IrDA transceiver module that also functions as remote control IR transmitter
First Claim
1. A method, comprising:
- providing an inductor in a current path through which an LED drive current flows through a light emitting diode (LED) of an IrDA transceiver module, wherein the LED emits infrared light whose intensity peaks at a wavelength below 900 nm.
5 Assignments
0 Petitions
Accused Products
Abstract
The infrared LED of an IrDA module transmits IR energy with a peak wavelength (for example, 875 nm) appropriate for IrDA communication. This peak wavelength is lower than is the wavelength (for example, 940 nm) used in ordinary IR remote controls (RC). The IrDA LED does, however, transmit some energy at the wavelength of the peak sensitivity of an RC receiver. When making an IrDA transmission, the IrDA LED is driven with a lower amount of current. When making an RC transmission, the IrDA LED is driven with an increased amount of current such that higher wavelength emissions received by the RC receiver are of adequate power to realize RC communication. A passive circuit is disclosed for automatically increasing IrDA LED current during RC transmissions. The circuit involves an inductor that shunts current around a current-limiting resistor used to limit LED drive current.
31 Citations
20 Claims
-
1. A method, comprising:
providing an inductor in a current path through which an LED drive current flows through a light emitting diode (LED) of an IrDA transceiver module, wherein the LED emits infrared light whose intensity peaks at a wavelength below 900 nm. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
11. A circuit, comprising:
-
an IrDA transceiver module having a light emitting diode (LED), wherein the LED emits infrared light whose intensity peaks at a wavelength below 900 nm; and an inductor in a current path through which an LED drive current flows through the LED, wherein the LED is adapted to transmit both an IrDA transmission and a remote control (RC) transmission. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification