JP2010040981A5

JP2010040981A5 -

Info

Publication number: JP2010040981A5
Application number: JP2008205425A
Authority: JP
Filing date: 2008-08-08
Publication date: 2011-09-15
Anticipated expiration: 2028-08-08

Claims

A first photoelectric conversion element;
A first amplifier circuit that outputs a first current obtained by amplifying an output current of the first photoelectric conversion element;
A second photoelectric conversion element having a spectral sensitivity characteristic different from that of the first photoelectric conversion element;
A second amplifier circuit that outputs a second current obtained by amplifying the output current of the second photoelectric conversion element;
The first charge is accumulated according to the first potential supplied through the first switch, and the first charge is discharged according to the first current supplied through the second switch. A first capacitive element that
A first comparator which compares the potential and the second potential of one electrode of the first capacitor,
The first clock generation circuit that forms play the first clock signal,
A first counter circuit for outputting a first count value obtained by counting up the first clock signal,
A latch circuit that latches the first count value in accordance with a signal output from the first comparator, and outputs the latched first count value as a first digital signal ;
The second electric charge is accumulated according to the first electric potential supplied through the third switch, and the second electric charge is accumulated according to the second electric current supplied through the fourth switch. A second capacitive element for discharging;
A second comparator for comparing the potential of one electrode of the second capacitive element with the second potential;
A second clock generation circuit for generating a second clock signal;
A second counter circuit for outputting a second count value obtained by counting up the second clock signal;
A latch circuit that latches the second count value in accordance with a signal output from the second comparator and outputs the latched second count value as a second digital signal;
A photoelectric conversion device comprising: a subtracting circuit for outputting a difference between the first digital signal and the second digital signal .

In claim 1,
After the first charge is accumulated in the first capacitor element, the first counter circuit is reset,
The photoelectric conversion device, wherein the second counter circuit is reset after the second electric charge is accumulated in the second capacitor element.

In claim 1 or claim 2,
The first latch circuit latches the first count value when the first count value reaches a maximum value;
The photoelectric conversion device, wherein the second latch circuit latches the second count value when the second count value reaches a maximum value.

A first photoelectric conversion element;
A first amplifier circuit that outputs a first current obtained by amplifying an output current of the first photoelectric conversion element;
A second photoelectric conversion element having a spectral sensitivity characteristic different from that of the first photoelectric conversion element;
A second amplifier circuit that outputs a second current obtained by amplifying the output current of the second photoelectric conversion element;
A subtraction circuit you output a difference of said first current and said second current as a voltage value,
A voltage-current converter that outputs a third current according to the voltage value;
A capacitive element that accumulates electric charge according to a first potential supplied via a first switch and discharges the electric charge according to the third current supplied via a second switch;
A comparator for comparing the one and second potentials of electrodes of the capacitor,
And a clock generation circuit that forms the clock signal raw,
A counter circuit for outputting a count value obtained by counting up said clock signal,
And a latch circuit that latches and outputs the count value in accordance with a signal output from the comparator.

A first photoelectric conversion element;
A first amplifier circuit that outputs a first current obtained by amplifying an output current of the first photoelectric conversion element;
A second photoelectric conversion element having a spectral sensitivity characteristic different from that of the first photoelectric conversion element;
A second amplifier circuit that outputs a second current obtained by amplifying the output current of the second photoelectric conversion element;
A current mirror circuit for converting the second current, to flow toward the first amplifier circuit,
A capacitive element that accumulates charges according to a first potential supplied via a first switch and discharges the charges according to a third current supplied via a second switch;
A comparator for comparing the one and second potentials of electrodes of the capacitor,
And a clock generation circuit that forms the clock signal raw,
A counter circuit for outputting a count value obtained by counting up said clock signal,
Depending on the signal output from the comparator, have a, a latch circuit configured to latch the count value,
The photoelectric conversion device according to claim 3, wherein the third current is a difference between the first current and the second current converted by the current mirror circuit .

In claim 4 or claim 5,
The photoelectric conversion device, wherein the counter circuit is reset after the charge is accumulated in the capacitor.

In any one of Claims 4 thru | or 6,
The latch circuit latches the count value when the count value reaches a maximum value.

In any one of Claims 1 thru | or 7 ,
The photoelectric conversion device, wherein the first photoelectric conversion element and the second photoelectric conversion element is one formed on a single crystal silicon substrate.

In any one of Claims 1 thru | or 8 ,
The photoelectric conversion device, wherein the first amplifier circuit and the second amplifier circuit have a function of switching an amplification factor according to illuminance .

In any one of Claims 1 thru | or 9,
Each of the first amplifier circuit and the second amplifier circuit has a plurality of amplifier circuits,
In each of the first amplifier circuit and the second amplifier circuit,
The amplification factors of the plurality of amplifier circuits are different from each other,
The plurality of amplifier circuits are switched in accordance with illuminance.

In any one of Claims 1 thru | or 10 ,
It said first photoelectric conversion element and the second photoelectric conversion element, a photoelectric conversion device characterized by having an opening of the same size.

In any one of Claims 1 thru | or 11 ,
The second on the side where the light of the photoelectric conversion element is incident, the photoelectric conversion device characterized by infrared light transmitting filter is eclipsed set.

In any one of Claims 1 to 12,
The photoelectric conversion device, wherein the second potential is lower than the first potential.

An electronic apparatus characterized by comprising a photoelectric conversion device according to claim 1 to claim 13.