Jong-Seon Kim

51.2: Reducing Gray-Level Response to One Frame: Dynamic Capacitance Compensation

A novel driving scheme, named Dynamic Capacitance Compensation (DCC), for active-matrix (AM) LCDs was developed. It takes the charge-&-hold nature of AM-LCDs into consideration to enhance the switching speed. By incorporating DCC and faster liquid crystal, a TFT-LCD whose response time was less than 10 ms for all gray levels with the on + off time of 8.4 ms was developed. DCC can be applied to any kind of LCD modes to reduce the gray response time to less than 1 frame.

An Integrated LDI with Readout Function for Touch-Sensor-Embedded Display Panels

An integrated mobile LDI with readout function is designed for touch sensor embedded display panels. This device not only drives the display panel but also senses either charge signals or current signals from the TFT sensor array with 8b resolution. The 22 times 1.8mm2 chip consumes 24mW, with 3mW required for the readout function

58.1: A 720-Channel LCD Source Driver with a 12-Bit Segmented R-C DAC

A 720-channel LCD source driver with a 12-bit segmented R-C DAC has been designed and fabricated by a 16V CMOS process. The proposed DAC consists of a conventional resistor string and a sample-and-hold buffer. DNL less than 0.3LSB and output voltage deviations less than 3mV were measured. Die area is 24.9mm2.

A Current Driver IC using a S/H for QVGA FullColor Active-Matrix Organic LED Mobile Displays

A current driver with 720 outputs for active-matrix organic LEDs uses a current-copier scheme to produce 64 gray levels with maximum 2% error from 10nA to 10uA on a 19.2 times 17.8mm2 die

43.2: A 400Mbps/ch SiDP Receiver for Mobile TFT-LCD Driver IC

A high speed serial interface receiver is realized in a 0.18um high voltage CMOS technology for a mobile 24-bit hVGA TFT-LCD driver (LDI) IC. The type of serial interface implemented is called Simple Display Port (SiDP) and is intended to replace the legacy RGB interface in the LDI ICs. The receiver consists of one clock and two data channels, and thereby reduces the number of signal lines going through the hinge of a mobile phone from 28 down to 6. All channels conform to Sub Low-Voltage Differential Signaling (SubLVDS) convention. The total transfer rate can be up to 800Mbps for two data channel. The current consumption was 5.4mA at the data rate of 600Mbps.

A 16.7M Color VGA Display Driver IC with Partial Graphic RAM and 500Mb/s/ch Serial Interface for Mobile a-Si TFT-LCDs

A single-chip 16.7M color VGA display driver IC featuring partial graphic RAM and 500Mb/s/ch high-speed serial interface has been developed. It pairs with a 1.98-inch mobile VGA amorphous-silicon TFT-LCD panel with 400 pixels/in. The IC has been fabricated in a 0.18 mum triple-well CMOS process with high-voltage transistors and occupies 23.0 times 2.5 mm2. The chip has two supplies, 1.8 and 2.75V, and uses a total of 45mW.

Prevention of adhesion failure of a W/TiN/Ti(Co) layer on SiO2

Abstract The delamination of W/TiN/Ti(Co) based metal lines was investigated. The adhesion failure was mostly induced by the formation of an interfacial layer between metal liner and inter-layer-dielectric (ILD) oxide. This interfacial layer could be a TiF x , formed by reaction between Ti and WF 6 during W deposition, or a ‘reacted layer’ caused by reaction between Ti (or Co) and ILD oxide at relatively high temperature. The quality of TiN barrier layer was a key factor influencing the formation of TiF x during W deposition. On the other hand, stripping of TiN/Ti (Co) liner after rapid thermal nitridation (RTN) was an essential process to prevent the reaction between the Ti (Co) and SiO 2 during the post high temperature processes. The RTN temperature should be lower than 600°C to minimize the interaction between the liner and ILD oxide. RF sputter cleaning after liner stripping was an effective method to remove the interfacial layer and to prevent the delamination of the metal layers.

P-38: 1Gbps/lane Low Overhead Clock-Shared Differential Signaling (CSDS) — An Efficient Interface for Large-Size TFT-LCDs

A clock-shared differential signaling (CSDS) scheme is newly proposed to support high resolution and large-Size TFT-LCDs with less than 3% overheads compared with transmitted data. CSDS adopts single-level, multi-dropped differential clocks which is shared among source driver ICs (CDs) and point-to-point connection for data lines. The protocol supporting CSDS makes the overhead of data transmission to be less than a few percent, which makes CSDS superior to other interfaces in terms of signal integrity, EMI, simple transmitter, and etc. It also supports flexible CD controls via just changing register values which are delivered by its protocol. And it is proved that CSDS supports 1.1Gbps per lane, which can cover next generation panels such as UD class.