Indicator circuit and apparatus using the same
AssigneeInterDigital CE Patent Holdings, SAS
InventorsZhijun Liao, Chao Zeng, Ren Zhang
Life of this patent
Estimating the term…
Abstract
An indicator circuit (10) includes a first light emission device (R1 and D1) configured to be driven by a first voltage (Von) to emit light; a second light emission device (R2 and D2) configured to be driven by a second voltage (Vstb) to emit light; and a control device (Q1, D3 and R3) configured to be driven by the first voltage (Von) and the second voltage (Vstb) to allow the first light emission device (R1 and D1) to be driven when the first voltage (Von) is active but the second voltage (Vstb) is not active and not to allow the first light emission device (R1 and D1) to be driven when the first voltage (Von) and the second voltage (Vstb) are active.
Claims8
An indicator circuit comprising:
- a first light emission device configured to be driven by a first voltage to emit light;
- a second light emission device configured to be driven by a second voltage to emit light;
- and
- a control device configured to be driven by the first voltage and the second voltage to allow the first light emission device to be driven when the first voltage is active but the second voltage is not active and not to allow the first light emission device to be driven when the first voltage and the second voltage are active,
- wherein the control device is configured to allow a current to flow from a terminal to which the second voltage is applied to the first light emission device but prevent a current from flowing out from the first light emission device when the first voltage and the second voltage are active, and
- wherein the control device is configured to allow a current coming from a terminal to which the first voltage is applied to flow through and out from the first light emission device when the first voltage is active but the second voltage is not active.
A method of driving a first light emission device driven by a first voltage and a second light emission device driven by a second voltage, comprising:
- allowing the first light emission device to be driven to emit light when the first voltage is active but the second voltage is not active;
- not allowing the first light emission device to be driven when the first voltage and the second voltage are active,
- allowing a current to flow from a terminal to which the second voltage is applied to the first light emission device but prevent a current from flowing out from the first light emission device when the first voltage and the second voltage are active, and
- allowing a current coming from a terminal to which the first voltage is applied to flow through and out from the first light emission device when the first voltage is active but the second voltage is not active.
Dependencies are inferred from the claim text.