120W MOSFET Power Amplifier with LM4702 Driver Chip explanation




National Semiconductor has been fast at work designing analog products for the high-end audiophile market. As for tune would have it, these products such as the LM4780 Power Amplifier Chip and the LM4702 Driver Chip are easy to implement into high-quality designs for the audio DIYer.
National recently introduced the LM4702, a high-voltage driver chip that interfaces bipolar or MOSFET output devices. The LM4702 provides two small signal, input stages and voltage amplifica tion stages (VAS). All you need to do is design a suitable bias system and output stage.
Not to be outdone in making the job easy for us amateurs, National provides a comprehensive design outline, guide to printed circuit board construction, ideas for the power supply, bill of materials, and suggested layout. In an application note dated May 20061, the company de scribed an amplifier using high-qual ity construction techniques and off-the-shelf passive components. The result is an amplifier with a vanishingly low level of distortion, 0.0006%. See More..