EL6835

® EL6835 www.DataSheet4U.com PRELIMINARY Data Sheet July 1, 2003 FN7231 Dual 4-Channel Driver with Oscillator & LVDS The EL6835 is a high performance, dual output, laser driver for writeable ‘super-combo’ CD - DVD drives. The ENA pin enables the chip, while the SEL1 pin selects the IOUT pin. Various waveforms can be generated where the amplitude is determined by the currents flowing into IINR, IIN2, IIN3, and IIN4. The timing is determined by the signals at WEN2-WEN2B, WEN3-WEN3B, and WEN4-WEN4B. The oscillator is enabled when OSEN is high. The amplified IINR current of the selected channel is enabled when the ENA pin is high. The total output current is the sum of the read current, the enabled write currents, and the oscillator current when enabled. Usually a voltage DAC will drive a resistor that is in series with the IINR, IIN2, IIN3, and IIN4 input. The resistor allows the user to optimize the current gain for each channel. Output write current pulses are enabled when a high is applied to the WEN2-WEN2B, WEN3-WEN3B, or WENWEN4B pin. The write current will flow to the selected output. When SEL1 is high IOUT1 is selected. WENRB enables read and oscillator current when low. The RF oscillators frequency is determined by RFREQ1 or RFREQ2, and its amplitude by RAMP1 or RAMP2. Features Two channels for CD or DVD Voltage-controlled output current source requiring one external set resistor per channel Rise time = 0.8ns Fall time = 0.8ns Channel 2 to 250mA max Ch...