LA41822.Proper cares in using IC . If the IC is used in the vicinity of the maximum rating, even a slight variation in conditions may cause the maximum rating to be exceeded, thereby leading to a breakdown. Allow an ample margin of variation for supply voltage, etc. and use the IC in the range where the maximum rating is not exceeded. Pin-to-pin short If the supply voltage is applied when the space between pins is shorted, a breakdown or deterioration may occur. When mounting the IC on the board of applying the supply voltage, make sure that the space between pins is not shorted with solder, etc. Load short If the IC is used with the load shorted for a long time, a breakdown or deterioration may occur. Be sure not to short the load. When the IC is used in radios or radio-cassette tape recorders, keep a good distance between IC and bar antenna. When making the board, refer to the example of printed circuit pattern. Proper cares in operating a set with LA4182 incorporated When a set with the LA4182 incorporated is operated from AC power supply, a momentary drop in supply voltage is caused by the transformer regulation, etc. at the time of turning ON the motor with the circuit shown below. In this case, if ripple noise is generated from the speaker or headphone, take the following actions. 1. Connect a diode (rectifier diode of average rectified current IO = 100 to 200 mA) across pins 6 and 12 of the LA4182 so that the voltage at pin 6 can follow the supply voltage regulation. In the steady state, this diode is cut off. 2. Increase the capacity of the power source capacitor so that the supply voltage regulation can be minimized. Unit (capacitance: F) Radiation design . Since the DIP 12-pin package is so designed as to be able to radiate heat through the Cu-foiled area of printed circuit board under normal operating conditions, make the Cu-foilled area near the fin of IC as large as possible when designing the printed circuit board. By providing the Cu-foiled area covered by the broken line as shown in the above-mentioned example of printed circuit pattern, a rather satisfactory radiation is enabled. (Refer to the Pd max-Ta characteristics.) . Since the power dissipation (Pd) goes higher depending on the conditions of supply voltage and load, it is recommended to use a fin together with the printed circuit board. The following equations are rule-of-thumb guides for Pd (for stereo). For AC power supply, it is desirable to measure with the transformer of each individual set. In the bridge amplifier application, calculation should be made with 1/2 of the load used. (1) DC power supply V 2 CC Pd max = + I v V π2 CCO CC (For stereo) RL No.742-5/10