Hi,
We want to apply a constant current of 1mA to 4 RTD sensors (2 wire connection). This current is intended to be common to all the 4 RTDs (all the 4 first wires are are connected togheter) but the return from each RTD is going to be switched with a TS3A4751.
Can I use the TS3A4751 to switch the return current from each RTD?
Thanks in advance.
Francisco,
Yes, all of our signal switches are bidirectional passive FET switches and can pass a signal from on side of the switch to the other. These switches can be ideally thought of as 0 ohm wires. To determine if the device can support a specific current like you mentioned 1mA above you can look at the abs max current rating.
The TS3A4751 for example can pass up to 100mA of current on each channel.
All switches like the TS3A4751 are not ideally 0 impedance wires but a MOSFET that has parasitic below. In your application it sounds like you will need a device with low on-state leakage current.
You may also want to consider a 4:1 device like the TS3A5017 to mux your 4 signals to one path.
Thank you,
Adam
