Not all opamps have explicit offset-null support, but all opamps have offset voltage.
This is exactly my practical circuit:
How do I correct offset voltage of TL084 in this circuit?
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There are a range of methods which can be used to provide offset voltage compensation.
The methods described below can easily be applied to your circuit by
Current injection effectively occurs at a high impedance point and voltage adjustment at a low impedance point but both methods are functionally equivalent. ie Injecting a current causes it to flow in related circuitry and causes a voltage change, and adjusting a voltage causes current flows to alter.
To compensate for offset voltage by injecting a current you can apply an adjustable voltage from a potentiometer via a high value resistor to an appropriate circuit node. To adjust a "ground" voltage that a resistor connects to you can connect it to a potentiometer which is able to vary either side of ground.
The diagram below shows one method. Here Rf would usually connect to ground.
If R1 is a short circuit and R2 an open circuit the whole change in potentiometer voltage is applied to the end of Rf. This causes two problems.
If R1 & R2 form a ~~ 1000:1 divider then R1 will be about 10 Ohms x 1000 = 10k.
The above circuit is taken from the useful Maxim Application note 803 - EPOT Applications: Offset Adjustment in Op-Amp Circuits which contains much other applicable information.
In his answer miceuz referred to NatSemi's AN-31 pages 6 & 7
Not surprisngly, the circuits there apply the identical methods to what I describe above and to those in the Maxim app note, but the diagrams are more explanatory so I've copied them here.
This link has it sorted out. In general, you have to inject correcting voltage into one of inputs.
This PDF has it for inverting and noninverting configuration.