Driver circuit for electrochromic display device

A driver circuit for an electro-chromic display device having a persistence effect and a plurality of display elements adapted to display information in response to display information signals, comprising:

• means for generating first and second drive signals in response to a change of each display information signal for thereby driving said each display element, said drive signal generating means including a latch circuit for storing said each display information signal and generating a first output delayed in phase with respect to said each display information signal, first gate means for generating a second output in response to said each display information signal and said first output, said second output representing said change of said each display information signal, second gate means for generating a third output having a narrow pulse width in response to said second output and a clock pulse having a pulse width equal to said narrow pulse width, third gate means for generating said first drive signal in response to said each display information signal and said third output, and fourth gate means for generating said second drive signal in response to said third output and an inverted value of said each display information signal;
• and
• means for generating control signals just prior to said drive signals in response to said change of said each display information signal for thereby short-circuiting said each display element just prior to driving said each display element, said control signal generating means including gate means for generating said control signals just prior to said first and second drive signals in response to said second output and said clock pulse whereby said each display element is driven just after an electrical charge stored in said each display element has been discharged;
• said first and second drive signals having a narrow pulse width, whereby said each display element is driven only for predetermined short time intervals and maintained in its open state during time intervals other than said predetermined short time intervals to display said information due to its persistence effect.

A driver circuit for an electro-chromic display device having a persistence effect and a plurality of display elements adapted to display information in response to display information signals, comprising:

• means for generating first and second drive signals in response to a change of each display information signal for thereby driving said each display element;
• means for generating control signals just prior to said drive signals in response to said change of each said display information signal for thereby short-circuiting said each display element just prior to driving said each display element said control signal generating means including gate means for generating said control signals prior to said first and second drive signals in response to said change of display information signal and a clock pulse having a narrow pulse width;
• and
• means for applying regenerative timing signals to said drive signal generating means whereby said drive signal generating means generates auxiliary drive signals to regeneratively drive said each display element to maintain said each display element in its first and second display states;
• said first and second drive signals having a pulse width equal to said narrow pulse width, whereby said each display element is driven only for predetermined short time intervals and maintained in its open state during time intervals other than said predetermined short time intervals to display said information due to its persistence effect.

A driver circuit for an electro-chromic display device having a persistence effect and a plurality of display elements adapted to display information in response to display information signals, comprising:

• a source of first and second clock pulses, said first clock pulse having a frequency higher than that of said second clock pulse;
• means for storing each of said display information signals and generating a first output delayed in phase from said each display information signal in response to said second clock pulse;
• means for generating a second output in response to said each display information signal and said first output;
• means for generating first and second drive signals in response to said first clock pulse and said second output;
• electronic switching means responsive to said first and second drive signals for driving each of said display elements;
• and
• means for generating a control signal just prior to each of said first and second drive signals in response to said second output and said first clock pulse for short-circuiting said each display element to discharge an electrical charge stored in said each display element just prior to driving said each display element;
• said first and second drive signals having a pulse width equal to said first clock pulse, whereby said each display element is driven only for predetermined short time intervals and maintained in an open state during time intervals other than said predetermined short time intervals to display said information due to its persistence effect.