Which is better Analog Switch or Relay

Hi,

In my project there is a requirement of switch that will enable constant current of 1mA to flow when switch is ON and voltage level is 28V. Which one is more reliable for this requirement analog switch or Relay?

It would be great if anyone could answer this clarification

Thanks in advance!

An analogue switch is more reliable, but comes with more problems. Any clue to the working frequency?, on/off ratio?
Frank

chuckey said:

An analogue switch is more reliable, but comes with more problems. Any clue to the working frequency?, on/off ratio?
Frank

Click to expand...

Hi Frank,

Thanks for your response.

The Switch will be ON for 3 minutes (maximum) continuously and later it is switched off.

Hi,

Maybe a simple mosfet works....

Klaus

As klaus said use a mosfet .

On/off ratio = Z through switch when on/ Z through switch when off. this effects the available voltage at the output side of the switch. Any other constraints? such as reverse polarity / over voltgate at output?
Frank

Sometime important to know more conditions and parameters, to make a decision what exactly elements will use in scheme.

For example: usually sound signals require use switch without abrupt changes in voltage when switching (use special semiconductor IC audio switches or mosfet with descrete elements); sometime need the high reaction of scheme on change control logic level (not use relay); some application, like measurement application, have need that the switch is a low noice; sometimes important galvanic isolation between the control logic level signal and transmitted signal (use relay or optocouplers); etc.

For signal with a low level without presenting special requirements to the switching element, almost all parameters advantageous to use an ordinary Mosfet transistor or IC switch. Choose elements with a reserve of voltage. Do not forget about the parameters of the gate at the mosfet transistor when selecting transistor.

Hi,

Thanks for all replies....
I have decided to go with Relays since they have Galvanic Isolation when compared to Analog Switches.