US 12,067,912 B2
Display driver and display module
Kazuaki Tanaka, Nagano (JP)
Assigned to SEIKO EPSON CORPORATION, (JP)
Filed by SEIKO EPSON CORPORATION, Tokyo (JP)
Filed on Aug. 30, 2022, as Appl. No. 17/898,807.
Claims priority of application No. 2021-141124 (JP), filed on Aug. 31, 2021.
Prior Publication US 2023/0063763 A1, Mar. 2, 2023
Int. Cl. G09G 3/00 (2006.01); G02F 1/133 (2006.01); G09G 3/36 (2006.01); H05K 9/00 (2006.01)
CPC G09G 3/006 (2013.01) [G02F 1/13306 (2013.01); G09G 3/3648 (2013.01); H05K 9/0067 (2013.01); G02F 2202/22 (2013.01); G09G 2330/04 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A display driver comprising:
a driver circuit that drives an electro-optical panel;
an output terminal that outputs an output signal from the driver circuit;
an output line that couples the output of the driver circuit and the output terminal; and
an inspection circuit that detects an abnormality of the output signal output by the driver circuit to the output line by monitoring a voltage of the output signal, wherein
the inspection circuit determines whether the voltage of the output signal is abnormal by comparing the voltage of the output signal with a first reference voltage and a second reference voltage in each given cycle,
a value of the first reference voltage is higher than a value of the second reference voltage, and
the inspection circuit includes:
a reference voltage generation circuit that generates a plurality of voltages and that outputs the first and second reference voltages selected from the plurality of voltages in each given cycle; and
a comparison circuit that:
compares whether the voltage of the output signal is between the first and second reference voltages;
determines that the voltage of the output signal is abnormal when the voltage of the output signal is between the first and second reference voltages;
determines that the voltage of the output signal is normal when the voltage of the output signal deviates from a range between the first and second reference voltages; and
provides abnormality information including a comparison result to a control circuit that controls the display driver.