The PT5321 is a dual bridge-connected audio power amplifier which, when connected to a 5V supply, will deliver 2.1W to a 4Ω load or 2.4W to a 3Ω load with less than 1.0% THD+N. In addition, the headphone input pin allows the amplifiers to operate in single-ended mode when driving stereo headphones.
The PT5321 has two separate HP (headphone) enable inputs, each having different logic level thresholds. Either HP enable input activates the single ended headphone mode and disables the BTL output mode. The HP Sense input is for use with a normal stereo headphone jack. The remaining input, HP Logic, accepts standard logic level thresholds. The PT5321 provides a user selectable “3D Enhancement” mode to enhance stereo imaging.
The PT5321 features a low-power consumption shutdown mode and thermal shutdown protection. It also utilizes circuitry to reduce “pop and click” during device turn-on.
¨ PO@1% THD+N:
¨ 3Ω, 4Ω loads: 2.5W (typ), 2.2W (typ)
¨ 8Ω load: 1.1W (typ)
¨ SE mode THD+N@75mW into 32Ω: 0.01% (max)
¨ Shutdown current: 0.7µA (typ)
¨ Supply voltage range: 2.5V to 5.5V
¨ PSRR@217Hz: 85dB (typ)
¨ Selectable headphone enable modes
¨ 3D Enhancement
¨ Stereo headphone amplifier mode
¨ “Click and pop” suppression circuitry
¨ Unity-gain stable
¨ Thermal shutdown protection circuitry
¨ PCB area-saving QFN-24 package
¨ Cell phones
¨ Multimedia monitors
¨ Portable and desktop computers
¨ Portable audio systems