The T0815 is a laser diode driver for the operation of a grounded laser diode for CDRW drives. It includes three channels for three different optical power levels which are controlled by a separate IC. The read channel generates a continuous output level whereas the channels 2 and 3 are provided as write channels with very fast switching speeds. Write current pulses are enabled when a `low' signal is applied to the NE pins. All channels are summed together at the IOUT pin. Each channel can contribute up to 250 mA to the total output current of up to 300 mA. A total gain of 400 is provided between each reference current input and the output. Although the reference inputs are current inputs; voltage control is possible by using external resistors. An on-chip RF oscillator is provided to reduce laser mode hopping noise during read mode. Frequency and swing can be set by two external resistors. Oscillation is enabled by a `high' at the ENOSC pin. Complete output current and oscillator switchoff is achieved by a `low' at the ENABLE input. The T0815 also includes a fast settling APC (Adaptive Power Control) transimpedance amplifier. It is provided to interface between the front end monitor photo diode and the ALPC (Adaptive Laser Diode Power Controller) circuit.