Abstract
In order to suppress the malfunction caused by the shift of the threshold voltage (VTH) of oxide thin film transistors (TFTs) to a negative value, double-gate TFTs are used in the shift register of the gate driving system to control VTH by adjusting the top gate bias. The proposed circuit detects the current consumption of the shift register and adjusts VTH so that the current consumption of the shift register is regulated within the desired value. The system includes a compensation algorithm, which can search for an optimized top gate bias in various circumstances such as process fluctuations and ambient temperature change. The proposed system provides a stable operation compared with a conventional structure especially at high temperature. Experimental results show that, in the conventional system without compensation, the output voltage of the shift register deteriorates at
$80\, {}^{\circ} {\rm C}$
and above, and the power consumption increases from 1.15 to 2.14 mW after 21600 s of continuous operation at
$60\, {}^{\circ} {\rm C}$
. On the other hand, the proposed system provides a stable gate output up to
$100\, {}^{\circ} {\rm C}$
and keeps the power consumption below 1.10 mW by adjusting the top gate bias responding to environment changes.
© 2016 IEEE
PDF Article
More Like This
Cited By
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Login to access Optica Member Subscription
Add to BibSonomy