ATR0881£ºAtmel Unveils Industry's Smallest Laser Diode Driver Solution Supporting HD-DVD/Blu-ray, DVD and CD Format

The ATR0881's QFN housing is a lead-free paddle-up package with the exposed paddle on top to improve heat dissipation. A bottom-located exposed paddle, as found in conventional QFN packages, causes difficulties due to its inaccessibility for circuit design, particularly in optical pick-up products. This design restriction is eliminated with Atmel¡¯s ATR0881.

Although the ATR0881 has 3 outputs for connecting 3 laser diodes ¨C a blue (HD-DVD/Blu-ray), a red (DVD), and an infrared (CD) ¨C it still fits into the same small 24-pin package used by Atmel¡¯s well-known laser diode drivers for two-output combined DVD and CD drives.

The ATR0881 is the first of its kind with a serial interface. Whereas conventional laser diode drivers have a fixed gain between input and output, the gain of each of the ATR0881's 5 channels can be individually programmed using the serial interface. As a result, the ATR0881 is extremely flexible and avoids complete re-designs if the users¡¯ gain requirements change.

The serial interface can also be used to set all parameters of the integrated oscillator including frequency, amplitude, and spread-spectrum settings. Current laser diode drivers need up to 6 external resistors and pins to set the oscillator parameters. With the ATR0881, these additional resistors are not required; thus the overall bill of material is reduced.

The requirement for oscillator frequency accuracy is very high to ensure low electromagnetic interference. Due to resistor tolerances, common laser diode drivers enable a maximum accuracy of ¡À 10%. In contrast, designs using the ATR0881 achieve a frequency deviation of less than ¡À5% thanks to the laser diode driver's integrated frequency counter.

Compared to competitor devices, the ATR0881 can optionally be set to a special synchronization mode, which synchronizes all write channels to the second channel, thus enabling the generation of very sharp output pulses for increased data security.

Availability and Pricing

Samples of the ATR0881 in 4 mm x 4 mm QFN24 paddle-up packages are now available.

DVD = Digital Versatile Disc

HD = High Density

LDD = Laser Diode Drivers

QFN = Quad Flat No Leads