US 12,136,384 B2
Light-emitting element driving device
Yoshikazu Sasaki, Kyoto (JP); and Kenji Yamada, Kyoto (JP)
Assigned to Rohm Co., Ltd., Kyoto (JP)
Appl. No. 18/272,654
Filed by Rohm Co., Ltd., Kyoto (JP)
PCT Filed Nov. 18, 2021, PCT No. PCT/JP2021/042452
§ 371(c)(1), (2) Date Jul. 17, 2023,
PCT Pub. No. WO2022/153668, PCT Pub. Date Jul. 21, 2022.
Claims priority of application No. 2021-005610 (JP), filed on Jan. 18, 2021.
Prior Publication US 2024/0078966 A1, Mar. 7, 2024
Int. Cl. G09G 3/32 (2016.01); G09G 3/00 (2006.01)
CPC G09G 3/32 (2013.01) [G09G 3/006 (2013.01); G09G 2310/08 (2013.01); G09G 2330/08 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A light-emitting element driving device comprising connection terminals corresponding to a plurality of channels, the connection terminals being configured to be connectable to light-emitting units having one or more light-emitting elements, the light-emitting element driving device being configured to be capable of supplying driving currents to the light-emitting units via the connection terminals individually for each of the channels,
wherein the light-emitting element driving device includes a particular fault sensor configured to be capable of executing a sensing process for sensing a particular fault during a non-supply period of the driving currents to the light-emitting units, the particular fault being an abnormality in a resistance value between two connection terminals adjacent to each other among the plurality of connection terminals,
the particular fault sensor includes:
a pull-up circuit configured to be capable of feeding a pull-up current toward the connection terminals individually for each of the channels; and
a comparator configured to compare a voltage at the connection terminals with a predetermined judgment voltage,
the sensing process includes:
a first comparison process by which, with the pull-up current fed toward one of the two connection terminals, a voltage at another of the two connection terminals is compared with the judgment voltage; and
a second comparison process by which, with the pull-up current fed toward the other of the two connection terminals, a voltage at the one of the two connection terminals is compared with the judgment voltage, and
based on results of the first and second comparison processes, the particular fault sensor senses presence or absence of the particular fault at the two connection terminals.