1-3hit |
Jin-Ho KIM Oh-Kyong KWON Byong-Deok CHOI
We present our recent results of the 10-bit data driver LSI for 42-inch diagonal TFT-LCD TV with full HD format. To develop data driver LSIs for a true 10-bit TFT-LCD TV with full HD (19201080) format, small chip area, low power consumption, and output uniformity between channels are key problems that must be solved. By applying a two-stage DAC which combines 8-bit resistor-string DAC and 2-bit binary weighted capacitor DAC, the area increase is limited to only 30% compared to the area of 8-bit resistor-string DAC. The output deviation between channels is successfully limited within 5 mV and the driver LSI with 414 outputs consumes the maximum total current of 16 mA when driving 42-inch HDTV panel. We confirmed that the picture with 10-bit shades of gray is much more natural than that with 8-bit shades of gray.
Ki-Soo NAM Pyong-Su KWAG Oh-Kyong KWON
A scalable DC model of lateral double diffused MOSFETs (LDMOSFETs) is presented in this paper. This model is based on physical analysis considering device geometry, carrier distributions, mobility degradation effect, and the effect of impact ionization. In this model, we divide the LDMOSFET into two regions to obtain the physical conduction model: one is channel region and the other is drift region. The channel region model is based on the BSIM3v3 model and the drift region employs voltage dependent resistance model considering the length of depleted region in the drift region. The modeling results are compared with measured I-V characteristics and the results show good agreements with the maximum error of 10% compared to the measured results of devices.
We present the 10-bit current driver LSI with 2-set current digital-to-analog converters (DACs) and output channel current sample and hold (S/H) circuits for large-size and high-resolution active matrix organic light emitting diode (AMOLED) display applications. This current driver LSI has 300 output channels and the output current ranges from 0 µA to 290 µA. The maximum output current level can be controlled by 2-bit control signals because the maximum output current level depends on display size and resolution. The chip was fabricated using 0.65µm BiCMOS process and characterized. The chip size is 16.8 mm3.6 mm. Experimental results show that the output current DNL is less than 0.4 LSB and that INL is less than 1.5 LSB. This is good enough to apply 15.5 inch WXGA (1280RGB768) AMOLED displays.