AW8738 Data Sheet June 2015 V1.1 Multi-Level AGC K Multi-Level AGC AW8738 40V 0.008% K AW8738 Multi-Level 83% AGC 0.6W0.8W1W 1.2W AW8738 93% K-Chargepump 6 83%AW8738 40V 99.6dB AW8736AW8737 (SNR) 0.008% TDD-Noise Multi-Level AGC pop-click AW8738 0.6W0.8W1W 1.2W PSRR-68dB217Hz Multi-Level AGC ESD 8kV (HBM) AW8738 2mmx2mm FC-16 AW8736AW8737 3.3V-4.35V AW8738 TDD-Noise EMI TDD-Noise EMI AW8738 AW8738 2mmx2mm FC-16 VBAT CS1 4.7uF A3,B3 D2 C1 C1P C1N VDD A4 Pulse Input 1 2 3 4 5 6 CF2 2.2uF CF1 2.2uF CS2 0.1uF D1 C2P SHDN B1,B2 C2N PVDD D3 COUT 4.7uF 10V 7 33nF 3K Cin Rin A2 INN AW8738 Cd 220pF Cin 33nF A1 Rin VOP B4 B1 INP 3K VON C2 1nF D4 B2 C3 1nF GND C2,C3,C4 1 AW8738 www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 1 AW8738 Data Sheet June 2015 V1.1 High efficiencyLow noiseConstant large volumeMulti-level AGC Eighth generation Class K Audio Amplifier FEATURES DESCRIPTION Multi-Level AGC audio algorithm effectively eliminate noise, make sound pure natural Low noise40V Ultra-low distortion0.008% Power amplifier overall efficiency is up to 83% Selectable speaker-guard power level0.6W0.8W 1W1.2W Within Lithium battery voltage range, maintained constant large volume Support 6ohm speaker Compatible with AW8736AW8737 Super TDD-Noise suppression Excellent pop-click suppression One wire pulse control High PSRR-68dB217Hz ESD protection8kV (HBM) Small 2mmx2mm FC-16package AW8738 is specifically designed to eliminate smart mobile phone music noise, to enhance overall sound quality, which is a new high efficiency, low noise, ultra-low distortion, constant large volume, eighth generation class K audio amplifiers. AW8738 integrated Awinic proprietary multi-level AGC audio algorithm, effectively eliminate music noise, improve sound quality and volume. Using a new generation 93% efficiency K-Chargepump, power amplifiers overall efficiency reaches 83%, greatly prolong the mobile phone usage time. AW8738 noise floor is as low as to 40uV, with 99.6dB high signal-to-noise-ratio(SNR). The ultra-low distortion 0.008% and unique multi-level AGC technology brings high quality music enjoyment. AW8738 has 0.6W, 0.8W, 1W and 1.2W four selectable speaker-guard output power levels, which is suitable for different rated power speakers, greatly improve the volume, effectively protect speakers. With multi-level AGC audio algorithms, the music is pure natural and melodious. AW8738 is compatible with AW8736, AW8737, output power cannot drop along with lithium battery voltage lower down. Within lithium battery voltage range(3.3V-4.35V), output power is constant. The AW8738 uses Awinic proprietary TDD-Noise suppression technology and EMI suppression technology, effectively restrain TDD-Noise and EMI interference. AW8738 built-in over current protection, over-temperature protection and short circuit protection function, effectively protect the chip. The AW8736 uses small 2mmx2mm FC-16 package. APPLICATIONS Smart phone APPLICATION DIAGRAM VBAT CS1 4.7uF A3,B3 D2 C1 C1P C1N VDD A4 Pulse Input 1 2 3 4 Single-Ended Input 33nF Cin 6 5 33nF D1 C2P SHDN B1,B2 C2N PVDD D3 COUT 4.7uF 10V 7 3K A2 INN Rin AW8738 Cd 220pF Cin CF2 2.2uF CF1 2.2uF CS2 0.1uF Rin A1 VOP B4 B1 INP 3K VON C2 1nF D4 B2 C3 1nF GND C2,C3,C4 Figure1 AW8738 application diagram All trademarks are the property of their respective owners. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 2 AW8738 Data Sheet June 2015 V1.1 PIN CONFIGURATION ANG TOP MARK AW8738FCR TOP VIEW AW8738FCR MARKING D C2P C1P PVDD VON D C C1N GND GND GND C 8738 B C2N C2N VDD VOP B XXXX A INP INN VDD SHDN A 1 2 3 4 1 Please notice the pin number Figure 2 2 3 4 8738 - AW8738FCR XXXX-Production tracking code AW8738FCR pin diagram top view and device marking PIN DESCRIPTION Number A1 A2 A3B3 A4 B1 B2 B4 C1 C2 C3 C4 D1 D2 D3 D4 Symbol INP INN VDD SHDN Description Positive audio input terminal Negative audio input terminal Power supply Chip power down pinactive lowone wire pulse control C2N Negative side of the external charge pump flying capacitor C2 VOP C1N Positive audio output terminal Negative side of the external charge pump flying capacitor C1 GND Ground C2P C1P PVDD VON Positive side of the external charge pump flying capacitor C2 Positive side of the external charge