The switch-signal theory is different from the traditional theory of circuit design. It is not based on the module cells of gates or other ICs, but on the switch devices.

开关-信号理论与传统的电路设计理论不同，它不是以门电路或其它集成块为基本单元，而是以开关元件为构造单元。

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There's no option to switch to the stock ICS keyboard, which is a big disappointment in our eyes.

ENGADGET: LG Optimus L9 review: an affordable mid-level Android handset for T-Mobile