JPS6282781A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To prevent the generation of noise resulting from a rise and a fall of a start pulse and an end pule of an output signal by providing dummy terminals respectively in a start pulse input terminal and an end pulse output terminal of a drive circuit. CONSTITUTION:A dummy terminal 116 is disposed to a start pulse input terminal 11 and a dummy terminal 118 is disposed to an end pulse output terminal 117, and opposite phase signals of a start pulse and an end pulse are added to the dummy terminals, respectively. Therefore, noise generated on the rise of the start pulse and the end pulse signals can be cancelled by the fall of the opposite phase signal and noise generated on the fall of the start pulse an the end pulse signals can be cancelled by the rise of the opposite phase signal. Thereby, an output signal waveform having a normal form without a noise component is outputted during a selecting period of the start pulse and immediately thereafter and during the selecting period of the end pulse and immediately thereafter.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to noise elimination in a solid-state imaging device with a built-in drive circuit.

[Summary of the invention]

The present invention provides a solid-state imaging device with a built-in drive circuit, in which a dummy terminal is provided for each of the start pulse input terminal and end pulse output terminal of the drive circuit, and the dummy terminals are provided with a pulse with a reverse phase of the start pulse and a pulse with a reverse phase with the end pulse, respectively. By adding , the noise caused by the start pulse and the rising and falling edges of the output signal of the solid-state imaging device is eliminated.

[Conventional technology]

FIG. 2 shows a conventional solid-state imaging device with a built-in drive circuit. In the figure, 201 is a drive circuit, 202 to 205 are output terminals of the drive circuit 201, and 206 to 209 are analog switches.When the potential of these switching control input terminals 202 to 205 is high, the analog switches are conductive. shall be taken as a thing.

210 to 213 are photoelectric conversion elements, 214 is an output signal line, 215 is a start pulse input terminal of the drive circuit 201,
216 is an end pulse output terminal, 217 is a stray capacitance between the start pulse input terminal 215 and the output signal terminal 214,
218 is the end pulse output terminal 216 and the output signal line 21
The stray capacitance is between 4 and 4.

FIG. 3 shows an example of driving waveforms of the conventional solid-state imaging device shown in FIG.

In the figure, 301 is a start pulse voltage waveform, which is input to the start pulse input terminal 215. 302,3
03, 304 and 505 are the voltage waveforms applied to the output terminals 202, 203, 204 and 205 of the drive circuit 201, respectively, 306 is the voltage waveform output to the end pulse output terminal 216, and 307 is the voltage waveform output to the output signal @214. [Problem and purpose to be solved by the invention] However, in the above-mentioned conventional technology, the output signal line is However, there is a problem in that noise is generated in the 214.

In FIG. 5, noise caused by the start pulse at times t and t, and the end pulse at times t6 and t7 is generated as shown in the output signal current waveform 307, and the noise is generated as shown in the output signal current waveform 307. The output signal will be different from the original data. This can be solved by not reading the output signal during the start pulse selection period and immediately after it (period tl to t in Figure 3) and by shifting the end pulse selection period (from time t onwards in Figure 3). This causes problems such as a narrowing of the effective area of the solid-state image sensor chip and inconvenience when connecting a plurality of solid-state image sensor chips in series.

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and its purpose is to prevent noise caused by the rising and falling edges of the start pulse and end pulse from occurring in the output signal, and to minimize the chip effective area. The object of the present invention is to realize a large solid-state imaging device with a built-in high-performance drive circuit that can be connected in series.

[Means for solving problems]

The solid-state imaging device of the present invention is characterized in that dummy terminals are provided for each of the start pulse input terminal and end pulse output terminal of one drive circuit.

[For production]

According to the above configuration of the present invention, a dummy terminal is provided for each of the start pulse input terminal and the end pulse output terminal of the solid-state imaging device with a built-in drive circuit, and the dummy terminal is provided with a pulse with a reverse phase of the start pulse and an end pulse, respectively. By adding a pulse with an opposite phase to the pulse, it is possible to eliminate noise caused by the start pulse and end pulse that have been generated in the output signal of the solid-state imaging device. Therefore, a normal output signal can be obtained even during the start pulse selection period and the end pulse selection period. Therefore, a drive circuit for shifting the selection period of the start pulse and end pulse from the output signal is not required, and a solid-state imaging device with a built-in high-performance drive circuit, which has a large effective chip area and can connect multiple devices, is realized. .

