This present invention relates to a lamp drive apparatus and a drive method for an LCD equipped portable electronics to maintain a user-selected level of brightness in accordance with surrounding temperature of the lamp. In one operation mode a lamp drive apparatus reduces the current, which is applied into the lamp to maintain the already selected level of brightness in accordance with a detected lamp surrounding temperature where the brightness of the lamp has already been set in the LCD, to make the LCD device to illuminate no brighter than the selected level of brightness. Accordingly, the battery power can be used more efficiently or effectively. Thus, the battery life can be extended.