pump flying capacitor C1 Boost charge pump output voltage Negative audio output terminal AWINIC CLASS K FAMILY ITEM PVDD(V) Ouput noise(V) Efficiency(%) TEST CONDITION AW8736 AW8737 AW8738 VDD>3.8V(AW8736)VDD>4V(AW8737/8738) 5.8 6.05 6.05 VDD=4.2Vf=20Hz to 20kHzinput ac grounded 8V/V,A-weighting 125 52 40 VDD=3.6VPo=1.0WRL=8+33H 75 80 83 www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 3 AW8738 Data Sheet June 2015 V1.1 FUNCTIONAL DIAGRAM C1P VDD C1N C2P C2N SHDN OVP SHDN&BIAS PVDD K-Chargepump Current Limit SEGMENTED OTP OSC Multi-level AGC VOP INP INPUT BUFFER Ultra Low EMI output stage Class-K Modulator INN VON OCP Noise Cancellor NCN AW8738 GND Figure 3 AW8738 functional diagram APPLICATION DIAGRAM VBAT CS1 4.7uF A3,B3 D2 C1 C1P C1N VDD A4 Pulse Input 1 2 3 4 5 Single-Ended Input 33nF Cin 6 33nF D1 C2P SHDN B1,B2 C2N PVDD 3K A2 COUT 4.7uF 10V INN Rin Rin D3 7 AW8738 Cd 220pF Cin CF2 2.2uF CF1 2.2uF CS2 0.1uF A1 VOP B4 B1 INP 3K VON C2 1nF D4 B2 C3 1nF GND C2,C3,C4 Figure 4 AW8738 single-ended input application diagram (Note 1) Note1when single-ended inputinput audio signal can arbitrarily connect to one of INNINP input terminalthe other terminal connects to ground through input capacitor and resistance. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 4 AW8738 Data Sheet June 2015 V1.1 VBAT CS1 4.7uF A3,B3 D2 C1 C1P C1N VDD Pulse Input 1 2 Differential Input A4 3 4 5 6 7 33nF 3K Cin Rin A2 33nF B1,B2 C2N PVDD D3 COUT 4.7uF 10V INN AW8738 A1 Rin D1 C2P SHDN Cd 220pF Cin CF2 2.2uF CF1 2.2uF CS2 0.1uF VOP B4 B1 INP 3K VON C2 1nF D4 B2 C3 1nF GND C2,C3,C4 Figure 5 AW8738 differential input application diagram ORDERING INFORMATION Product Type Operation temperature range Package Device Marking Delivery Form AW8738FCR -4085 FC-16 8738 Tape and Reel 3000 pcs AW8738 Shipment R: Tape & Reel Package type FC: FC16 ABSOLUTE MAXIMUM RATING(Note2) Parameter Range -0.3V to 6V Supply Voltage VDD -0.3V to VDD+0.3V INPINN Input Pin Voltage 69/W Package Thermal Resistance JA -40 to 85 Ambient Temperature Range 125 Maximum Junction Temperature TJMAX www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 5 AW8738 Data Sheet June 2015 V1.1 -65 to 150 Storage Temperature Range TSTG 260 Lead TemperatureSoldering 10 Seconds ESD Rating Note 3 HBMhuman body model 8KV Latch-up +IT450mA Test ConditionJEDEC STANDARD NO.78B DECEMBER 2008 -IT-450mA Note 2Stresses beyond those listed under "absolute maximum ratings" may cause permanent damageto the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. Note 3The human body model is a 100pF capacitor discharged through a 1.5k resistor into each pin. Test method: MIL-STD-883G Method 3015.7 MODE DESCRIPTION(TA=25,VDD=4.2V) AW8738 audio amplifier outer input capacitor is Cinouter input resist is Rininner input resist is 6.6Kgain Av is 159.5K/(Rin+6.6K). Recommended typical application is 1 Cin=33nFRin=3KAv=16.6V/V MODE Enable Signal Gain V/V NCN PowerW RL=8+ 33H RL=6+ 33H RL=4+ 15H RL=3+ 15H NCN function Multi-Level AGC function MODE1 16.6 1.2 -- 2.4 -- MODE 2 16.6 1 -- 2 -- MODE 3 16.6 0.8 1 1.6 2 MODE 4 16.6 0.6 0.8 1.2 1.6 MODE 5 16.6 0.8 1 1.6 2 MODE 6 16.6 0.6 0.8 1.2 1.6 MODE 7 16.6 1.83W@ THD=1% 2.25W@ THD=1% 2.6W@ THD=1% www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 6 AW8738 Data Sheet June 2015 V1.1 ELECTRICAL CHARACTERISTICS Test conditionTA=25, VDD=3.6VRL=8+33Hf=1kHzunless otherwise noted Parameter Test conditions Min Typ Max Units VDD Power supply voltage 3.0 5.5 V VIH SHDN high input voltage 1.3 VDD V VIL SHDN low input voltage 0 0.35 V 30 mV 1 A |VOS| Output offset voltage Vin=0VVDD=3.0V to 5.5V -30 ISD Shutdown current VDD=3.6V SHDN =0V TTG Thermal AGC start temperature threshold 150 TTGR Thermal AGC exit temperature threshold 130 TSD Over temperature protection threshold 160 TSDR Over temperature recovery threshold 120 TON Start-up time 40 ms protection 0 K-Chargepump 1.5* VDD =3.0V to 4.0V PVDD V VDD Output voltage VDD >4V 6.05 V OVP hysteresis VDD >4V 50 mV FCP Charge Pump frequency VDD=3.0V to 5.5V CP Charge pump efficiency VDD=4.2V, Iload=200mA TST Soft-start time No loadCOUT=4.7F Vhys IL 0.8 1.06 1.33 93 1 Current limit when PVDD short to ground 1.2 MHz % 1.4 ms 350 mA VDD=3.6VVin=0no load 12 mA VDD=3.6VPo=1.0WRL=8+33H 