SA7265 2-CH AUDIO POWER AMPLIFIER(25W X2) DESCRIPTION The SA7265 is a monolithic integrated circuit in HSIP package, intended for use as dual audio frequency class AB amplifier. FEATURES HSIP-11 * Wide supply voltage range up to 50V ABS MAX. * Split supply operation. * High output power: 25 + 25W @ THD=10%,RL=8Ω,Vs=±20V * Mute/stand-by function. HSIP-15 * Few external components. * Short circuit protection. * Thermal overload protection. APPLICATIONS ORDERING INFORMATION * Hi-Fi music centers Part No. Package * Stereo TV sets SA7265 HSIP-11 SA7265A HSIP-15 BLOCK DIAGRAM Note: Figures for the SA7265. HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 1 of 12 SA7265 ABSOLUTE MAXIMUM RATING Characteristics Symbol Rating Unit Vs 50 or ±25 V Io 4.5 A Ptot 30 W Tstg, Tj -40~+150 °C Vs(sc) ±18(*) V Rth(j-c) 2 °C/W DC Supply Voltage Output Peak Current (Internally Limited) Power Dissipation Tcase=70°C Storage And Junction Temperature Supply Voltage to Guarantee Shortcircuit Protection Thermal Resistance From Junction To Case (Max) (*)Maximum supply voltage to guarantee short-circuit to ±Vs is ±18V, and to GND short-circuit protection is normal. ELECTRICAL CHARACTERISTICS (Refer to the test circuit, Vs±20V; RL=8Ω; Rs=50Ω; Gv=30dB; f=1KHz; Tamb=25°C, unless otherwise specified.) Characteristics Symbol Supply Range Vs Total Quiescent Current Iq Input Offset Voltage Non Inverting Input Bias Current Test conditions Min. Typ. ±5 80 Vos -25 Ib Max. Unit ±22.5 V 130 mA +25 mV 500 nA 32 W 25 W 25 W RL=8Ω; 20 W Vs=±16V; RL=4Ω 20 W 0.02 % THD=10%; Music Output Power* Pomax Vs=±22.5V; RL=8Ω; THD=10%; RL=8Ω; Output Power (Continuous RMS) Po Vs=±16V; RL=4Ω 20 THD=1%; RL=8Ω; Po=1W; f=1KHz 0.7 RL=8Ω; % Po=0.1~15W; Total Harmonic Distortion THD f=100Hz~15KHz RL=4Ω; Po=1W; f=1KHz RL=4Ω; Vs=±16V; 0.03 % 1 % Po=0.1~12W; f=100Hz~15KHz (To be continued) HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 2 of 12 SA7265 (Continued) Characteristics Symbol Cross Talk CT Slew Rate SR Open Loop Voltage Gain GV Total Input Noise eN Input Resistance Ri Supply Voltage Rejection (each channel) Thermal Shut-down Junction Temperature SVR Test conditions Min. Typ. Max. Unit f=1KHz 70 dB f=10KHz 60 dB 10 V/µs 80 dB A curve 3 µV f=20Hz~22KHz 4 15 Fr=100Hz; Vripple=0.5Vrms Tj µV 8 20 KΩ 60 dB 145 °C Mute Function [ref: +Vs] Mute /Play Threshold Mute Attenuation VTMUTE -7 -6 AMUTE 60 70 VTST-BY -3.5 -2.5 -5 V dB Stand-by Function [ref: +Vs] Stand-by /Mute Threshold -1.5 V Stand-by Attenuation AST-BY 110 dB Quiescent Current @ Stand-by Iq ST-BY 3 mA Note: * Music Output Power is the maximal power which the amplifier is capable of producing across the rated load resistance (regardless of non linearity) 1 sec after the application of a sinusoidal input signal of frequency 1KHz. According to this definition, the method of measurement comprises the following steps: 1) Set the voltage supply at the maximum operating value -10% 2) Apply a input signal in the form of a 1KHz tone burst of 1 sec duration; the repetition period of the signal pulses is > 60 sec 3) The output voltage is measured 1 sec from the start of the pulse 4) Increase the input voltage until the output signal show a THD = 10% 5) The music power is then Vout2/RL, where Vout is the output voltage measured in the condition of point 4) and R1 is the rated load impedance The target of this method is to avoid excessive dissipation in the amplifier. HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 3 of 12 SA7265 PIN CONFIGURATION PIN DESCRIPTION Pin No. Pin Name Pin Description