This user manual describes More information. Basic information on how to choose a suitable MOSFET device, setting bias levels, performance optimizations, and performance results will be covered. A simple bias resistor circuit will give stable bias current over operating temperature. The C N capacitor shunts high frequency noise present at the input to ground. Supply bypassing and PCB design each have a significant effect on harmonic distortion levels. The MOSEFET devices listed in Table 1 below are devices from three suppliers that will meet the design criteria based on the LM limitations for direct drive and the target output power specification into a resistive load.

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This point occurs when the slew rate limit is reached. Can the model OPAxyz be operated. The effects of bias instability on sonic performance is not investigated in this application note.

High End W MOSFET IC Driven Amp | audioXpress

The values are determined by trial and error adjustment for each set of devices. It consists of audik independent, high gain, internally compensated, low power operational amplifiers which have been designed to More information.

Minimum number of external parts required No input capacitor, bootstrap. Output Power graphs show the performance over the frequency and power range of interest. With high unity gain frequency and a guaranteed More information.


The apparent difference in the plots for the direct drive channel to the previous direct drive W Frequency Response graph above is that the output power is only 60W. See questions and answers. The output stage is shown in Figure LM Audio Power Amplifier General Description The LM is a power audio amplifier for consumer application In order to hold system cost to a minimum gain is internally fixed at 34 db A unique input.

Slew rate can be increased using an intermediate driver or buffer stage. The time steps are one reason for the different slopes on the time curve, more evident on the higher bias graphs.

An additional film capacitor used in parallel may improve the sonic quality. This voltage More information. Modern day electronics are often battery powered, forcing the.

The pole location created by the circuit is found using Equation 4 below. One of the most common Op Amps available. The graph is created the same as done for the other devices.

The bias voltage is measured with mA of bias current at initial power on when the case temperature of the devices is low. As can be easily seen, the channel with the driver stage has much higher bandwidth because of higher slew rate. V GS is used to determine if correct bias can be achieved with 3V or less.


LM4702 Assembly 2X100W Class AB Audio Power Amplifier Board ± 45V – ± 60V

Higher bias current reduces harmonic distortion levels. All overload protection circuitry remains fully functional. Use a heat sink for the LM The compensation audip, C C, sets the slew rate and phase margin to ensure oscillation-free operation.

Kristen Gunia Prepared More information. There was a problem completing your request.

Optimizations in the driver stage may result in better performance. Typically it provides 22W output power.

It may be desirable to have higher bias current to reduce distortion harmonics, improve THD performance, affect sonic qualities, or some other design criteria. General-purpose single operational amplifier.

The LM, with feedback from the output stage, sets the gain and is externally compensated to lm44702 the slew rate. Which amplifier topology is better for my application, current feedback or voltage feedback?