The EL6205 consists of a variable
amplitude, push only, oscillator that
also supplies the laser DC current. It is
designed to easily interface to existing ROM controllers,
reducing parts count, and power dissipation.
The reduction of parts count and the small package allows
the oscillator to be placed closer to the laser, thus reducing
EMI. Also, the turn-on and turn-off edges are slew rate
limited to reduce higher harmonics.
The total current drawn from the power supply can be less
than the laser threshold current due to the unique push-only
modulation method. The average current is less than the
peak oscillator current, and can be less than half of the
oscillator current. The power control current supplied from
the main board is reduced to less than 2mA.
One external resistor sets the oscillator frequency. A current
applied to the IIN terminal determines the amplitude of the
oscillator and laser DC current. If the oscillator amplitude is
set very low, the output and oscillator are disabled. The part
is available in the space-saving 6-pin SOT-23 package. It is
specified for operation from 0°C to +70°C.