Charge pump circuit, nonvolatile memory, data processing apparatus, and microcomputer application system
US8634255B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 13, 2011 |
| Grant date | Jan 21, 2014 |
| Priority date | — |
| Expiry date | Mar 22, 2032 |
Classification
- Technology area (CPC —)General
Abstract
Improvement technology of a charge pump circuit is provided for avoiding device destruction due to electrification of an intermediate node of plural capacitors coupled in series to form one step-up capacitor, and avoiding reduction of pump efficiency due to leakage current which flows through a leakage path of the intermediate node concerned. A charge pump circuit includes a step-up capacitor configured by a first capacitance and a second capacitance coupled in series, a capacitance driver, and a protection circuit. The protection circuit is set at a conductive state and discharges a stored charge at the series coupling node of the first capacitance and the second capacitance, when the step-up voltage is not generated, and the protection circuit is maintained in a non-conductive state, when the step-up voltage is generated. Accordingly, relaxation of the withstand voltage of the step-up capacitor is achieved, and reduction of the pump efficiency is avoided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.