Write circuit for an erasable programmable read only memory device of a microcomputer
US4747079A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 17, 1986 |
| Grant date | May 24, 1988 |
| Priority date | — |
| Expiry date | Sep 17, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/32
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A write circuit for an EPROM device of a microcomputer comprises a first circuit responsive to an external clock signal WCLK and machine clock signals for supplying a clock signal CLK to a program counter of the microcomputer so as to successively increment an address produced in the program counter, where the external clock signal WCLK has a frequency lower than those of the machine clock signals and the clock signal CLK has different frequencies during normal and write-in operation modes so that the address produced in the program counter is successively incremented in synchronism with the machine clock signals during the normal operation mode and is successively incremented in synchronism with the external clock signal WCLK during the write operation mode, and a second circuit responsive to the machine clock signals and a bit data of a LSB of the address from the program counter for generating a bit line clock signal BCLK for inhibiting a write-in data from being written into the EPROM device during a time period in which the address changes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.