Part Number: TS3DS10224
With this device, what happens when Vcc=0V but there is a 5V signal on the input? Are they effectively high impedance? I noticed a spec in the datasheet for Fail-Safe protection and I was wondering.
The Fail-Safe (IOFF) protection you are talking about is shown:
This is stating that if Vcc = 0V your VIO can range from 0V to 3.6V and will have a max leakage current of ±5uA.
However, I would pay close attention to the 5V signal on the input you mentioned. The recommended operation conditions specify the input/output voltage to not go above Vcc which has a recommended Max of 3.6V.
Additionally, we cannot guarantee performance in the electrical specifications table outside of the recommended operation conditions. The 5V signal you mentioned is even above the Abs. Max ratings of 4V for Vcc and 4.3V for IO voltages and can cause permanent damage to the device and or affect device reliability.
I have also linked to an old E2E post to calculate the impedance.
In reply to Dakotah:
In reply to Kareem Moulana:
As you mentioned, other devices specify the clamp current rating for the device. Unfortunately, any values specified in other datasheets should not be used as design parameters for your current device as they may differ.
The schematic of the part is proprietary information and can not be provided. We will look into updating the datasheet values by adding this to our backlog and address it as the business case warrants.
Additionally, the abs. max table shown is for the TS3USB221.
Make sure to pay close attention to the values provided. The Ik current max is at -50mA. And the Vin voltage is specd at Vin < 0. What this is saying is that the clamping diode from Vin to GND will kick in and clamp negative voltages up to that -50mA max. This does not specify a clamping diode to Vcc. This may help while looking into future parts.
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with respect to these materials. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.