| 摘要 |
An integrated memory circuit is described which includes a charge pump for producing a pumped voltage and a ring oscillator coupled to the charge pump. The ring oscillator is used to operate the charge pump, such that pump cycles are activated on the edges of the oscillator output. The ring oscillator includes an oscillator enable circuit which is controlled by a regulator to maintain a controlled pump voltage. The oscillator enable circuit immediately shuts the ring oscillator off when the pump voltage reaches a pre-determined upper voltage limit so that additional oscillator cycles are eliminated, thereby, reducing the chance of an overshoot in the pump voltage. The oscillator enable circuit turns the oscillator on when the pump voltage decreases to a predetermined lower level.
|
