| US 7,348,533 B2 | ||
| Unit pixel of CMOS image sensor | ||
| Joo Yul Ko, Kyungki-Do (Korea, Republic of); Won Tae Choi, Kyungki-Do (Korea, Republic of); Deuk Hee Park, Seoul (Korea, Republic of); and Shin Jae Kang, Kyungki-Do (Korea, Republic of) | ||
| Assigned to Samsung Electro-Mechanics Co., Ltd., Kyungki-Do (Korea, Republic of) | ||
| Filed on Jul. 17, 2006, as Appl. No. 11/458,018. | ||
| Claims priority of application No. 10-2005-0067876 (KR), filed on Jul. 26, 2005. | ||
| Prior Publication US 2007/0023612 A1, Feb. 01, 2007 | ||
| Int. Cl. H01L 27/00 (2006.01) | ||
| U.S. Cl. 250—208.1 [348/243; 348/308; 257/292] | 7 Claims |
| 1. A unit pixel of a complementary metal oxide semiconductor image sensor comprising:
a photo diode for generating and storing a charge in accordance with a received light amount;
a drive transistor having a gate for receiving the charge from the photo diode and a source for outputting the received charge
as a source value and a drain to which a power voltage is applied;
a saturation detector for receiving source voltage from the drive transistor and judging the drive transistor saturated if
the source voltage is smaller than a preset reference voltage; and
a switch for connecting or disconnecting between the power voltage and the gate of the drive transistor in response to the
judgment of the saturation detector.
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