Switched Polarity Charge Pump for NOR-type Flash Memories

The era of nano technology and SOC´s is driving the need for better and more compact design of embedded flash memories. This paper discusses circuit technique for a switched polarity 1.8 V charge pump based on Dickson´s charge pump. The circuit can generate typical voltage levels for flash memories during both program and erase operations. The charge pump utilizes the same circuit elements to generate both positive and negative voltages using two non-overlapping clocks resulting in a very simple and compact design. Simulation studies comparing our design with a recent design of a charge pump show the advantages of our design in terms of rise time, charging characteristics, and area.