AD9561

The AD9561 is a second generation high speed, digitally programmable pulse width modulator (PWM). Output pulse width is proportional to an 8-bit DATA input value. Two additional control inputs determine if the pulse is placed at the beginning, middle or end of the clock period. Pulse width and placement can be changed every clock cycle up to 60 MHz.

Pulse width modulation is a well proven method for controlling gray scale and resolution enhancement in scanning laser print engines. Modulating pulse width provides the most cost effective method for continuous tone reproduction and resolution enhancement in low-to-moderate cost scanning electro-photographic systems.

The AD9561 uses precision analog circuits to control dot size so that near-photographic quality images are practical without the high frequency clock signals required by all digital approaches.

The AD9561 has improved features and performance over its predecessor, the AD9560. An improved ramp topology enables control of pulse width through 100% of the dot clock period as opposed to 95% for the AD9560. This enables smooth transition across dot boundaries for line screen applications.