eblc1388 said:
Nigel Goodwin said:
Isn't it just a dual opto-coupler?, they are commonly available, as are quad ones.
Not quite. When the input LED lights, a voltage(5-10V) is produced across the output pins that can be use to drive the MOSFET directly.
Err no. I am with Nigel on this, it is an opto and is used alot, esp in traction, and when the voltage that shall be required exceeds the isolation of opto's, custom XFMR are wound.
How would the 5V be generated? it cant.
For high voltage you cannot use MOSFETS (and when I say voltage I am talking of 1KV and above). For a fully controlled switch you have to use IGBT's or BJT's
These take current to turn on, with te BJT being a current-control device and teh IGBT being a voltage-control device - but it has a gate capacitance that needs to be charge => current (MOSFETS suffer from this as well)
Where current and voltage is concerned, power is always there already (or at least the potential for power to be utilised)
THIS has no means of transmitting power, just signal, ie it is an Opto.
LED on one side and photodiodes on the other.
Standard practice for isolation.
Look at CNY17 for an trasisitor output trasisotr or 6n137 (very good) for a TTL output