Light-emitting element drive circuit and portable electronic instrument
AssigneeSharp Kabushiki Kaisha
InventorsTAKAYUKI SHIMIZU, YOSHIKI IKUTA, HIDEKI SATO, TAKUMA HIRAMATSU
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Abstract
There is provided a VCSEL drive circuit that causes a VCSEL to emit pulsed light in a light emission period, including a drive adjustment unit that adjust a first voltage which is a voltage of drains of a PMOS transistor and an NMOS transistor in a constant current circuit and a second voltage which is a voltage of a drain of an NMOS transistor that drives the VCSEL to be the same voltage in a pre-light emission period before the light emission period.
Claims6
A light-emitting element drive circuit that causes a light-emitting element to emit pulsed light in a light emission period, the circuit comprising:
- a drive adjustment unit that adjusts a first voltage which is a voltage of a drain of a first transistor included in a constant current circuit and a second voltage which is a voltage of a drain of a second transistor that drives the light-emitting element to be the same voltage in a pre-light emission period before the light emission period.
Dependencies are inferred from the claim text.