发明名称 |
Dynamic regulation of memory array source line |
摘要 |
To maintain stability of memory array operations, a current source supplies a common source line of a memory. The magnitude of the regulation current from the source is dynamically determined based on the amount of current from the array itself through use of a feedback control signal provided by a current comparator circuit. The current comparison circuit can use either a digital or an analog implementation. |
申请公布号 |
US9177663(B2) |
申请公布日期 |
2015.11.03 |
申请号 |
US201313945117 |
申请日期 |
2013.07.18 |
申请人 |
SanDisk Technologies Inc. |
发明人 |
Huynh Jonathan H.;Wang Sung-En;Pan Feng |
分类号 |
G11C16/30;G11C5/14;G11C16/12 |
主分类号 |
G11C16/30 |
代理机构 |
Davis Wright Tremaine LLP |
代理人 |
Davis Wright Tremaine LLP |
主权项 |
1. A non-volatile memory circuit, comprising:
an array of non-volatile memory cells arranged along a plurality of bit lines connected to a common source line; a pull down device connected between the common source line and ground, wherein the pull-down device includes a first transistor connected between the common source line and ground and having a gate connected to receive the output of the first op-amp; a first op-amp having a first input connected to the common source line, a second input connected to receive a first reference level, and an output connected to control the pull down device; a variable current source connected between a first supply level and the common source line; and a current comparison circuit connected to the pull down device to perform a comparison of the amount of current flowing through the pull down device to a reference value and having an output connected to control the variable current source based upon the comparison, wherein the current comparison circuit includes:
a current mirror connected between a second supply level and ground, having a first leg connected to ground through a second transistor having a gate connected to receive the output of the first op-amp and a second leg connected to ground through a reference current source, wherein the second supply level is of a higher voltage than the first supply level; anda second op-amp having a first input connected to receive a second reference level, having a second input connected to a node of the second leg above the reference current source, and having an output that is a voltage level dependent on the value of the second op-amp's second input relative to the second reference value and is connected to control the variable current source. |
地址 |
Plano TX US |