Current drive circuit and display device using the same, pixel circuit, and drive method

A display device comprising

• a scanning line drive circuit for successively selecting scanning lines,
• a data line drive circuit including a current source for generating a signal current having a current level in accordance with brightness information and successively supplying the same to data lines, and
• a plurality of pixels arranged at intersecting portions of the scanning lines and the data lines and including current driven type light emitting elements emitting light by receiving the supply of the drive current, wherein
• each pixel comprises
• a receiving part for fetching the signal current from a data line when the scanning line is selected,
• a converting part for converting a current level of the fetched signal current to a voltage level and holding the same, and
• a drive part for passing a drive current having a current level in accordance with the held voltage level through the light emitting element,
• wherein
• the converting part includes a conversion use insulating gate type field effect transistor provided with a gate, a source, a drain, and a channel and a capacitor connected to the gate, the drive part shares the conversion use insulating gate type field effect transistor together with the converting part in a time division manner, and
• the drive part separates the conversion use insulating gate type field effect transistor from the receiving part and uses the same for driving after the conversion of the signal current is completed and passes the drive current to the light emitting element through the channel in a state where the held voltage level is applied to the gate of the conversion use insulating gate type field effect transistor.

A pixel circuit for driving a current-driven type light emitting element arranged at an intersecting portion of a data line supplying a signal current of a current level in accordance with brightness information and a scanning line supplying a selection pulse and emitting light by the drive current, comprising

• a receiving part fox fetching the signal current from said data line in response to a selection pulse from said scanning line,
• a converting part for converting a current level of the fetched signal current to a voltage level and holding the same, and
• a drive part for passing a drive current having a current level in accordance with the held voltage level through the light emitting element, wherein
• the converting part includes a conversion use insulating gate type field effect transistor provided with a gate, a source, a drain, and a channel and a capacitor connected to the gate,
• the drive part shares the conversion use insulating gate type field effect transistor together with the converting part in a time division manner, and
• the drive part separates the conversion use insulating gate type field effect transistor from the receiving part and uses the same for driving after the conversion of the signal current is completed and passes the drive current to the light emitting element through the channel in a state where the held voltage level is applied to the gate of the conversion use insulating gate type field effect transistor.

A method of driving a light emitting element for driving a current-driven type light emitting element arranged at an intersecting portion of a data line supplying a signal current of a current level in accordance with brightness information and a scanning line supplying a selection pulse and emitting light by the drive current, comprising

• a receiving routine for fetching the signal current from said data line in response to a selection pulse from said scanning line,
• a converting routine for converting a current level of the fetched signal current to a voltage level and holding the same, and
• a drive routine for passing a drive current having a current level in accordance with the held voltage level through the light emitting element,
• the converting routine includes a routine using a conversion use insulating gate type field effect transistor provided with a gate, a source, a drain, and a channel and a capacitor connected to the gate,
• in the routine, the conversion use insulating gate type field effect transistor creates the voltage level converted by passing the fetched signal current though the channel in the receiving routine at the gate, and the capacitor holds voltage level created at the gate, and
• the drive routine part shares the conversion use insulating gate type field effect transistor together with the converting part in a time division manner, and the drive routine separates the conversion use insulating gate type field effect transistor from the receiving part and uses the same for driving after the conversion of the signal current is completed and passes the drive current to the light emitting element through the channel in a state where the held voltage level is applied to the gate of the conversion use insulating gate type field effect transistor.