Abstract:
A hybrid LDD includes a read channel to selectively output a read current, a plurality of write channels, each to selectively output a different write current, and an oscillator channel to selectively output an oscillator current. Additionally, the hybrid LDD includes programmable LDD controller that receives the plurality of enable signals from the external controller, and based on the enable signals, controls timing of the currents output by at least the write channels. The programmable LDD controller can also control timing of the currents output by the read and oscillator channels, based on the enable signals. Further and alternative embodiments are also provided.
Abstract:
Double buffering of serial transfers is provided in order to allow for increased serial transfer rate without requiring increased internal processing speeds. A laser driver serial controller serially receives a word including address bits and data bits. During a write operation, the address bits are serially shifted into an address shift register of the laser driver, and the data bits are serially shifted into a data shift register of the laser driver. After the address bits and data bits are completely shifted into the respective address and data shift registers, the address bits and data bits are transferred in parallel to address and data holding registers of the laser driver. After the parallel transfers of the address bits and data bits from the address and data shift registers to the address and data holding registers, the address and data shift registers are available to serially receive additional address bits and data bits of an additional word.
Abstract:
A hybrid LDD includes a read channel to selectively output a read current, a plurality of write channels, each to selectively output a different write current, and an oscillator channel to selectively output an oscillator current. Additionally, the hybrid LDD includes programmable LDD controller that receives the plurality of enable signals from the external controller, and based on the enable signals, controls timing of the currents output by at least the write channels. The programmable LDD controller can also control timing of the currents output by the read and oscillator channels, based on the enable signals. Further and alternative embodiments are also provided.
Abstract:
Double buffering of serial transfers is provided in order to allow for increased serial transfer rate without requiring increased internal processing speeds. A laser driver serial controller serially receives a word including address bits and data bits. During a write operation, the address bits are serially shifted into an address shift register of the laser driver, and the data bits are serially shifted into a data shift register of the laser driver. After the address bits and data bits are completely shifted into the respective address and data shift registers, the address bits and data bits are transferred in parallel to address and data holding registers of the laser driver. After the parallel transfers of the address bits and data bits from the address and data shift registers to the address and data holding registers, the address and data shift registers are available to serially receive additional address bits and data bits of an additional word.
Abstract:
Methods and system are provided for automatic power control of a laser diode, e.g., in a laser driver. In accordance with an embodiment of the present invention, a power controller includes a detector circuit adapted to detect the output of the laser diode and to produce a measured output therefrom. A comparator compares a desired output to the measured output, and produces an error signal therefrom. The error signal is provided to an integrator circuit that produces an integrated error signal. At least one digital-to-analog converter (DAC) uses the integrated error signal to produce a current drive signal that drives the laser diode.
Abstract:
Methods and system are provided for automatic power control of a laser diode, e.g., in a laser driver. In accordance with an embodiment of the present invention, a power controller includes a detector circuit adapted to detect the output of the laser diode and to produce a measured output therefrom. A comparator compares a desired output to the measured output, and produces an error signal therefrom. The error signal is provided to an integrator circuit that produces an integrated error signal. At least one digital-to-analog converter (DAC) uses the integrated error signal to produce a current drive signal that drives the laser diode.
Abstract:
Methods and systems for allowing multiple devices to share the same serial lines (e.g., SDIO, SEN and SCLK) are provided. Such devices can be located, e.g., on an optical pick-up unit. Each device includes a serial interface, a device enable number (DEN) that differs from the DEN of each other device, and a plurality of registers, with at least one register being designated a device select register (DSR). The DSRs of the plurality of devices share a common address. The plurality of serial interfaces are collectively enabled and collectively disabled (e.g., via the SEN line). However, only one of the plurality of serial interfaces can be selected at one time, with the remaining of the plurality of serial interfaces being deselected. The serial interface of a device is selected when the DEN of the device is the same as the content of the DSR of the device, and deselected when the DEN of the device is not the same as the content of the DSR of the device.
Abstract:
Double buffering of serial transfers is provided in order to allow for increased serial transfer rate without requiring increased internal processing speeds. A serial controller serially receives a word including address bits and data bits. During a write operation, the address bits are serially shifted into an address shift register, and the data bits are serially shifted into a data shift register. After the address bits and data bits are completely shifted into the respective address and data shift registers, the address bits and data bits are transferred in parallel to address and data holding registers. After the parallel transfers of the address bits and data bits from the address and data shift registers to the address and data holding registers, the address and data shift registers are available to serially receive additional address bits and data bits of an additional word.
Abstract:
Systems, methods and devices provide for fast and power efficient transfer of three color data words (e.g., a M-bit red color word, a M bit green color word and a M-bit blue color word) per pixel from a controller to a laser diode driver (LDD). First and second transfer words are produced based on the three color data words. The first transfer word is transferred from the controller to the LDD and stored at LDD in response to a low-to-high portion of a cycle of a data transfer clock, and the second transfer word is transferred and stored in response to a high-to-low portion of a cycle of the data transfer clock. The first, second and third color data words are reproduced by the LDD in dependence on the first and second received transfer words. First, second and third DACs of the LDD are driven with the first color data word, the second color data word, and the third color data word. Three light sources (e.g., red, green and blue laser diodes or LEDs) are driven with output currents of the DACs.
Abstract:
Systems, methods and devices provide for fast and power efficient transfer of three color data words (e.g., a M-bit red color word, a M bit green color word and a M-bit blue color word) per pixel from a controller to a laser diode driver (LDD). First and second transfer words are produced based on the three color data words. The first transfer word is transferred from the controller to the LDD and stored at LDD in response to a low-to-high portion of a cycle of a data transfer clock, and the second transfer word is transferred and stored in response to a high-to-low portion of a cycle of the data transfer clock. The first, second and third color data words are reproduced by the LDD in dependence on the first and second received transfer words. First, second and third DACs of the LDD are driven with the first color data word, the second color data word, and the third color data word. Three light sources (e.g., red, green and blue laser diodes or LEDs) are driven with output currents of the DACs.