The SL6028 is a high performance dual four-channel laser driver that provides controlled current to two grounded laser diodes. 

The SEL1 pin selects IOUT1 or IOUT2 pin active to drive either CD or DVD laser diode.

The currents flowing into  IINR, IIN2, IIN3 and IIN4 determine the level  of the  output current.

The channel enable pin at WENRB, or the pin pairs of WEN2-WEN2B, WEN3-WEN3B, and WEN4WEN4B determine current waveform timing. The  output write  current pulses are enabled when a low is applied to WENRB or high-low to  these  pin pairs with switching speed less than 1 ns rise/fall time.

Two on-chip oscillators can provide  up to 600MHzmodulation to the output current. Pin pair OSENOSENB is held high-low to turn on the oscillators.Each oscillator’s amplitude and  frequency  is set by an external resistor connected to ground from RAMP1 or RAMP2. And frequency is set from RFREQ1 or RFREQ2.

The total output current is the sum of current from the four charnels and the oscillator. The channel enables are LVDS interface. IOUT1or IOUT2 is enabled by when SEL1 is high or low respectively. 

There is a whole chip enable pin ENA needed to be high. And complete LD shut-off is achieved by holding ENA low.

The SL6028 is available in 32-pin 5x6 mm QFN package.