High voltage switches for nand flash memory

A memory system, comprising:

• a memory device, comprising:
• a first circuit, wherein a first terminal of the first circuit is coupled to a boost voltage terminal and a second terminal of the first circuit is coupled to an output node of the memory device;
• a second circuit, wherein a first terminal of the second circuit is coupled to a first regulated voltage terminal and a second terminal of the second circuit is coupled to the output node;
• a third circuit, wherein a first terminal of the third circuit is coupled to a second regulated voltage terminal and a second terminal of the third circuit is coupled to the output node;
• and
• a string driver, wherein a first terminal of the string driver is coupled to the output node and a second terminal of the string driver is coupled to word lines of the memory device;
• and
• a memory controller coupled to the memory device and configured to control the memory device.

A method of programing a memory device, comprising:

• applying, by a first circuit coupled to a output node, a boost voltage to a first word line or a second word line of the memory device during a first time period;
• applying, by a second circuit coupled to the output node, a first regulated voltage to the first word line during a second time period after the first time period;
• and
• applying, by a third circuit coupled to the output node, a second regulated voltage to the second word line during a third time period after the second time period.