HSIP-11 HSIP-15 1 2 -Vs 2 3 OUT 1 3 5 +Vs 4 6 OUT 2 5 7 MUTE / ST-BY 6 8 -Vs Negative power 7 9 IN+(2) Inverting Input 2 8 10 IN-(2) Non inverting input 2 9 12 GND Ground 10 13 IN-(1) Non inverting input 1 14 IN+(1) Inverting input 1 1,4,11,15 NC 11 Negative power Output1 Positive power Output2 Mute /stand-by function Not connected FUNCTION DESCRIPTION MUTE AND STAND-BY FUNCTION The pin 5 (MUTE/STAND-BY) controls the amplifier status by two different thresholds, referred to +Vs. - When Vpin5 higher than = +Vs - 2.5V the amplifier is in Stand-by mode and the final stage generators are off - When Vpin5 is between +Vs - 2.5V and +Vs- 6V the final stage current generators are switched on and the amplifier is in mute mode - When Vpin5 is lower than +Vs - 6V the amplifier is play mode. HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 4 of 12 SA7265 BRIDGE APPLICATION Another application suggestion concerns the BRIDGE configuration, where the two power amplifiers are connected as shown by the schematic diagram of the following. This application shows, however, some operative limits due to dissipation and current capability of the output stage. For this reason, we recommend to use the SA7265 in bridge with the supply voltage equal/lower than ±16V when the load is 8Ω; with higher loads (i.e.16Ω), the amplifier can work correctly in the whole supply voltage range. With R1=8Ω, Vs=±16V the maximum output power obtainable is 50W at TDH=10%. The quiescent current remains unchanged with respect to the stereo configuration (~80mA as typical at Vs=±16V). The last point to take into consideration concerns the short-circuit protection. As for the stereo application, the SA7265 is fully protected against any kind of short-circuit (between Out/Gnd, Out/+Vs and Out/-Vs). Power Dissipation and Heat Sinking The SA7265 must always be operated with a heat sink, even when it is not required to drive a load. The idling current of the device is 80mA, so that on a ±20V power supply an unloaded SA7265 must dissipate about 3W of power. The 54°C/W junction-to-ambient thermal resistance of a HSIP-11 package would cause the die temperature to rise 162°C above ambient, so the thermal protection circuitry will shut the amplifier down if operation without a heat sink is attempted. In order to determine the appropriate heat sink for a given application, the power dissipation of the SA7265 in that application must be known. When the load is resistive, the maximum average power that the IC will be required to dissipate is approximately: PD(MAX)=Vs2/π2RL+PQ Where VS is the total power supply voltage across the SA7265, RL is the load resistance PQ is the quiescent power dissipation of the amplifier. The above equation is only an approximation which assume an “ideal”class B output stage and constant power dissipation in all other parts of the circuit. The curves of “Power Dissipation vs. Power Output”give a better representation of the behaviour of the SA7265 with various power supply voltages and resistive loads. As an example, if the SA7265 is operated on a ±20V power supply with a resistive load of 8Ω, it can develop up to 23W of internal power dissipation. If the die temperature is to remain below 150°C for ambient temperatures up to 50°C, the total junction-to-ambient thermal resistance must be less than: (150°C 50°C)/23W 4.3°C/W Using Rth(j-c) = 2°C /W, the sum of the case-to-heat-sink interface thermal resistance and the heat-sink-toambient thermal resistance must be less than 2.3°C/W. The case-to-heat-sink thermal resistance