Datasheet TDA7056B (NXP) - 4

NXP Semiconductors Product specification 5 W mono BTL audio amplifier with DC TDA7056B volume control
FUNCTIONAL DESCRIPTION
The maximum gain of the amplifier is fixed at 40.5 dB. The DC volume control stage has a logarithmic control The TDA7056B is a mono BTL output amplifier with DC characteristic. Therefore, the total gain can be controlled volume control, designed for use in TV and monitor but is from 40.5 dB to 33 dB. If the DC volume control voltage also suitable for battery-fed portable recorders and radios. falls below 0.4 V, the device will switch to the mute mode. In conventional DC volume circuits the control or input The amplifier is short-circuit proof to ground, V stage is AC coupled to the output stage via external P and across the load. Also a thermal protection circuit is capacitors to keep the offset voltage low. In the TDA7056B implemented. If the crystal temperature rises above the DC volume control stage is integrated into the input +150 C the gain will be reduced, thereby reducing the stage so that no coupling capacitors are required. With this output power. Special attention is given to switch-on and configuration, a low offset voltage is still maintained and switch-off clicks, low HF radiation and a good overall the minimum supply voltage remains low. stability. The BTL principle offers the following advantages: Lower peak value of the supply current
Power dissipation
The frequency of the ripple on the supply voltage is twice Assume VP = 12 V; RL = 16 . the signal frequency. The maximum sine wave dissipation is = 1.8 W. Consequently, a reduced power supply with smaller The Rth vj-a of the package is 55 K/W. capacitors can be used which results in cost reductions. Therefore Tamb (max) = 150  55  1.8 = 51 C. For portable applications there is a trend to decrease the supply voltage, resulting in a reduction of output power at conventional output stages. Using the BTL principle increases the output power.
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT
VP supply voltage  18 V V3, 5 input voltage pins 3 and 5  5 V IORM repetitive peak output current  1.25 A IOSM non-repetitive peak output current  1.5 A P  tot total power dissipation Tcase 60 C  9 W Tamb operating ambient temperature 40 +85 C Tstg storage temperature 55 +150 C Tvj virtual junction temperature  +150 C Tsc short-circuit time  1 h
THERMAL CHARACTERISTICS SYMBOL PARAMETER VALUE UNIT
Rth j-a thermal resistance from junction to ambient in free air 55 K/W Rth j-c thermal resistance from junction to case 10 K/W 1997 Aug 15 4 Document Outline Features General description Quick reference data Ordering information Block diagram Pinning Functional description Power dissipation Limiting values Thermal characteristics Characteristics Test and application information Package outline Soldering Introduction Soldering by dipping or by wave Repairing soldered joints Data sheet status Definitions Disclaimers