〔Example〕

FIG. 1 shows a circuit diagram of a solid-state imaging device according to an embodiment of the present invention, in which dummy terminals are provided for the start pulse input terminal and the end pulse output terminal. In the figure, 101 is a drive circuit, 102 to 105 are output terminals of the drive circuit 101,
106 to 109 are analog switches, 110 to 11
5 is a photoelectric conversion element, 114 is an output signal line, 115 is a start pulse input terminal, 116 is a dummy terminal provided for the start pulse input terminal 115, 117 is an end pulse output terminal, and 118 is provided for the end pulse output terminal 117. This is a dummy terminal.

FIG. 4 shows an example of a driving waveform of the image pickup device shown in FIG. In the figure, 401 is a start pulse voltage waveform, which is applied to the start pulse input terminal 115. 402 is a signal having an opposite phase to the start pulse 401, and is applied to a dummy terminal 116 provided for 115. 405, 404, 405 and 406 are the output terminals 102 and 406 of the drive circuit 101, respectively.
Voltage waveform output to 103, 104 and 105, 40
7 is the end pulse voltage waveform, end pulse output terminal 1
0408 outputted to the end pulse 407 is a signal having a phase opposite to that of the end pulse 407, and is inputted to a dummy terminal 118 provided for the end pulse output terminal 117.

409 is the output signal current waveform output to the output signal line 114. Figure 5 shows a circuit diagram of a solid-state imaging device in which the dummy terminal and the start pulse and end pulse terminals are connected by an inverter according to an embodiment of the present invention. . In this figure, the same symbols as in FIG. 1 represent the same things as in FIG. 1. 501 and 502
is an inverter provided in the same solid-state image sensor chip, and the start pulse signal input to the start pulse input terminal 115 is inverted by the inverter 501 and applied to the dummy terminal 116.Similarly, the start pulse signal input to the start pulse input terminal 115 is
The end pulse signal outputted to the terminal 7 is inverted by the inverter 502 and applied to the dummy terminal 118.

FIG. 6 shows a circuit diagram of an application example of the present invention in which two solid-state imaging devices provided with dummy terminals are connected. In the figure, 601 is a drive circuit, and 602 to 604 are drive circuits 6.
01 output terminal, 605 to 607 are analog switches, 608 to 610 are photoelectric conversion elements, 611 to 616
is the positive power supply of the photoelectric conversion element, 614 is the start pulse input terminal, 615 is the dummy terminal provided for 614, 616
is an end pulse output terminal, 617 is a dummy terminal provided for 616, 618 and 619 are inverters, and 620
is the output signal line. A first solid-state imaging device 641 is formed in steps 601 to 620.

Similarly, 621 is a drive circuit, 622 to 624 are output terminals of 621, 625 to 627 are analog switches, and 62
8 to 630 are photoelectric conversion elements, 631 to 633 are positive power supplies, 634 is a start pulse input terminal, 635 is a dummy terminal, 636 is an end pulse output terminal, 637 is a dummy terminal, 638 and 639 are inverters, and 640 is an output The second solid-state imaging device 64 is connected to signal lines 621 to 640.
2 is formed. 643 is the end pulse output terminal 616 of the first solid-state imaging device 641 and the second solid-state imaging device 64
Wiring connecting the start pulse input terminal 634 of No. 2,
644 is an output signal terminal of the sixth rotating body imaging device.