83 % VDD=3.6VPo=1.0WRL=6+33H 84 % Class K power amplifiermode1-mode4 Iq Quiescent current Efficiency Fosc Modulation frequency VDD=3.0V to 5.5V 600 Av gain Outside input resistance=3k Vin Recommend input voltage VDD=3.0V to 5.5V Rini Inner input resistance 800 1000 16.6 kHz V/V 1 Vp 6.6 k VDD=4.2VRL=8+33H 1.2 W VDD=4.2VRL=4+15H 2.4 W VDD=4.2VRL=8+33H 1 W VDD=4.2VRL=4+15H 2 W VDD=4.2VRL=8+33H 0.8 W VDD=4.2VRL=6+33H 1 W VDD=4.2VRL=4+15H 1.6 W Mode1 NCN output power Mode2 NCN output power Pncn Mode3 NCN output power www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 7 AW8738 Data Sheet June 2015 V1.1 Parameter Mode4 NCN output power Pncn Mode5 Multi-level AGC output power Mode6 Multi-level AGC output power PSRR SNR Power supply rejection ratio Signal-to-noise ratio Test conditions Min Output noise voltage PO Total harmonic distortion+noise Units 0.6 W VDD=4.2VRL=6+33H 0.8 W VDD=4.2VRL=4+15H 1.2 W VDD=4.2VRL=8+33H 0.8 W VDD=4.2VRL=6+33H 1 W VDD=4.2VRL=4+15H 1.6 W VDD=4.2VRL=8+33H 0.6 W VDD=4.2VRL=6+33H 0.8 W VDD=4.2VRL=4+15H 1.2 W 217Hz -68 -58 dB 1kHz -68 -58 dB VDD=4.2VVp-p_sin=200mV VDD=4.2VPo=1.83WTHD=1%RL=8+33H, Av=8V/V 99.6 dB VDD=4.2VPo=2.25WTHD=1%RL=8+33H Av=8V/V 99.3 dB 40 Vrms 45 Vrms 56 Vrms VDD=4.2V,Po=1W,RL=8+33H,f=1kHz,Mode7 0.008 % VDD=4.2V,Po=1.2W,RL=8+33H,f=1kHz,Mode7 0.009 % THD+N=10%f=1kHzRL=8+33HVDD=4.2V 2.3 W THD+N=1%f=1kHzRL=8+33HVDD=4.2V 1.83 W THD+N=10%f=1kHzRL=8+33HVDD=3.6V 1.6 W THD+N=1%f=1kHzRL=8+33HVDD=3.6V 1.35 W THD+N=10%f=1kHzRL=6+33HVDD=4.2V 2.77 W THD+N=1%f=1kHzRL=6+33HVDD=4.2V 2.25 W THD+N=10%f=1kHzRL=6+33HVDD=3.6V 2.05 W THD+N=1%f=1kHzRL=6+33HVDD=3.6V 1.63 W THD+N=10%f=1kHzRL=4+15HVDD=4.2V 3.2 W THD+N=1%f=1kHzRL=4+15HVDD=4.2V 2.6 W THD+N=10%f=1kHzRL=4+15HVDD=3.6V 2.35 W THD+N=1%f=1kHzRL=4+15HVDD=3.6V 1.92 W VDD=4.2Vf=20Hz to 20kHzinput ac groundedAv=12V/V A-weighting VDD=4.2Vf=20Hz to 20kHzinput ac groundedAv=16V/V THD+N Max VDD=4.2VRL=8+33H VDD=4.2Vf=20Hz to 20kHzinput ac groundedAv=8V/V Vn Typ Mode4 output power One wire pulse control TH SHDN high level duration time VDD=3.0V to 5.0V 0.75 2 10 s TL SHDN low level duration time VDD=3.0V to 5.0V 0.75 2 10 s TLATCH SHDN turn on delay time VDD=3.0V to 5.0V 150 500 s TOFF SHDN turn off delay time VDD=3.0V to 5.0V 150 500 s www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 8 AW8738 Data Sheet June 2015 V1.1 Parameter Note NCN Test conditions Min Typ Max Units 4 TAT Attack time -13.5dB gain attenuation completed 40 ms TRL Release time 13.5dB gain release completed 1.2 s AMAX Maximum attenuation -13.5 dB Dual Level Dual Rate AGC Note 5 TATF Fast attack time -13.5dB gain attenuation completed 1.5 ms TATS Slow attack time -13.5dB gain attenuation completed 6 ms TATT Total attack time -13.5dB gain attenuation completed 7.5 ms TRL Release time 13.5dB gain release completed 280 ms AMAX Maximum attenuation -13.5 dB Note 4, Note 5Attack time points to 13.5dB gain attenuation timeRelease time points to 13.5dB gain recovery time. MEASUREMENT SETUP AW8738 features switching digital output, as shown in Figure 6. Need to connect a low pass filter to VOP/VON output respectively to filter out switch modulation frequency, then measure the differential output of filter to obtain analog output signal. 10nF 500 VOP INP Cin Rin 30kHz Low-Pass Fliter AW8738 VON INN Cin 500 Rin 10nF Figure 6 AW8738 test setup Low pass filter uses resistance and capacitor values listed in Table 1. Rfilter Cfilter Low-pass cutoff frequency 500 10nF 32kHz 1k 4.7nF 34kHz Table 1 AW8738 recommended values for low pass filter Output Power Calculation According to the above test methods, the differential analog output signal is obtained at the output of the low pass filter. The valid values Vo_rms of the differential signal as shown below: www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 9 AW8738 Data Sheet June 2015 V1.1 Vo_rms The power calculation of Speaker is as follows PL www.awinic.com.cn (Vo _ rms )2 RL R Lload impedance of the speaker COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 10 AW8738 Data Sheet June 2015 V1.1 TYPICAL CHARACTERISTICS Efficiency vs PO Efficiency vs PO 100 100 90 90 VDD=3.6V 80 80 VDD=4.2V 70 Efficiency( % ) Efficiency( % ) VDD=3.6V 60 50 40 VDD=4.2V 70 60 50 40 30 30 20 20 RL=8+33H 