AN5272

AN5272 PANASONIC

Document overview

• Manufacturer or author: Provided By digicamel.com
• PDF pages: 6

Technical content

4.0 W · 2 (18 V, 8 W ) Power Amplifier with

Variable Audio Output and Volume Control n Overview The AN5272 is a monolithic integrated circuit designed for 4.0 W (18 V, 8 W ) output audio power amplifier. It is a dual channel SEPP IC suitable for stereo operation in TV application. n Features

• Built-in DC volume control
• Built-in thermal protection circuit
• Built-in over current protection circuit
• 2 Variable Audio Output (VAO)
• V CC operating range : 12.2 V to 27.5 V n Applications
• TV HSIP012-P-0000A Unit : mm VAO 1 1 In1 2 V ol.3 VAO 2 4 In2 5 RF 6 Out2 7 NF2 8 GND 9 V CC NF1 11 Out1 12 V olume Ripple filter Over current thermal protection circuit 7.7–0.3 (12.5) 19.1–0.3 21.9–0.3 (1.2) (10.0)(10.0) 29.6–0.3 20.0–0.3 0.6 28.0–0.3 29.75–0.30 f3.6 R1.8 121 +0.15 –0.052.540.25 1.45–0.151.80–0.15 1.2–0.1 3.5–0.3 +0.10 –0.05 n Block Diagram

AN5272 ICs for Audio Common Use n Electrical Characteristics at VCC = 18 V, f = 1 kHz, RL = 8 W , Ta = 25 °C n Absolute Maximum Ratings Parameter Symbol Rating Unit Supply voltage V CC 30 V Supply current I CC 3.5 A Power dissipation *2 PD 37.5 W Operating ambient temperature *1 Topr -25 to +75 °C Storage temperature *1 Tstg -55 to +150 °C n Recommended Operating Range Parameter Symbol Range Unit Supply voltage V CC 12.2 to 27.5 V Note) *1 :T a = 25 °C except power dissipation, operating ambient temperature and storage temperature. *2 : Power dissipation of the package at Ta = 75 °C. Parameter Symbol Conditions Min Typ Max Unit Quiescent current I CQ No input signal 17 25 33 mA Voltage gain G V V IN = 90 mV 28 30 32 dB Total harmonic distortion *1 THD V IN = 90 mV 0.3 1.0 % Output power *1 PO THD = 10 % 3.6 4.1 W Channel balance CB V IN = 90 mV -10 1d B Max. volume attenuation *1 Att V IN = 90 mV -70 -64 dB VAO voltage gain G VAO V IN = 90 mV 10 12 14 dB Output noise voltage *1 V NO R g = 10 kW , Din-Audio Filter 0.6 1.0 mV[rms] Note) *1 : With a filter band from 20 Hz to 20 kHz used. Pin No. Description 7 Ch.2 output 8 Negative feedback ch.2

9 GND

10 V CC

11 Negative feedback ch.1 12 Ch.1 output Pin No. Description

1 Variable audio output 1

2 Ch.1 input

3 Volume control

4 Variable audio output 2

5 Ch.2 input

6 Ripple filter

ICs for Audio Common Use AN5272 n Application Circuit Example V AO1 1 In1 2 V ol. 3 V AO2 4 In2 5 RF 6 Out2 7 NF2 8 GND 9 V CC 10 NF1 11 Out1 12 AN5272 1 mF 1 mF 0.047 mF 10 mF R L = 8 W R L = 8 W

18 VVariable audio

20 W 1 kW

0.047 mF 10 mF

20 W1 kW

1) 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. 3) Please prevent output to VCC short and output to GND short. 4) The temperature protection circuit will operate at Tj around 150 °C. However, if the temperature decreases, the protection circuit would automatically be deactivated and resume normal operation.

