I have a very PCI analog output card which could output the voltage ranged from 0 to 5V. I need a circuit to output current ranged from 10mA to 90mA. The load is about 45 Omega in resistance. So is it safe to connect directly the analog output to the load and change the voltage until we get the desire current? Will it burn the card if it is not correctly connected? I am sorry that I don't have much experience in circuit building. But I read other article about using op-amp to control the output current by input voltage.

^{simulate this circuit – Schematic created using CircuitLab}

I wonder if above schematic is a correct setup to apply a current to a load? What's the advantage to the op amp for this purpose? Thanks.

I have a very PCI analog output card which could output a voltage ranged from 0 to 5V. I need a circuit to output a current ranged from 10mA to 90mA. The load is about 45 Ohm. 

So is it safe to connect directly the analog output to the load and change the voltage until we get the desire current? Will it burn the card if it is not correctly connected? 

I am sorry that I don't have much experience in circuit building. But I read other article about using op-amp to control the output current by input voltage.

^{simulate this circuit – Schematic created using CircuitLab}

I wonder if the above schematic is a correct setup to apply a current to a load? What's the advantage to the op amp for this purpose?