10 RL=6+33H 10 0 0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 0 2 0.2 0.4 0.6 0.8 1.2 1.6 1.8 2 1.4 AW8738 PO keep constant AW8738 PO keep constant MODE1 1.2 NCN Output Power( W ) 1.2 MODE2 1.0 MODE3MODE5 0.8 MODE4MODE6 0.6 0.4 MODE3MODE5 1.0 MODE4MODE6 0.8 0.6 0.4 0.2 0.2 RL=6+33H RL=8+33H 0 0 3.3 3.5 3.7 3.9 3.3 4.3 4.1 3.5 3.7 GAIN vs FREQUENCY 20 24 Rine=3k Cin=1F RL=8+33H 22 20 18 16 16 Gain( V/V ) 18 14 12 10 12 10 8 6 6 4 4 2 2 100 10K 1K 20K 50 Frequency ( Hz ) www.awinic.com.cn Rine=3k Cin=1F RL=6+33H 14 8 50 4.3 4.1 GAIN vs FREQUENCY 24 22 3.9 VDD ( V ) VDD ( V ) Gain( V/V ) 1.4 OUTPUT POWER vs VDD OUTPUT POWER vs VDD 1.4 NCN Output Power( W ) 1 PO ( W ) PO ( W ) 100 1K 10K 20K Frequency ( Hz ) COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 11 AW8738 Data Sheet June 2015 V1.1 THD+N vs FREQUENCY THD+N vs FREQUENCY 10 10 MODE7 Po=0.8W VDD=4.2V Rine=3k Cin=1F RL=8+33H 1 THD+N (%) THD+N (%) 1 0.1 0.1 0.01 0.01 0.001 0.001 50 MODE7 Po=0.8W VDD=4.2V Rine=3k Cin=1F RL=6+33H 100 10K 1K 50 20K 100 THD+N vs PO THD+N vs PO 10 10 Mode7 f=1kHz Cin=1F RL=8+33H Mode7 f=1kHz Cin=1F RL=6+33H 1 THD+N (%) THD+N (%) 1 VDD=3.6V VDD=4.2V 0.1 0.01 VDD=3.6V VDD=4.2V 0.1 0.01 0.001 0.1 1 0.5 2 0.001 0.1 3 0.5 PO( W ) 1 2 3 PO( W ) PO vs VIN PO vs VIN 2 Mode1 VDD=4.2V f=1kHz RL=8+33H 1 Mode2 VDD=4.2V f=1kHz RL=8+33H 1 NCN PO (W) PO (W) 20K Frequency ( Hz ) Frequency ( Hz ) 2 10K 1K 0.5 1.30 0.28 0.1 0.5 1 2 0.1 Vp www.awinic.com.cn 1.20 0.25 0.1 0.1 NCN 0.5 0.5 1 2 Vp COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 12 AW8738 Data Sheet June 2015 V1.1 PO vs VIN 2 PO vs VIN 2 Mode3,Mode5 VDD=4.2V f=1kHz RL=8+33H 1 PO (W) PO (W) 1 Mode4,Mode6 VDD=4.2V f=1kHz RL=8+33H NCN 0.5 0.23 0.5 NCN 1.07 0.20 0.93 0.1 0.1 0.5 0.1 1 0.5 0.1 2 PO vs VIN PO vs VIN 2 Mode3,Mode5 VDD=4.2V f=1kHz RL=6+33H Mode4,Mode6 VDD=4.2V f=1kHz RL=6+33H 1 PO (W) PO (W) 1 NCN 0.5 0.23 0.5 1.07 NCN 0.20 0.93 0.1 0.1 0.5 0.1 1 0.5 0.1 2 1 2 Vp Vp PSRR vs FREQUENCY PSRR vs FREQUENCY 0 0 Mode1 Rine=3k Cin=1F RL=8+33H -10 -20 Mode7 Rine=3k Cin=1F RL=8+33H -10 -20 -30 -30 PSRR (dB) PSRR (dB) 2 Vp Vp 2 1 -40 -50 VDD=3.6V VDD=4.2V -40 -50 -60 -60 -70 -70 -80 -80 -90 VDD=4.2V VDD=3.6V -90 20 100 1K 10K 20K 20 Frequency ( Hz ) www.awinic.com.cn 100 1K 10K 20K Frequency ( Hz ) COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 13 AW8738 Data Sheet June 2015 V1.1 SHUTDOWN SEQUENCE START-UP SEQUENCE SHDN SHDN VOP&VON 100s/div VOP&VON 10ms/div SINGLE-LEVEL-AGC SINGLE-LEVEL-AGC Vin Vin VOP-VON VOP-VON 200ms/div 10ms/div MULTI-LEVEL-AGC MULTI-LEVEL-AGC Vin Vin VOP-VON VOP-VON 100ms/div 5ms/div www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 14 AW8738 Data Sheet June 2015 V1.1 DETAILED FUNCTIONAL DESCRIPTION AW8738 is specifically designed to eliminate smart mobile phone music noise, to enhance overall sound quality, which is a new high efficiency, low noise, ultra-low distortion, constant large volume, eighth generation class K audio amplifiers. AW8738 integrated Awinic proprietary multi-level AGC audio algorithm, effectively eliminate music noise, improve sound quality and volume. Using a new generation 93% efficiency K-Chargepump, power amplifiers overall efficiency reaches 83%, greatly prolong the mobile phone usage time. AW8738 noise floor is as low as to 40V, with 99.6dB high signal-to-noise-ratio(SNR). The ultra-low distortion 0.008% and unique multi-level AGC technology brings high quality music enjoyment. AW8738 has 0.6W, 0.8W, 1W and 1.2W four selectable speaker-guard output power levels, which is suitable for different rated power speakers, greatly improve the volume, effectively protect speakers. With multi-level AGC audio algorithms, the music is pure natural and melodious. AW8738 is compatible with AW8736, AW8737, output power cannot drop along with lithium battery voltage lower down. Within lithium battery voltage range(3.3V-4.35V), output power is constant. The AW8738 built in excellent pop-click noise suppression circuit, effectively avoids pop-click noise during shutdown, wakeup, and power-up/down operation of AW8738. The AW8738 uses Awinic proprietary TDD-Noise suppression technology and EMI suppression technology, effectively restrain TDD-Noise and EMI interference. AW8738 