Maxim's MAX98400A/MAX98400B class D amplifiers provide high-performance, thermally-efficient amplifier solutions
The MAX98400A/MAX98400B class D amplifiers provide high-performance, thermally-efficient amplifier solutions. The MAX98400A delivers 2 x 20 W into 8 Ω loads or 1 x 40 W into a 4 Ω load. The MAX98400B delivers 2 x 12 W into 8 Ω loads. An integrated limiting circuit prevents output-clipping distortion, protects small speakers from transient voltages, and reduces power dissipation. A thermal-foldback feature can be enabled to automatically reduce the output power at above a junction temperature of 120°C.
Traditional thermal protection is also available in addition to robust overcurrent protection. The ICs operate from a single 8 V to 28 V supply and provide a high 67 dB PSRR, eliminating the need for a regulated power-supply. They offer up to 90% efficiency from a 12 V supply. Filterless modulation allows the ICs to pass EN55022B EMI limits with 1 m cables using only a low-cost ferrite bead and small-value capacitor on each output. Both devices feature eight-digitally-controlled gain settings. Comprehensive click-and-pop reduction circuitry minimizes noise coming into and out of shutdown. The MAX98400A/MAX98400B are available in 36-pin and 24-pin TQFN packages, and are specified over the -40°C to 85°C temperature range.