Abstract: Methods, systems, and devices for grouping power supplies for a power saving mode are described to configure a memory device with groups of internal power supplies whose voltage levels may be successively modified according to a group order signaled by an on-die timer. For example, when the memory device enters a deep sleep mode, respective voltage levels of a first group of internal power supplies may be modified to respective external power supply voltage levels at a first time, respective voltage levels of a second group of internal power supplies may be modified to respective external power supply voltage levels at a second time, and so on. When the memory device exits the deep sleep mode, the groups of internal voltage supplies may be modified from the respective external power supply voltage levels to respective operational voltage levels in a group order that is opposite to the entry group order.

Abstract: Apparatus and methods of operating such apparatus include applying a first voltage level to a source connected to a first end of a string of series-connected memory cells, applying a second voltage level to a data line connected to a second end of the string of series-connected memory cells, and applying a third voltage level to a first access line coupled to a first memory cell of the string of series-connected memory cells concurrently with applying the first and second voltage levels, wherein the magnitude of the third voltage level is greater than the magnitude of both the first voltage level and the second voltage level, and wherein a polarity and the magnitude of the third voltage level are expected to decrease a threshold voltage of the first memory cell when concurrently applying the first, second and third voltage levels.

Abstract: A band gap voltage reference circuit operates between a positive supply voltage and ground. The inputs to a difference amplifier of the band gap reference circuit are biased above the voltage drop of the base-emitter junctions of the band gap reference. The bias voltage is then subtracted from the difference amplifier output by a second difference amplifier. In addition, a bootstrap circuit assures a nonzero output from the first difference amplifier. Other embodiments wherein the band gap reference circuit is more generally a summing circuit are disclosed.