초록 ▼

The semiconductor device includes a first photodiode, a second photodiode which is shielded from light, a first circuit group including a voltage follower circuit, a second circuit group, and a compensation circuit, in which an output from the first photodiode is inputted to the voltage follower cir

The semiconductor device includes a first photodiode, a second photodiode which is shielded from light, a first circuit group including a voltage follower circuit, a second circuit group, and a compensation circuit, in which an output from the first photodiode is inputted to the voltage follower circuit of the first circuit group, an output from the first circuit group is inputted to the compensation circuit, and an output from the second photodiode is inputted to the compensation circuit through the second circuit group. By adding or subtracting these inputs in the compensation circuit, an output fluctuation due to temperature of the first photodiode is removed. Note that a reference potential is supplied to the first photodiode so that an open circuit voltage is outputted, and a potential is supplied to the second photodiode so that a forward bias is applied to the second photodiode.

대표청구항 ▼

What is claimed is: 1. A semiconductor device comprising: a first photodiode which detects light; a second photodiode; a light shielding film for shielding the second photodiode from light; a first circuit group including a voltage follower circuit to which an output from one terminal of the first

What is claimed is: 1. A semiconductor device comprising: a first photodiode which detects light; a second photodiode; a light shielding film for shielding the second photodiode from light; a first circuit group including a voltage follower circuit to which an output from one terminal of the first photodiode is inputted; a second circuit group including a voltage regulator circuit for adjusting an output obtained from one terminal of the second photodiode to a voltage based on a voltage under a predetermined temperature; and a compensation circuit to which outputs from the first circuit group and the second circuit group are inputted, the compensation circuit adding or subtracting each of the outputs, wherein a reference potential is supplied to the other terminal of the first photodiode; and wherein a potential is supplied to the other terminal of the second photodiode so that a forward bias is applied to the second photodiode. 2. The semiconductor device according to claim 1, wherein each of the first photodiode and the second photodiode comprises an n-type semiconductor layer and a p-type semiconductor layer; wherein one terminal of the first photodiode and the other terminal of the second photodiode are electrically connected to the p-type semiconductor layer; and wherein the other terminal of the first photodiode and one terminal of the second photodiode are electrically connected to the n-type semiconductor layer. 3. The semiconductor device according to claim 1, wherein one terminal of the first photodiode has a higher potential than the other terminal thereof when light is delivered. 4. The semiconductor device according to claim 1, wherein the second circuit group comprises a function of amplifying or inverting an output obtained from one terminal of the second photodiode. 5. The semiconductor device according to claim 1, wherein each of the first circuit group and the second circuit group comprises an operational amplifier. 6. The semiconductor device according to claim 1, wherein each of the first circuit group and the second circuit group comprises a plurality of thin film transistors. 7. An electronic device comprising the semiconductor device according to claim 1. 8. A semiconductor device comprising: a first photodiode which detects light; a second photodiode; a light shielding film for shielding the second photodiode from light; a first circuit group including a voltage follower circuit to which an output from one terminal of the first photodiode is inputted; a second circuit group to which an output obtained from one terminal of the second photodiode is inputted, the second circuit group including an inverting amplifier circuit, an inverter circuit, and a voltage regulator circuit for adjusting an output from the first circuit group to a voltage based on a voltage under a predetermined temperature; and a compensation circuit to which outputs from the first circuit group and the second circuit group are inputted, the compensation circuit adding or subtracting each of the outputs, wherein a reference potential is supplied to the other terminal of the first photodiode; wherein a potential is supplied to the other terminal of the second photodiode so that a forward bias is applied to the second photodiode; and wherein one terminal of the first photodiode has a higher potential than the other terminal thereof when light is delivered. 9. The semiconductor device according to claim 8, wherein each of the first photodiode and the second photodiode comprises a p-type semiconductor layer, an n-type semiconductor layer, and an i-type semiconductor layer provided between the p-type semiconductor layer and the n-type semiconductor layer. 10. The semiconductor device according to claim 8, wherein each of the first circuit group and the second circuit group comprises an operational amplifier. 11. The semiconductor device according to claim 8, wherein each of the first circuit group and the second circuit group comprises a plurality of thin film transistors. 12. An electronic device comprising the semiconductor device according to claim 8. 13. A semiconductor device comprising: a first photodiode which detects light; a second photodiode; a light shielding film for shielding the second photodiode; a first circuit group including a voltage follower circuit to which an output from one terminal of the first photodiode is inputted; a second circuit group including: an inverting amplifier circuit to which an output obtained from one terminal of the second photodiode is inputted, an inverter circuit, and a voltage regulator circuit for adjusting an output from the first circuit group to a voltage based on a voltage under a predetermined temperature; and an adding circuit to which an output from the first circuit group and an output from the second circuit group are inputted, wherein a reference potential is supplied to the other terminal of the first photodiode; wherein a potential is supplied to the other terminal of the second photodiode so that a forward bias is applied to the second photodiode; and wherein one terminal of the first photodiode has a higher potential than the other terminal when light is delivered. 14. The semiconductor device according to claim 13, wherein each of the first photodiode and the second photodiode comprises a p-type semiconductor layer, an n-type semiconductor layer, and an i-type semiconductor layer provided between the p-type semiconductor layer and the n-type semiconductor layer. 15. The semiconductor device according to claim 13, wherein each of the first circuit group and the second circuit group comprises an operational amplifier. 16. The semiconductor device according to claims 13, wherein each of the first circuit group and the second circuit group comprises a plurality of thin film transistors. 17. An electronic device comprising the semiconductor device according to claim 13. 18. A semiconductor device comprising: a first photodiode to detect light, the first photodiode including a first terminal and a second terminal; a second photodiode including a first terminal and a second terminal; a light shielding film for shielding the second photodiode from light; a first circuit group including a voltage follower circuit and connected to the first terminal of the first photodiode, wherein an output from the first terminal is inputted to the first terminal of the first photodiode; a second circuit group including a voltage regulator circuit and connected to the first terminal of the second photodiode, wherein an output from the first terminal of the second photodiode is adjusted to a voltage which uses a voltage under a predetermined temperature as a reference; and a compensation circuit connected to the first and second circuit groups, wherein the fluctuation of the output from the first terminal of the first photodiode is compensated. 19. The semiconductor device according to claim 18, wherein a reference potential is supplied to the second terminal of the first photodiode; and wherein a potential is supplied to the second terminal of the second photodiode so that a forward bias is applied to the second photodiode. 20. The semiconductor device according to claim 18, wherein each of the first photodiode and the second photodiode comprises a p-type semiconductor layer, an n-type semiconductor layer, and an i-type semiconductor layer provided between the p-type semiconductor layer and the n-type semiconductor layer. 21. The semiconductor device according to claim 18, wherein each of the first circuit group and the second circuit group comprises an operational amplifier. 22. The semiconductor device according to claims 18, wherein each of the first circuit group and the second circuit group comprises a plurality of thin film transistors. 23. An electronic device comprising the semiconductor device according to claim 18.