# US 2019/0172387 A1 · Source driver and display apparatus including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0172387 A1 - Document ID: US20190172387A1 - Status: Published application - Kind: A1 - Application number: 16/044,348 - Filed: 2018-07-24 - Published: 2019-06-06 - Earliest claimed: 2017-12-06 - Assignees: DB HiTek Co., Ltd. - Applicants: DB HiTek Co., Ltd. - Inventors: Yong Ho CHOI - Web page: https://patentgrep.com/patent/US20190172387A1 ## CPC - G09G 3/22: using controlled light sources - G09G 3/3275: Details of drivers for data electrodes - G09G 3/3611: {Control of matrices with row and column drivers} - G09G 3/3688: {suitable for active matrices only} - H03M 1/66: Digital/analogue converters ({H03M1/001 – } H03M1/10 take precedence) - G09G 2310/027: Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters - G09G 2310/0275: Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current - G09G 2310/0286: Details of a shift registers arranged for use in a driving circuit - G09G 2310/0289: Details of voltage level shifters arranged for use in a driving circuit - G09G 2330/04: Display protection - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract A source driver includes a digital-to-analog converter configured to receive a data signal, convert the received data signal into an analog signal, and output the analog signal, an output unit including amplifiers configured to amplify the analog signal, a control signal provision unit configured to output at least one control signal based on or in response to a first bias signal, at least one level shifter configured to shift a level of the control signal(s) based on or in response to a second bias signal having a higher voltage than the first bias signal and output at least one level-shifted control signal, and a protector configured to detect a voltage of the first bias signal and turn off the amplifiers and the level shifter when the detected voltage of the first bias signal is less than a predetermined reference voltage. ## Claims ### Claim 1 A source driver, comprising: a digital-to-analog converter configured to receive a data signal, convert the received data signal into an analog signal, and output the analog signal; an output unit including amplifiers configured to amplify the analog signal; a control signal provision unit configured to output at least one control signal based on or in response to a first bias signal; at least one level shifter configured to shift a level of the at least one control signal based on or in response to a second bias signal having a higher voltage than the first bias signal, and output at least one level-shifted control signal; and a protector configured to detect a voltage of the first bias signal and turn off the amplifiers and the level shifter when the detected voltage of the first bias signal is less than a predetermined reference voltage. ### Claim 2 (depends on 1) The source driver according to claim 1, wherein the protector detects the voltage of the first bias signal and cuts off the voltages to one or more of the amplifiers and corresponding ones of the level shifters when the detected voltage of the first bias signal is less than the predetermined reference voltage. ### Claim 3 (depends on 1) The source driver according to claim 1, further comprising a multiplexer configured to selectively output the amplified analog signals from the amplifiers to output lines based on or in response to output of the at least one level shifter, wherein the protector outputs a first deactivation signal configured to turn off the multiplexer when the detected voltage of the first bias signal is less than the predetermined reference voltage. ### Claim 4 (depends on 1) The source driver according to claim 1, further comprising a charge sharing switch configured to share a charge on the output lines corresponding to the amplifiers, wherein the protector outputs a second deactivation signal configured to turn off the charge sharing switch when the detected voltage of the first bias signal is less than the predetermined reference voltage. ### Claim 5 (depends on 1) The source driver according to claim 1, wherein the protector turns on the amplifiers and the level shifter when the detected voltage of the first bias signal is equal to or greater than the predetermined reference voltage. ### Claim 6 (depends on 3) The source driver according to claim 3, wherein the protector does not output the first deactivation signal when the detected voltage of the first bias signal is equal to or greater than the predetermined reference voltage. ### Claim 7 (depends on 4) The source driver according to claim 4, wherein the protector does not output the second deactivation signal when the detected voltage of the first bias signal is equal to or greater than the predetermined reference voltage. ### Claim 8 A source driver comprising: a digital-to-analog converter configured to receive a data signal, convert the received data signal into an analog signal, and output the analog signal; amplifiers configured to amplify the analog signal; a control signal provision unit configured to output a first control signal and a second control signal based on or in response to a first bias signal; a first level shifter configured to shift a level of the first control signal based on or in response to a second bias signal having a voltage greater than that of the first bias signal and to output a level-shifted first control signal; a second