Description
The TPA0252 is a stereo audio power amplifier in a 24-pin TSSOP thermally enhanced package capable of delivering 2.8 W of continuous RMS power per channel into 3-O speakers, the TPA0252 has less than 0.3% THD+N across its specified frequency range. The integrated depop circuitry virtually eliminates transients that cause noise in the speakers. Amplifier gain is controlled by two terminals, UP and DOWN. There are 31 discrete steps covering the range of 20 dB (maximum volume setting) to –40 dB (minimum volume setting) in 2 dB steps. By pressing either button momentarily, the volume steps up or down 2 dB. By continuing to hold the button down, the device starts stepping through volume settings at a rate determined by the capacitor on the CLK terminal. An internal input MUX, controlled by the HP/LINE pin, allows two sets of stereo inputs to the amplifier. In notebook applications, where internal speakers are driven as BTL and the line outputs (often headphone drive) are required to be SE, the TPA0252 automatically switches into SE mode when the SE/BTL input is activated. This effectively reduces the gain by 6 dB. The TPA0252 includes a VAUX terminal that is used to power the volume-setting registers when the device is in SHUTDOWN, and even if the main VDD power supply is removed. As long as the VAUX terminal is held above 3 V, the registers are maintained. If the VAUX terminal is allowed to go below 3 V, then the data in the registers is lost, and the default gain of –10 dB is loaded into the registers. The TPA0252 consumes only 9 mA of supply current during normal operation. A miserly shutdown mode reduces the supply current to less than 150 µA. The PowerPAD package (PWP) delivers a level of thermal performance that was previously achievable only in TO-220-type packages. Thermal impedances of approximately 35°C/W are truly realized in multilayer PCB applications. This allows the TPA0252 to operate at full power into 😯 loads at ambient temperatures of 85°C.
