Available in a nine-bump WLP measuring 1 mm x 1 mm, the MAX98304 may be the industry’s smallest Class D amplifier available. Output power is 3.2W and its noise spec is 19 mVrms. The amplifier’s WLP features a no-connect middle bump, which allows the use of single-layer PCBs for lower manufacturing costs. Additionally, the use of patented EMI-reduction techniques enable what the company claims are the industry's lowest EMI emissions while eliminating the need for output filtering. Price starts at $0.42 each/1,000. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.