharged" capacitance = 0V?would be 3.3V due to the small parasitic pin capacitance
I understand that, when an IC pin is in an High Impedance state, the pin is not connected to anything internal. It will be the voltage whatever it is pulled to outside.
But I am just curious as to whether anyone has measured the value of voltage when the pin is in the high impedance state.
Suppose, for example, say an IC works at 5V. A pin is in a high impedance state at a particular instant. This pin is pulled up to 3.3V since this signal is interfaced with an MCU. Now, let's remove the pull-up to 3.3V on this pin. At this time, anyone can tell me what would be the voltage reading? Just curious to understand this scenario.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?