| US 7,368,952 B2 | ||
| Output buffer circuit | ||
| Tsukasa Ojiro, Kawasaki (Japan) | ||
| Assigned to NEC Electronics Corporation, Kanagawa (Japan) | ||
| Filed on Apr. 22, 2005, as Appl. No. 11/111,732. | ||
| Claims priority of application No. 2004-126421 (JP), filed on Apr. 22, 2004; and application No. 2005-091100 (JP), filed on Mar. 28, 2005. | ||
| Prior Publication US 2005/0237085 A1, Oct. 27, 2005 | ||
| Int. Cl. H03K 19/094 (2006.01); H03K 19/0175 (2006.01) | ||
| U.S. Cl. 326—87 [326/86] | 15 Claims |
| 1. An output buffer circuit comprising:
an input terminal for receiving a input signal;
a first output buffer section including complementary semiconductors and outputting a first output signal corresponding to
said input signal;
a second output buffer section including complementary semiconductors and connected in parallel with said first output buffer
section,
wherein said second output buffer section starts to output a second output signal corresponding to said input signal after
said first output signal corresponding to said input signal reaches a reference voltage Von to decide whether an output voltage
of said output buffer circuit is on-state or off-state;
a first predriver section receiving said input signal and applying a first gate voltage to a control terminal of said first
output buffer section; and
a second predriver section receiving said input signal and applying a second gate voltage to a control terminal of said second
output buffer section,
wherein said first gate voltage crosses through a voltage level of a threshold voltage of said first output buffer section
in response to a voltage change of said input signal before said output voltage of said output buffer circuit reaches said
reference voltage Von in response to the voltage change of said input signal, and
said second gate voltage crosses through a voltage level of a threshold voltage of said second output buffer section in response
to the voltage change of said input signal after said output voltage of said output buffer circuit reaches said reference
voltage Von in response to the voltage change of said input signal.
|