built-in over current protection, over-temperature protection and short circuit protection function, effectively protect the chip. The AW8736 uses small 2mmx2mm FC-16 package. CONSTANT OUTPUT POWER In the mobile phone audio applications, the NCN function to promote music volume and quality is very attractive, but as the lithium battery voltage drops, general power amplifier output power will reduce gradually, leads to smaller and smaller music volume. So, it is hard to provide high quality music within the battery voltage range. The AW8738 uses unique second generation NCN technology, within lithium battery voltage range(3.3V-4.35V), output power is constant, the output power cannot drop along with lithium battery voltage lower down. Even if the battery voltage drops, AW8738 can still provide high quality large volume music enjoyment. There are seven AW8738 operation modes, first four modes have NCN function, the output power level is 1.2W,1W,0.8W, 0.6W,respectively. The five and six modes have Multi-level AGC function, the output power level is 0.8W, 0.6W,respectively. Second Generation NCN technology In audio application, output signal will be undesirable distortion caused by too large input and power supply voltage down with battery, and clipped output signal may cause permanent damage to the speaker. The traditional NCN function adjusts system gain automatically to generate desired output by detecting the "Crack" distortion of output signal, makes the output audio signal maintain smooth, not only can effectively avoid overloading output power to the damage of speaker, at the same time bring the constant shock of high quality music enjoyment. The traditional NCN function is shown below in figure 7. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 15 AW8738 Data Sheet June 2015 V1.1 Crack Noise Battery Voltage NCNOFF NCNON Crack Noise Battery Voltage NCNOFF Figure 7 NCNON Traditional NCN Operation Principle AW8738 adopts Awinic unique second generation NCN technology, the output signal is free from limitation of power rail. When battery voltage drops, NCN output signal will not distort, output amplitude remains unchanged, keeping constant output power, as shown in figure 8. Even if the battery voltage drops, AW8738 can still provide high quality large volume music enjoyment. Supply Rail Battery Voltage Traditional NCN function Constant output power Second Generation NCN funciton Figure 8 Second generation NCN Operation Principle Attack time Attack time is the time it takes for the gain to be attenuated -13.5dB once the audio signal exceeds the NCN threshold. Fast attack times allow the NCN to react quickly and prevent transients such as symbol crashes from being distorted. However, fast attack times can lead to volume pumping, where the gain reduction and release becomes noticeable, as the NCN cycles quickly. Slower attack times cause the NCN to ignore the fast transients, and instead act upon longer, louder passages. Selecting an attack time that is too slow can lead to increased distortion in the case of the No Clip function. According to mobile phone and portable equipment audio features, attack time of AW8738 is set to be 40ms, effectively keeping the music rhythm, and at the same time eliminating the crack distortion, protecting the speaker. Release time Release time is the time it takes for the gain to return to its normal level once the audio signal returns below the NCN threshold. A fast release time allows the NCN to react quickly to transients, preserving the original dynamics of the audio source. However, similar to a fast attack time, a fast release time contributes to volume pumping. A slow release time makes the music smooth and soft, it is better to suppress the crack distortion, but longer release time will make music sounds "boring" ,lack of impact. According to mobile phone and portable equipment audio features, release time of AW8738 is set to be 1.2s. