Display apparatus, digital-to-analog conversion circuit and digital-to-analog conversion method
View Patent ↗A signal line drive circuit according to the present invention has: a latch circuit which latches digital pixel data; a D/A converter which converts a latch output from the latch circuit into an analog video signal; an AMP which amplifies the analog video signal converted by the D/A converter; and a signal selection circuit which selects a signal line to which the analog video signal amplified by the AMP is supplied. The AMP has: an odd number of inverters which are cascade-connected; capacitor elements which are respectively connected between stages of the inverters and between an input terminal of the inverter on a first stage and an output terminal of the inverter on a last stage; a first power supply line which supplies a power supply voltage to the inverter on the first stage; and a second power supply line which supplies a power supply voltage to inverters other than the inverter on the first stage. The accuracy of the AMP can be improved by separating the power supply line for only the inverter on the first stage.
1. A display apparatus comprising:
signal lines and scanning lines which are vertically and horizontally provided in rows on an insulation substrate;
display elements which are formed in the vicinity of the respective intersections of said signal lines and said scanning lines;
a scanning line drive circuit which drives said scanning lines;
a signal line drive circuit which is formed on said insulation substrate and drives said signal lines; and
a power supply voltage generation circuit which generates a second power supply voltage having a voltage level which is a substantially integral multiple of a first power supply voltage supplied from the outside based on said first power supply voltage,
said signal line drive circuit having:
an amplifier which amplifies an analog video signal; and
a signal line selection circuit which selects a signal line to which said analog video signal amplified by said amplifier is supplied, and performs signal line writing, said amplifier being driven with said second power supply voltage, and
said amplifier comprising,
capacitor elements respectively connected between stages of three inverters which are cascade-connected,
switching circuits each of which is provided in accordance with each of said three inverters and capable of switching whether input and output terminals of a corresponding inverter is short-circuited,
a first impedance element connected between said second power supply line and a first power supply terminal of each of said odd number of inverters, and
a second impedance element which is connected between a ground potential line and a second power supply terminal of each of said odd number of inverters, and has an impedance smaller than that of said first impedance element.
2. The display apparatus according to claim 1 , wherein a digital circuit component in said signal line drive circuit is driven with said second power supply voltage.