FIG. 7 is an example of a driving waveform of the imaging device shown in FIG. 6. Reference numeral 701 is a start pulse voltage waveform, which is input to the start pulse input terminal 614 of the first solid-state imaging device. 702 is a reverse phase signal of the start pulse, which is passed through the inverter 618.
This is a voltage waveform applied to the dummy terminal 615. 703
．． 704, 705 are voltage waveforms output to 602, 605, and 604, respectively, 706 is a voltage waveform output to the end pulse output terminal of the first solid-state imaging device, and the start pulse input terminal 654 of the second solid-state imaging device. is input to. 707 is the voltage waveform of the signal that is inverted by inverters 619 and 6'58 and applied to the dummy terminals 617 and 635, and 708, 709.710 are the voltage waveforms of the signals 622.
Voltage waveform output to 623.624, 711 and 71
2 is the voltage waveform of the signal output to the end pulse output terminal 636 and the dummy terminal 637, and 713 is the current waveform of the output signal output to the output signal terminal 644.

〔Effect of the invention〕

In the first drawing body imaging device, a dummy terminal 116 is provided for the start pulse input terminal 115, a dummy terminal 118 is provided for the end pulse output terminal 117, and reverse phase signals of the start pulse and the end pulse are applied to the dummy terminals, respectively. There is. Therefore, the noise that occurs when the start pulse and end pulse signals rise can be canceled by the fall of the negative phase signal, and the noise that occurs when the start pulse and end pulse signals fall can be canceled by the rise of the negative phase signal. Therefore, as shown at 409, the output signal waveform is normal and free of noise components during the start pulse selection period and immediately after, and during the end pulse selection period and immediately after.

In the fifth figure image pickup device, the start pulse input terminal and the dummy terminal, and the end pulse output terminal and the dummy terminal are connected by an inverter provided inside the chip. Therefore, the dummy terminal 116 is automatically supplied with a reverse phase signal of the start pulse, and the dummy terminal 118 is automatically supplied with a reverse phase signal of the end pulse. Therefore, when using a solid-state imaging device as shown in the figure, external signals (start pulse reverse phase signal and end pulse reverse phase signal) necessary for the first drawing body imaging device
is no longer necessary, and the number of mounting terminals has also decreased! The solid-state imaging device shown in FIG. 6 is an example in which two solid-state imaging devices of the present invention are connected. As mentioned above, since the solid-state imaging device of the present invention can eliminate the noise caused by the start pulse and end pulse with just one device, even if multiple devices are connected, the output signal due to the noise caused by the start pulse and end pulse will be lost near the connection part. Since no non-uniformity occurs, the output signal waveform is uniform over all bits as shown in 713.It is still necessary to shift the selection period of the start pulse and end pulse and the output signal waveform as described above. This eliminates the need for a drive circuit, which simplifies the layout around the connection area and allows for smoother chip connections.

As described above, by using the present invention, the output signal waveform is uniform over all bits, the effective chip area is large,
A solid-state imaging device with a built-in drive circuit that can be easily connected to multiple devices is realized.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a solid-state imaging device according to an embodiment of the present invention, in which dummy terminals are provided for each of the start pulse input terminal and the end pulse output terminal. 101...Drive circuit 115...Start pulse input terminal 116...
...Dummy terminal 117...End pulse output terminal 118...
...Dummy terminal FIG. 2 is a circuit diagram of a conventional solid-state imaging device. FIG. 5 is a drive waveform diagram of the conventional solid-state imaging device shown in FIG. FIG. 4 is a drive waveform diagram of the surface body imaging device shown in FIG. 1. FIG. 5 is a circuit diagram of a solid-state imaging device in which a dummy terminal, a start pulse terminal, and an end pulse terminal are connected by an inverter, according to an embodiment of the present invention. 501 and 502... Inverter FIG. 6 is an application example of the present invention, and is a circuit diagram when two solid-state imaging devices provided with dummy terminals are connected. 641...First solid-state imaging device 642...
...Second solid-state imaging device FIG. 7 is a drive waveform diagram of the two-piece connected solid-state imaging device shown in FIG. 6. that's all

Claims (2)

[Claims] (1) In a solid-state imaging device consisting of a plurality of photoelectric conversion elements, an analog switch connected in series to the photoelectric conversion elements, and a drive circuit, for the start pulse input terminal and end pulse output terminal of the drive circuit, A solid-state imaging device characterized in that each is provided with a dummy terminal. (2) The solid-state imaging device according to claim 1, wherein the dummy terminal is connected to a start pulse input terminal and an end pulse output terminal, respectively, via an inverter provided on the same chip. Device.