of the HSIP-11 package varies with the mounting method used. A metal-to-metal interface will be about 1°C /W if lubricated, and about 1.2°C /W if dry. If a mica insulator is used, the thermal resistance will be about 1.6°C /W lubricated and 3.4°C /W dry. For this example, we assume a lubricated mica insulator between the SA7265 and the heat sink. The heat sink thermal resistance must then be less than: 4.3°C/W-2°C/W-1.6°C/W 0.7°C/W This is a rather large heat sink and may not be practical in some applications. If a smaller heat sink is required for reasons of size or cost, there is an alternative. The heat sink can be isolated from the chassis so the mica washer is not needed. This will change the required heat sink to a 1.3°C /W unit if the case-to-heat-sink interface is lubricated. The thermal requirements can become more difficult when an amplifier is driving a reactive load. For a given HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 5 of 12 SA7265 magnitude of load impedance, a higher degree of reactance will cause a higher level of power dissipation within the amplifier. As a general rule, the power dissipation of an amplifier driving a 60º reactive load (usually considered to be a worst-case loudspeaker load) will be roughly that of the same amplifier driving the resistive part of that load. For example, a loudspeaker may at some frequency have an impedance with a magnitude of 8Ω and a phase angle of 60º. The real part of this load will then be 4Ω, and the amplifier power dissipation will roughly follow the curve of power dissipation with a 4Ω load. TYPICAL APPLICATION CIRCUIT IN SPLIT SUPPLY Note: Figures for the SA7265. HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 6 of 12 SA7265 TYPICAL APPLICATION CIRCUIT IN SINGLE SUPPLY Note: Figures for the SA7265. TYPICAL BRIDGE APPLICATION CIRCUIT IN SPLIT SUPPLY Note: Figures for the SA7265. HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 7 of 12 SA7265 THD(%) THD(%) Ampl.(dB) Pout(W) Pout(W) Iq(mA) ELECTRICAL CHARACTERISTICS CURVES (To be continued) HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 8 of 12 SA7265 Attenuation (dB) Pdlss(W) Pdlss(W) Iq(mA) (Continued) PC BOARD AND COMPINENTS LAYOUT OF THE TYPICAL APPLICATION IN SPLIT SUPPLY HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 9 of 12 SA7265 APPLICATION SUGGEST The recommended values of the external components are those shown are the Typical Application Circuit in Split Supply: COMPONENTS RECOMMENDED VALUE PURPOSE R1 10KΩ Mute Circuit R2 15KΩ Mute Circuit R3 18KΩ Mute Circuit R4 15KΩ Mute Circuit R5, R8 18KΩ Closed R6, R9 560Ω R7 R10 4.7Ω C1, C2 1µF Loop Gain Setting* Frequency Stability LARGER THAN SMALLER THAN RECOMMENDED VALUE RECOMMENDED VALUE Increase of Dz Biasing Current VMUTE/STBY Shifted Downward VMUTE/STBY Shifted Upward Shifted Upward VMUTE/STBY VMUTE/STBY VMUTE/STBY Shifted Downward Shifted Upward VMUTE/STBY Shifted Downward Increase of Gain Decrease of Gain Danger of Oscillations Danger of Oscillations Input DC Higher Low Frequency Decoupling Cutoff St-By/Mute C3 1µF Time Larger On/Off Time Smaller On/Off Time Constant Supply C4, C6 1000µF C5, C7 0.1µF C8, C9 0.1µF Dz 5.1V Mute Circuit Q1 BC107 Mute Circuit * Closed loop gain has to be Bypass Supply Bypass Danger of Oscillations Frequency Stability 25dB HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn Danger of Oscillations REV:1.2 2006.05.25 Page 10 of 12 SA7265 PACKAGE OUTLINE HSIP-11 Unit: mm HSIP-15 Unit: mm HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.05.25 Page 11 of 12