On-Chip Control Circuit for High Positive and Negative Voltages
Original Publication Date: 1984-Jan-01
Included in the Prior Art Database: 2005-Feb-02
This article describes a circuit which enables high voltages (positive and/or negative) to be switched on an integrated circuit chip without damage to the devices on the chip. Such circuits are particularly suited for use in an alterable read-only chip where different voltage levels are required for establishing different operating modes. The figure shows the circuit which coacts with select decode circuitry (not shown) to establish a plurality of operating states. In order to write and/or read a floating gate device (not shown), a large positive voltage and a large negative voltage are needed at node 1. Particularly, a large positive voltage is needed to erase the device, while a large negative voltage is needed to write the device.