Gate signal line driving circuit and display device
View Patent ↗A gate signal line driving circuit and a display device which can suppress the degradation of an element attributed to the use of the element for a long time, and can realize the prolongation of lifetime of the element are provided. With respect to elements to which a HIGH voltage is applied for a long time, a plurality of elements are connected in parallel, and at least some of the plurality of elements are driven by switching elements.
1. A gate signal line driving circuit which applies a HIGH voltage drive signal to a gate signal line during a signal HIGH period, and applies a LOW voltage drive signal to the gate signal line during a signal LOW period which is a period other than the signal HIGH period, comprising:
a plurality of LOW voltage applying switching elements which are connected in parallel with respect to the gate signal line, and which apply the LOW voltage drive signal to the gate signal line in an ON state respectively; and
a plurality of AC voltage lines, each of the plurality of AC voltage lines being directly connected with a source/drain terminal of one of the plurality of LOW voltage applying switching elements and each supplying a HIGH voltage and a LOW voltage periodically and alternately to the source/drain terminal of the one of the plurality of LOW voltage applying switching elements, wherein:
at least one of the plurality of LOW voltage applying switching elements is brought into an ON state in response to the signal LOW period and at least one of the plurality of AC voltage lines being connected with the at least one of the plurality of LOW voltage applying switching elements is the LOW voltage; and
at least one of the plurality of LOW voltage applying switching elements is brought into an OFF state within the signal LOW period.
2. A gate signal line driving circuit according to claim 1 , wherein the HIGH voltage is applied to the source/drain terminal of said each LOW voltage applying switching element when the LOW voltage applying switching element is in an OFF state.
3. A gate signal line driving circuit according to claim 1 further comprising:
a HIGH voltage applying switching element which is connected to the gate signal line, is in an ON state in response to the signal HIGH period and applies the HIGH voltage drive signal to the gate signal line, and is in an OFF state in response to the signal LOW period; and
a plurality of switching signal supply switching elements which are connected in parallel with respect to the HIGH voltage applying switching element, and apply the LOW voltage to a switch terminal of the HIGH voltage applying switching element in an ON state respectively, wherein:
each of the plurality of AC voltage lines is further respectively connected with a source/drain terminal of one of the plurality of switching signal supply switching elements;
at least one of the plurality of switching signal supply switching elements is brought into an ON state in response to the signal LOW period, and at least one of the plurality of AC voltage lines being connected with the at least one of the plurality of switching signal supply switching elements is in the LOW voltage; and
at least one of the plurality of switching signal supply switching elements is brought into an OFF state within the signal LOW period.
4. A gate signal line driving circuit according to claim 3 , wherein: the HIGH voltage is applied to the source/drain terminal of said each LOW voltage
applying switching element when the LOW voltage applying switching element is in an OFF state; and
the HIGH voltage is applied to the input source/drain terminal of said each switching signal supply switching element when the switching signal supply switching element is in an OFF state.
5. A gate signal line driving circuit according to claim 1 further comprising:
a plurality of control switching elements which are respectively connected to switch terminals of the plurality of LOW voltage applying switching elements, wherein:
a control voltage outputting circuit which applies an output HIGH voltage to switch terminals of said respective LOW voltage applying switching elements by way of the respective control switching elements, wherein the control voltage outputting circuit comprises a holding capacitor which holds the output HIGH voltage;
said respective control switching elements are connected in parallel with respect to an output terminal of the control voltage outputting circuit and are turned on and off alternately; and
an electric charge is supplied to the holding capacitor in response to switching timing of the plurality of control switching elements.
6. A display device provided with the gate signal line driving circuit according to claim 1 .