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 16 AW8738 Data Sheet June 2015 V1.1 Multi-level AGC technology In the actual audio application, system output power tends to be more than rated power of speaker, such as in the 5V power supply, as for 8ohms speaker, the maximum undistorted power is about 1.56W, but many speakers rated power is about 0.5W, if there is no output power control, the overload signal can cause damage to the speaker. The audio power amplifier with NCN function (that is single-level AGC) can protect the speaker effectively, with the increase of input signal, the output power increases. When output power exceeds the setting threshold, the NCN function reduces the internal gain of amplifier and restricts the output power under the set threshold. But the NCN function has the attack time setting, which is the tradeoff between auditory effect and crack distortion noise, if the attack time is longer, the audio volume will be greater, but crack distortion will also increase; if the attack time is shorter, the crack distortion will decrease, but the audio volume will be reduced. General music has large peak factor, which is in the range of about 40~60dB, when playing music, the big peak signal output exceeds the maximum output amplitude, there will be more crack distortion, and obvious noise will be heard in some music, so it is need to use multi-level AGC technology to dynamically adjust the audio power amplifier, to increase music volume, at the same time, eliminate the emergence of obvious noise in large volume music and improve sound quality. AW8738 integrated Awinic proprietary multi-Level AGC algorithm technology, effectively eliminating the noise in the music, make sound pure natural, and greatly enhancing the sound volume. The single-level AGC function and multi-level AGC function is shown in figure 9. Single-level AGC Multi-level AGC Constant output power threshold voltage Constant output power threshold voltage More Crack Distortion Few Of Crack Distortion Single-level AGC function: detect constant output voltagewithin attack timeoutput has more crack distortion, and more noise Figure 9 Crack distortion voltage Multi-level AGC function: simultaneously detect crack distortion voltage and constant output voltage, within attack time, output has few of crack distortion, effectively eliminate noise Single-level AGC/Multi-level AGC Operation Principle Attack time Attack time is the time multi-level AGC takes for the gain to be attenuated -13.5dB once the audio signal exceeds the constant output power threshold voltage. When the output signal crack noise occurred, the Fast AGC of Multi-level AGC launched, attenuated the gain with 10dB within 1.5ms. When the crack noise eliminated, the Slow AGC of Multi-level AGC launched, attenuated the gain slowly, with 3.5dB within 6ms. According to smart mobile phone music noise features and demands for improve music quality and volume, adoption of the Awinic proprietary technology Multi-level AGC inside AW8738, which keeping the music rhythm effectively, and at the same time eliminating the crack distortion, protecting the speaker. Release time Release time is the time multi-level AGC takes for the gain to return to its normal level once the audio signal is smaller than crack distortion voltage or constant output power threshold voltage. According to smart mobile phone music noise features and demands for improve music quality and volume, release time of AW8738 is set to be 280ms, which can effectively eliminate the noise, make music sound pure natural. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 17 AW8738 Data Sheet June 2015 V1.1 K-Chargepump AW8738 adopts a new generation of charge pump technologyK -Chargepump structure, it has high efficiency and large driving ability, working frequency is 1.1MHzbuilt in soft start circuit, current limiting control loop and over-voltage-protection(OVP) loop, guaranteeing system stable and reliable operation. High Efficiency AW8738 uses K-chargepump structurebooster output voltage PVDD is 1.5 times of supply voltage VDD, the ideal efficiency can reach 100%. K-chargepump efficiency is the ratio of output power to input power, that is POUT *100 % PIN For example, in an ideal M times charge pump, the input current IIN is M times of output current IOUTthe efficiency formula can be written as POUT V *I V *100 % OUT OUT *100 % OUT *100 % PIN VIN * M * I OUT M *VIN M is charge pump work mode variable (1.5 times), VOUT is charge pump output voltage, VIN is power supply voltage, IOUT