Constant current source using current feedback op amp

Question

Hi everyone 
 
 I have a weird design challenge. I have to make high bandwidth constant current AC source. Usual constant current sources include voltage feedback op amps that are strait forward in regards to their design, but since the bandwidth has to be so large (1Mhz) i need to use an op amp with current feedback. I have been struggling to figure out the solution to this problem since the output current depends on output load (which is not good) in every circuit i came up with. 
 
 If you have solution to this problem in forms of schematics, or if you can offer any help i would be very grateful 
 
 Best regards

MarkThoren · Accepted Answer

Hi HelterSkelter, 
 You have a challenging problem - First advice: BE CAREFUL! If you are starting from scratch, then the best option would be to buy an off-the-shelf high-voltage amplifier module of some sort. Analog devices does not make these directly. There are various application circuits, but you will need to thoroughly test with your circuit, and implementation can be a challenge, you will need to lay out a proper circuit board for any of them. 
 But once you've got the high-voltage stage figured out, then using a grounded sense resistor will greatly simplify the rest of your circuit - it can operate from a low voltage auxiliary supply. 
 So the best advice we can give in this forum is to find a SAFE, agency approved (UL, CE, etc.), voltage-output power stage, then add a current sense circuit so that the only circuitry you're actually building is low-voltage. 
 
 -Mark)