AN5272 ICs for Audio Common Use n Technical Information 1.Characteristic Curve Chart PO , THD ¾ VIN G V , THD ¾ f G VAO ¾ fP O ¾ VCC DC volume characteristics P D ¾ Ta Output power PO (W) Total harmonic distortion THD (%) 0.01 0.1 0.1 100 1000100101 Input voltage VIN (mV) V CC = 18 V R L = 8 W f = 1 kHz V ol. = max. PO THD Voltage gain GV (dB) 100k10k1k10 100 Frequency f (Hz) G V V CC = 18 V R L = 8 W V IN = 90 mV V ol. = max.22 0.2 0.4 0.6 0.8 1.0 Total harmonic distortion THD (%) THD Voltage gain GVAO (dB) 100k10k1k10 100 Frequency (Hz) V CC = 18 V R L = 8 W V IN = 90 mV V ol. = max.

12 G V

Supply voltage VCC (V) Output power PO (W) 14 16 18 20 22 24 26 f = 1 kHz THD = 10 % V ol. = max. R L = 8 W R L = 16 W -70 -60 -50 -40 -30 -20 -10 DC volume (V) Volume attenuation (dB) 4321 V CC = 18 V R L = 8 W V IN = 90 mV f = 1 kHz 0 25 150 पғԹ౓ Ta (°C) ࣦPD (W) 3.0 10.4 17.9 31.3 41.7 62.5 50 75 100 125 R th( j-c) = 2 °C/W R th( j-a) = 42 °C/W 1. No heat sink 2. 10 °C/W heat sink 3. 5 °C/W heat sink 4. 3 °C/W heat sink 5. 2 °C/W heat sink 6. 1 °C/W heat sink 7. Infinity heat sink

ICs for Audio Common Use AN5272 n Technical Information (continued) 2.Application Note 1) Voltage gain The voltage gain of the AN5272 can be varied by changing the resistor R2 as shown below : R1 is always fixed at 20 kW . R2 is variable. G VO = 20 log (R1/R2) Typical values are : R1 = 20 kW , R2 = 1 kW G VO = 20 log (20 k/1 k) = 26 dB G VTOTAL = GVI + GVO = 4 dB + 26 dB = 30 dB 2) DC volume control The DC volume control range is 0 V to 5 V. 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 : 3) 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. 12 kW 2.2 mF PWM output Microcomputer IC 18 kW Fig. V olume control interface circuit for AN5272 300 W AN5272 V olume control Fig. V olume characteristic of AN5272 V olume attenuation 0 0.6 V olume at Pin35 (V) Pin8 Pin7,12 C NF = 10 mF G V input = 4 dB which is fixed in internal circuit. G VI 0.047 mF R L = 8 W20 W C Pin7 R 1000 mF

AN5272 ICs for Audio Common Use n Technical Information (continued) 2.Application Note (continued) 4) Power-ON/OFF pop-noise elimination The output pins 7, 12 and VO , during power turn ON and OFF are shown below : The turn ON time in the AN5272 is determined by the capacitance value of CRF . If value of the CRF is smaller, VO would turn ON faster. The turn OFF time is dependent on the capacitance value of CVCC . Pop-noise would occur when VCC voltage declines faster than RF voltage. To solve this, increase the discharge time of VCC by increasing the capacitance values of CVCC . The recommended values of capacitance for CVCC and CRF are shown below : No. C RF C VCC Recommended Operating VCC Range Unit 1 33 mF 470 mF 14.5 to 27.5 V 2 47 mF 470 mF 12.2 to 27.5 V 3 100 mF 1000 mF 12.2 to 27.5 V 5) Stand-by circuit Stand-by function can be implemented in the AN5272 by external solution. It is realised by pulling the RF voltage to low and output voltage would follow RF as shown in the diagram. RF 6 V CC 10 C VCCC RF V CC V O Pin7 Pin12 Turn ON time Turn OFF time C RF = 100 mF 33 mF 47 mF RF 1/2VCC 5 V 100 mFON OFF 5 V 5 V 0 V Stand-by DC voltage (Pin7 & Pin12) Time Stand-by V O (DC)