Control of AxB matrix thermal printhead

摘要

A semiconductor chip controls an A x B matrix of heaters in a thermal printhead in accordance with a digital code stored in a buffer register. A logic array gated to the register is programmed selectively to enable A control lines leading to columns of heaters. A counter sequentially enables B control lines leading to rows of heaters. Control logic is responsive to a function code to initiate a printing operation in which a counter operates in response to a condition in the control logic to immobilize the control logic and to initiate B successive burn/cool cycles each followed by incrementing the row counter. Responsive to a final condition in the row counter, the control logic is again rendered operable.