Patent Number: 6,166,955

Title: Apparatus and method for programming of flash EPROM memory

Abstract: An apparatus for programming selected floating gate storage transistors in a data storage device includes a voltage supply circuit, coupled to the control gate and the source of a selected floating gate storage transistor, to supply a gate programming potential across the control gate and the source to move charge in the floating gate. Circuitry, coupled to the selected floating gate storage transistor, maintains drain current of the selected floating gate transistor at a substantially stable value during programming. In one example, the circuitry is a stable current source in parallel with a load coupled to the source of the selected floating gate transistor. The stable current source, in one embodiment, is a current mirror designed to supply a fixed current level. The load may be a resistor chosen to control a slope of a curve of source current versus source voltage such that drain current variation is limited. The load may be a diode chosen to control a slope of a curve of source current versus source voltage such that drain current variation is limited.

Inventors: Lu; Wenpin (I-Lan, TW), Chen; Ming-Shang (Hsinchu, TW), Wang; Mam-Tsung (Hsinchu, TW), Lin; Baw-Chyuan (Yunlin, TW)

Assignee: Macronix International Co., Ltd.

International Classification: G11C 16/12 (20060101); G11C 16/06 (20060101); G11C 16/04 (20060101); G11C 016/04 ()

Expiration Date: 12/26/2017