is load current. For K-chargepump, the output voltage is 1.5 times of the input voltage, due to the charge pump internal switch loss and IC static current loss, the actual efficiency will be up to 93%. Therefore, K-chargepump booster technology can greatly improve the power efficiency. Charge Pump Structure Figure 10 is charge pump basic principle diagram, the charge pump used in AW8738 has seven switches, the output voltage PVDD is 1.5 times as input voltage VDD through seven switches timing control. S1 C1P + VDD CIN 4.7uF S6 CF1 2.2uF S4 PVDD COUT 4.7uF C1N S2 + S7 C2P CF2 2.2uF S5 S3 C2N Figure 10 Charge Pump Principle Diagram The operation of the charge pump has two phases. In 1, as shown in figure 11, swtiches S1, S2 and S3 are closed, VDD charges to the flying capacitor CF1 CF2. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 18 AW8738 Data Sheet June 2015 V1.1 S1 C1P + VDD CIN 4.7uF S6 CF1 2.2uF S4 PVDD COUT 4.7uF C1N S2 + S7 C2P CF2 2.2uF S3 S5 C2N Charging Phase 1: Flying Capacitor Charging Figure 11 In 2, as shown in figure 12: switches S1, S2 and S3 are disconnected, switches S4, S5, S6 and S7 are closed. Because the voltage across the capacitor can't mutation, so the voltage on flying capacitor CF1 CF2, is added to the VDD, which make PVDD risen to a higher voltage. S1 C1P + VDD CIN 4.7uF S6 CF1 2.2uF S4 PVDD COUT 4.7uF C1N S2 + S7 C2P CF2 2.2uF S3 S5 C2N Discharging Phase Figure 12 2 Flying capacitor charge transfer to the output capacitance COUT Soft start K-chargepump has integrated soft start function in order to limit supply power inrush current during start-up. The supply current is limited to be 350 mA, and the soft start time is 1.2 ms. Current Limitation Control K-chargepump has integrated the current limitation control loop. In normal operation, when the heavy load or a situation that make charge pump flow through very large current, the current limitation control loop will control charge pump maximum output current capacity, that is 2A. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 19 AW8738 Data Sheet June 2015 V1.1 Over Voltage Protection(OVP)Control K-chargepumps output voltage PVDD is a multiple of the input voltage VDD, which provide a high voltage rail for internal power amplifier circuits, allowing the amplifiers provide greater output dynamic range in the lithium battery voltage range, so as to realize the large volume, high quality class K audio enjoyment. K-chargepump has integrated the over voltage protection control loop, when the input voltage VDD is greater than 4V, the output voltage PVDD is no longer a multiple of VDD, but is controlled by over voltage protection(OVP) loop and is stable in 6.05V, and the hysteresis voltage is about 50mV. One-wire pulse control One wire pulse control technology only needs a single GPIO port to operate the chip, complete a variety of functions, it is very popular in the area of the GPIO port shortage and portable systems. When the control signal line is longer, because of the signal integrity or radio frequency interference problem, it will produce the narrow glitch signal. Awinic one wire pulse control technology integrated the Deglitch circuit in internal control pin, which can effectively eliminate the influence of the glitch signal, as shown in figure 13. AW8738 SHDN Deglitch Control signal with glitch Glitch is eleminated Figure 13 Awinic Deglitch function diagram The traditional one wire pulse control technology still receives pulse signal from control port when chip is startup, so when the master control chip (such as mobile phone BB) sends wrong pulse during normal operation, the system will enter into error states. AW8738 uses one wire pulse latch technology, after the master control chip has sent pulses, the state will be latched, no longer receive the latter mis-sending pulse signals, as shown in figure 14. TLATCH STATE 4 STATE 3 Traditional One Wire Pulse Control Shielding abnormal pulse signal STATE 4 STATE 3 Anti-interference One Wire Pulse Control Figure 14 Anti-interference One Wire Pulse Control Function Diagram One Wire Pulse Control AW8738 select each mode through the detection of number of the pulse signal rising edge of SHDN pin, as shown in figure 15: When SHDN pin