AN W 2 (18 V, 8 Ω) Power Amplifier with Mute Function and Volume Control. ICs for Audio Common Use. Overview. Features.

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1 . W 2 (8 V, 8 Ω) Power Amplifier with Mute Function and Volume Control Overview The is a monolithic integrated circuit designed for. W (8 V, 8 Ω) output audio power amplifier. It is a dual channel SEPP IC suitable for stereo operation in TV application. Features Built-in DC volume control Built-in mute circuit Built-in thermal protection circuit Built-in over current protection circuit V CC operating range : 2.2 V to ±. 28.±. 2.±..2±. (.) (.).6 φ.6 R.8 7.7±. (2.5) (.2) 9.±. 2.9±. Unit : mm Applications TV HSIP2-P-A Volume Ripple filter Over current thermal protection circuit Mute In 2 Vol. N.C. In2 5 RF 6 2 Out2 7 NF2 8 GND 9 V CC NF Out (.27) (.27) (.) ±.5.8±.5.5±. 29.6±. Block Diagram

2 ICs for Audio Common Use Pin Descriptions Pin No. Description Mute control 2 Ch. input Volume control N.C. 5 Ch.2 input 6 Ripple filter Pin No. Description 7 Ch.2 output 8 Negative feedback ch.2 9 GND V CC Negative feedback ch. 2 Ch. output Absolute Maximum Ratings Parameter Symbol Rating Unit Supply voltage V CC V Supply current I CC.5 A Power dissipation *2 P D 7.5 W Operating ambient temperature * T opr 25 to +75 C Storage temperature * T stg 55 to +5 C Note) * : T a = 25 C except power dissipation, operating ambient temperature and storage temperature. *2 : Power dissipation of the package at T a = 75 C. Recommended Operating Range Parameter Symbol Range Unit Supply voltage V CC 2.2 to 27. Electrical Characteristics at V CC = 8 V, f = khz,, T a = 25 C Parameter Symbol Conditions Min Typ Max Unit Quiescent current I CQ No input signal 7 25 ma Voltage gain G V V IN = 9 mv 28 2 db Total harmonic distortion * THD V IN = 9 mv.. % Output power * P O THD = %.6. W Channel balance CB V IN = 9 mv db Max. volume attenuation * Att V IN = 9 mv 7 6 db Mute attenuation * M Att V IN = 9 mv 7 6 db Output noise voltage * V NO R g = kω, Din-Audio Filter.6. mv[rms] Note) * : With a filter band from 2 Hz to 2 khz used. 2

3 Application Circuit Example kω Audio mute Mute In 2. µf Vol. µf N.C. In2 5 µf kω RF 6 µf µf Out2 7 NF2 8 2 kω GND 9.7 µf µf 2 Ω kω V CC NF µf µf kω 8 V Out 2 2 kω.7 µf 2 Ω µf Usage Notes ) Depending on the maximum application output power, external heatsink may be needed. External heatsink should be fixed to the chassis. 2) Fin of the IC can be connected to GND. ) Please prevent output to V CC short and output to GND short. ) The temperature protection circuit will operate at T j around 5 C. However, if the temperature decreases, the protection circuit would automatically be deactivated and resume normal operation.

4 ICs for Audio Common Use Technical Information.Characteristic Curve Chart P O, THD V IN G V, THD f Output power P O (W). V CC = 8 V RL = 8 Ω f = khz Vol. = max. THD P O Total harmonic distortion THD (%) Voltage gain G V (db) V CC = 8 V RL = 8 Ω VIN = 9 mv Vol. = max. G V THD Total harmonic distortion THD (%).. k k k Input voltage V IN (mv) Frequency f (Hz) DC volume characteristics P O V CC Volume attenuation (db) 2 5 V CC = 8 V RL = 8 Ω VIN = 9 mv f = khz Output power P O (W) f = khz THD = % Vol. = max. RL = 6 Ω DC volume (V) Supply voltage V CC (V) P D T a Power dissipation P D (W) R th( j c) = 2 C/W R th( j a) = 2 C/W. No heat sink 2. C/W heat sink. 5 C/W heat sink. C/W heat sink 5. 2 C/W heat sink 6. C/W heat sink 7. Infinity heat sink Ambient temperature T a ( C)

5 Technical Information (continued) 2.Application Note ) Voltage gain The voltage gain of the can be varied by changing the resistor R2 as shown below : G VI Pin7,2 R is always fixed at 2 kω. R2 is variable. G V input= db which is fixed in internal circuit. Pin8 R G VO = 2 log (R /R 2 ) Typical values are : R = 2 kω, R 2 = kω C NF = µf G VO = 2 log (2 k/ k) R2 = 26 db G VTOTAL = G VI + G VO = db + 26 db = db 2) DC volume control The DC volume control range is V to. This range is used in order to be easily controlled by micro-computer using PWM output. The recommended circuit and volume attenuation characteristic are shown below : Volume attenuation Microcomputer IC Ω R 8 kω R5 2 kω PWM output Volume control C 2.2 µf Fig. Volume control interface circuit for.6 Volume at Pin 5 (V) Fig. Volume characteristic of ) Mute control Mute is ON when is applied to Pin. Then Q would turn ON and able to drive other part of the circuits. The external RC components provide a time constant for switching ON and OFF. Mute V OFF ON R kω Z MUTE C. µf 2 kω Q The purpose of the Mute is to attenuate the AC signal before it goes to the output. Threshold voltage at Pin : V.8 V 2. V Mute OFF Mute ON 5

6 ICs for Audio Common Use Technical Information (continued) 2.Application Note (continued) ) Oscillation To prevent oscillation, it is advisable to use RC (Zobel network) at output. C of polyester film capacitor has smaller characteristic fluctuation with temperature and frequency. The resistor R connected in series with C is effective for phase correction at high frequency, and as a result, it improves the oscillation allowance. Pin7 2 C R µf.7 µf 2 Ω 5) Power-ON/OFF pop-noise elimination The output pins 7, 2 and V O, during power turn ON and OFF are shown below : V CC RF 6 V CC V O Pin7 & Pin2 µf 7 µf C RF = µf C RF C VCC Turn ON time Turn OFF time The turn ON time in the is determined by the capacitance value of C RF. If value of the C RF is smaller, V O will turn ON faster. The turn OFF time is dependent on the capacitance value of C VCC. Pop-noise would occur when V CC voltage declines faster than RF voltage. To solve this, increase the discharge time of V CC by increasing the capacitance values of C VCC. The recommended values of capacitance for C VCC and C RF are shown below : No. C RF C VCC Recommended Operating V CC Range Unit µf 7 µf.5 to µf 7 µf 2.2 to 27. µf µf 2.2 to 27. 6

7 Technical Information (continued) 2.Application Note (continued) 6) Stand-by circuit Stand-by function can be implemented in the by external solution. It is realised by pulling the RF voltage to low and output voltage would follow RF as shown in the diagram. DC voltage ON Stand-by V OFF RF µf 6 /2V CC (Pin7 & Pin2) V O (DC) Stand-by Time 7