RS Stock No. Product Details. Maximum Operating Temperature. Minimum Operating Temperature.
|Published (Last):||5 September 2018|
|PDF File Size:||5.22 Mb|
|ePub File Size:||9.14 Mb|
|Price:||Free* [*Free Regsitration Required]|
Dt Sheet. The built in muting function with turn on delay simplifies the remote operation avoiding switching on-off noises. Symbol Parameter Test Condition Min. On the P. Different values can be used; the following table can help the designer. Supply Voltage. Figure 4: Distortion vs. Output Power Figure 5: Output Power vs. Supply Voltage Figure 6: Distortion vs. Output Power Figure 7: Distortion vs.
Frequency Figure 8: Distortion vs. Frequency Figure Mute Attenuation vs. Vpin10 Figure St-by Attenuation vs. Vpin9 Figure Power Dissipation vs. Output Power Figure Power Dissipation vs. The task of realizing this linear integrated circuit in conventional bipolar technology is made extremely difficult by the occurence of 2nd breakdown phenomenon.
It limits the safe operating area SOA of the power devices, and as a consequence, the maximum attainable output power, especially in presence of highly reactive loads.
Moreover, full exploitation of the SOA translates into a substantial increase in circuit and layout complexity due to the need for sophisticated protection circuits. To overcome these substantial drawbacks, the use of power MOS devices, which are immune from secondary breakdown is highly desirable.
This large-signal, high-power buffer must be capable of handling extremely high current and voltage levels while maintaining acceptably low har- monic distortion and good behaviour over frequency response; moreover, an accurate control of quiescent current is required. A local linearizing feedback, provided by differential amplifier A, is used to fullfil the above requirements, allowing a simple and effective quiescent current setting.
Proper biasing of the power output transistors alone is however not enough to guarantee the absence of crossover distortion. While a linearization of the DC transfer characteristic of the stage is obtained, the dynamic behaviour of the system must be taken into account. Due to the absence of the 2nd breakdown phenomenon, the SOA of the power DMOS transistors is delimited only by a maximum dissipation curve dependent on the duration of the applied stimulus.
Full protection against electrostatic discharges on every pin is included. The circuits dedicated to the switching on and off of the amplifier have been carefully optimized to avoid any kind of uncontrolled audible transient at the output. The application of figure 17 shows the possibility of using only one command for both st-by and mute functions. On both the pins, the maximum applicable range corresponds to the operating supply voltage. These are both due to the low efficiency of conventional AB class amplifier approaches.
This allows the use of this device as a very high power amplifier up to W as peak power with T. Figure 20 shows the power dissipation versus output power curve for a class AB amplifier, compared with a high efficiency one. In order to dimension the heatsink and the power supply , a generally used average output power value is one tenth of the maximum output power at T.
From fig. To avoid that, in worst caseo conditions, the chip temperature exceedes C, the thermal resistance of the heatsink must be 0. As the above value is pratically unreachable; a high efficiency system is needed in those cases where the continuous RMS output power is higher than W.
The TDA was designed to work also in higher efficiency way. For this reason there are four power supply pins: two intended for the signal part and two for the power part. T1 and T2 are two power transistors that only operate when the output power reaches a certain threshold e. In figures 21,22 the performances of the system in terms of distortion and output power at various frequencies measured on PCB shown in fig.
We have 3 curves: total power dissipation, power dissipation of the TDA and power dissipation of the darlingtons. By considering again a maximum average output power music signal of 20W, in case of the high efficiency application, the thermal resistance value needed from the heatsink is 2.
Since the total power dissipation is less than that of a usual class AB amplifier, additional cost savings can be obtained while optimizing the power supply, even with a high headroom. Output Power Figure Distortion vs.
The characteristics shown by figures 27 and 28, measured with loads respectively 8 Ohm and 16 Ohm. In this application, the value of the load must not be lower than 8 Ohm for dissipation and current capability reasons. However, SGS-THOMSON Microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use.
Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. Open as PDF.
Add to Favourites. Finally, we would like you to leave your contact email so that we can update you on our process. View Favourites Continue Shopping. Recommended For You.
Something went wrong...
TDA7294V - TDA7294 100V 100W DMOS Audio Amplifier