| US 7,576,588 B2 | ||
| Quick turn on apparatus and method for a NMOSFET switch | ||
| Ko-Cheng Wang, Puli Township, Nantou County (Taiwan); and Liang-Pin Tai, Tainan (Taiwan) | ||
| Assigned to Richtek Technology Corp., Hsinchu (Taiwan) | ||
| Filed on Aug. 03, 2006, as Appl. No. 11/498,240. | ||
| Claims priority of application No. 94128959 A (TW), filed on Aug. 24, 2005. | ||
| Prior Publication US 2007/0046358 A1, Mar. 01, 2007 | ||
| Int. Cl. H03K 17/687 (2006.01); H03K 17/04 (2006.01); G11C 5/14 (2006.01) | ||
| U.S. Cl. 327—427 [327/376; 327/530] | 12 Claims |
| 1. A switching circuit comprising:
a first input;
a second input;
an output;
a first NMOSFET switch having a drain coupled to the first input and a source coupled to the output;
a first quick turn on apparatus coupled to a gate of the first NMOSFET switch for maintaining a gate-to-source voltage of
the first NMOSFET switch nonzero but not enough to turn on the first NMOSFET switch when the first NMOSFET switch is off;
a second NMOSFET switch having a drain coupled to the second input and a source coupled to the output; and
a second quick turn on apparatus coupled to a gate of the second NMOSFET switch for maintaining a gate-to-source voltage of
the second NMOSFET switch nonzero but not enough to turn on the second NMOSFET switch when the second NMOSFET switch is off;
a switch and a diode coupled in series between the gate of the first NMOSFET switch and the gate of the second NMOSFET switch;
wherein the gate of the first NMOSFET switch shares charges thereon with the gate of the second NMOSFET switch through the
switch and the diode when the first NMOSFET switch is off.
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