LMH6533

LMH6533 Four –Channel Laser Diode Driver with Dual Output, LVDS Interface and HFM Oscillator May 2004 LMH6533 Four –Channel Laser Diode Driver with Dual Output, LVDS Interface and HFM Oscillator General Description The LMH™ 6533 is a laser diode driver for use in combination DVD/CD recordable and rewritable systems. The part contains two high-current outputs for reading and writing the DVD (650 nm) and CD (780 nm) lasers. Functionality includes read, write and erase through four separate switched current channels. The channel currents are summed together at the selected output to generate multilevel waveforms for reading, writing and erasing of optical discs. The LVDS interface delivers DVD write speeds of 12x and higher while minimizing noise and crosstalk. The LMH6533 is optimized for both speed and power consumption to meet the demands of next generation systems. The part features a 150 mA read channel plus one 300 mA and two 150 mA write channels, which can be summed to allow a total output current of 500 mA or greater. The channel currents are set through four independent current inputs. The part is manufactured in National Semiconductor’s VIP10™ process, which features bonded wafer technology and trench isolation for very high switching speeds at low power levels. An on-board High-Frequency Modulator (HFM) oscillator helps reduce low-frequency noise of the laser and is enabled with the ENOSC pin. The fully differential oscillator circuit minimizes supply line noise, e...