Patent ID: 6882485

Claim:
A system for calibrating a write current of a current mode write driver comprising: the current mode write driver having a first PFET coupled to a first NFET at a first node which is connected to a first side of a write head of the write driver, and a second PFET coupled to a second NFET at a second node which is connected to a second side of the write head, and defines an INODE where a source of the first NFET is coupled to a source of the second NFET and are coupled to a programmed current source, and the current mode write driver is put in a state where all four FET devices are in an off condition; a precision resistor R, connected from the INODE of the write driver to a positive potential, such that a current I 1 is caused to flow through the precision resistor, wherein a voltage V across the precision resistor is measured and then the actual value of the current I 1 is precisely calculated from I 1 =V/R.