level shifter configured to shift a level of the second control signal based on or in response to the second bias signal and output a level-shifted second control signal; output lines corresponding to the amplifiers; a multiplexer configured to selectively output the amplified analog signals from the amplifiers to the output lines based on or in response to output of the first level shifter; a charge sharing switch connected between the output lines and controlled based on or in response to output of the second level shifter; and a protector configured to detect a voltage of the first bias signal and to turn off the amplifiers, the first level shifter and the second level shifter and output a first deactivation signal configured to turn off the multiplexer and a second deactivation signal configured to turn off the charge sharing switch, when the detected voltage of the first bias signal is less than a predetermined reference voltage. ### Claim 9 (depends on 8) The source driver according to claim 8, wherein the protector outputs a first signal configured to turn off the amplifiers and a second signal configured to turn off the first and second level shifters when the detected voltage of the first bias signal is less than the predetermined reference voltage. ### Claim 10 (depends on 8) The source driver according to claim 8, wherein the protector includes: a voltage detector configured to output a detection signal based on the voltage of the first bias signal; a voltage cutoff signal generator configured to output a first signal configured to turn off the amplifiers and a second signal configured to turn off the first and second level shifters based on or in response to the detection signal; and a deactivation signal generator configured to output the first deactivation signal and the second deactivation signal based on or in response to the detection signal. ### Claim 11 (depends on 10) The source driver according to claim 10, wherein the voltage detector includes: a first transistor including a first gate configured to receive the first bias signal and source and drain terminals connected between a first node and the ground; and a resistor configured to receive the second bias signal at one end and the connected to the first node at another end, and the detection signal is output from the first node. ### Claim 12 (depends on 10) The source driver according to claim 10, wherein the voltage detector includes: a transistor including a gate configured to receive the first bias signal and a source and drain terminals connected between a first node and the ground; a resistor including one end configured to receive the second bias signal at one end and connected to the first node at another end; and an inverter connected to the first node, and the detection signal is output from the first inverter. ### Claim 13 (depends on 10) The source driver according to claim 10, wherein the deactivation signal generator includes a first deactivation signal generator including a first transistor including a first gate, a first source configured to receive the second bias signal, and a first drain connected to a second node and a second transistor including a second gate, a second drain connected to the second node, and a second source connected to the ground, and wherein the voltage cutoff signal generator outputs a first gate control signal configured to control the first gate and a second control signal configured to control the second gate. ### Claim 14 (depends on 13) The source driver according to claim 13, wherein the second node is connected to an output terminal of the first level shifter. ### Claim 15 (depends on 14) The source driver according to claim 14, wherein the first deactivation signal generator further includes a second inverter connected to the second node. ### Claim 16 (depends on 13) The source driver according to claim 13, wherein the deactivation signal generator further includes a second deactivation signal generator including a third transistor including a third gate, a third source configured to receive the second bias signal, and a third drain connected to a third node and a fourth transistor including a fourth gate, a fourth drain connected to the third node, and a fourth source connected to the ground, and wherein the voltage cutoff signal generator outputs a third gate control signal configured to control the third gate and a fourth gate control signal configured to control the fourth gate. ### Claim 17 (depends on 16) The source driver according to claim 16, wherein the third node is connected to an output terminal of the third level shifter. ### Claim 18 (depends on 17) The source driver according to claim 17, wherein the second deactivation signal generator further includes a third inverter connected to the third node. ### Claim 19 (depends on 8) The source driver according to claim 8, wherein the protector turns on the amplifiers and the first and second level shifters and does not output the first and second deactivation signals when the detected voltage of the first bias signal is equal to or greater than the predetermined reference voltage. ### Claim 20 (depends on 1) A display device comprising: a display panel including gate lines, data lines, and pixels connected to the gate lines and the data lines in a matrix including rows and columns; the source driver of claim 1, wherein the source driver is configured to drive the data lines; and a gate driver configured to drive the gate lines.