| US 7,589,549 B2 | ||
| Driver circuit and test apparatus | ||
| Kensuke Kamo, Tokyo (Japan); Takashi Sekino, Tokyo (Japan); and Toshiaki Awaji, Tokyo (Japan) | ||
| Assigned to Advantest Corporation, Tokyo (Japan) | ||
| Filed on Nov. 16, 2007, as Appl. No. 11/941,083. | ||
| Prior Publication US 2009/0128181 A1, May 21, 2009 | ||
| Int. Cl. G01R 31/26 (2006.01) | ||
| U.S. Cl. 324—765 [327/424] | 9 Claims |
| 1. A driver circuit that has a first operational mode and a second operational mode and outputs an output signal according
to an input signal, comprising:
a first driver section that, in the first operational mode, generates and outputs the output signal according to the input
signal and, in the second operational mode, outputs a power supply power having a predetermined voltage; and
a second driver section that, in the first operational mode, receives the output signal output by the first driver section
and outputs the received signal to the outside and, in the second operational mode, generates the output signal according
to the input signal and outputs the thus generated signal to the outside, wherein the second driver section includes,
a first transistor that, in the second operational mode, generates the output signal by operating according to the input signal
and receives the power supply power from the first driver section; and
a second transistor that, in the second operational mode, operates differentially with respect to the first transistor and
receives the power supply power from the first driver section commonly with the first transistor.
|