maximum linear transconductance (gm(max))

The maximum slope of the ID-VGS curve in the linear region.

NOTE 1 The gate voltage is varied in increments no greater than 20 mV from below the turn-on voltage to a value great enough to ensure that the maximum slope point has been reached.

NOTE 2 The slope is calculated using a three-point linear least-squares best-fit algorithm as defined in ASTM F617‑86.

References: 

JESD28-A, 12/01
JESD60A, 9/04
JESD90, 11/04