pull high from shutdown mode, there is only a rising edge, AW8738 enter into mode 1,NCN output power is 1.2W; When high-low-high signal set to SHDN pin, there www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 20 AW8738 Data Sheet June 2015 V1.1 are two rising edges, AW8738 enter into mode 2, NCN output power is 1W; When there are three rising edges, AW8738 enter into mode 3,NCN output power is 0.8W; When there are four rising edges, AW8738 enter into mode 4, NCN output power is 0.6W; AW8738 has seven operation modes, the number of the rising edges does not allow more than seven. MODE1 MODE2 MODE3 MODE4 TH TL 0.75s<TL,TH<10s TOFF Figure 15 One Wire Pulse Control When AW8738 needs to work in different mode, PIN SHDN should be pull low longer than TOFF first(recommended 1ms) which make the AW8738 shut down, Then send series pulse make the AW8738 enter into right mode, as shown in figure 16. SHDN 1ms MODE2 MODE3 Figure 16 One Wire Pulse Control Switching Sequence RNS(RF TDD Noise Suppression) GSM radios transmit using time-division multiple access with 217Hz intervals. The result is an RF signal with strong amplitude modulation at 217Hz and its harmonics that is easily demodulated by audio amplifiers. In RF applications, improvements to both layout and component selection decrease the AW8738s susceptibility to RF noise and prevent RF signals from being demodulated into audible noise. Minimizing the trace lengths prevents them from functioning as antennas and coupling RF signals into the AW8738. Additional RF immunity can also be obtained from relying on the self-resonant frequency of capacitors as it exhibits the frequency response similar to a notch filter. Depending on the manufacturer, 10pF to 20pF capacitors typically exhibit self resonance at RF frequencies. These capacitors, when placed at the input pins, can effectively shunt the RF noise at the inputs of the AW8738. For these capacitors to be effective, they must have a low-impedance, low-inductance path to the ground plane. Some RF energy will couple onto audio traces regardless of the effort to prevent this phenomenon from occurring, form audible TDD NoiseThe AW8738 features a unique RNS technology, which effectively reduces RF energy, attenuate the RF TDD-noise, an acceptable audible level to the customer. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 21 AW8738 Data Sheet June 2015 V1.1 VDD Cin INP VOP INN AW8738 VON Rin GND Figure 17 RF Radiation coupling schematic diagram Filter-Free Modulation Scheme The AW8738 features a filter-free PWM architecture that reduces the LC filter of the traditional Class-D amplifier, increasing efficiency, reducing board area consumption and system cost. EEE The AW8738 features a unique Enhanced Emission Elimination (EEE) technology, that controls fast transition on the output, greatly reduces EMI over the full bandwidth. Pop-Click Suppression The AW8738 features unique timing control circuit, that comprehensively suppresses pop-click noise, eliminates audible transients on shutdown, wakeup, and power-up/down. Protection Function When a short-circuit occurs between VOP/VON pin and VDD/GND or VOP and VON, the over-current circuit shutdown the device, preventing the device from being damaged. When the condition is removed, the AW8738 reactivate itself. When the junction temperature is high, the over-temperature circuit shutdown the device. The circuit switches back to normal operation when the temperature decreases to safe levels. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 22 AW8738 Data Sheet June 2015 V1.1 APPLICATION INFORMATION External Input Resistor-RineGain setting The AW8738 is a differential audio amplifier. The IC integrates two internal input resistors, which is Rini=6.6k. Take external input resistor Rine=3k for an example, gain setting as follows AV 159.5k 159.5k 16.6V/V R ine R ini 3k 6.6k Input Capacitor-Cininput high-pass cutoff frequency The input coupling capacitor blocks the DC voltage at the amplifier input terminal. The input capacitors and input resistors form a high-pass filter with the corner frequency: fH ( 3dB) 1 (Hz) 2 Rintotal Cin Setting the high-pass filter point high can block the 217Hz GSM noise coupled to inputs. Better matching of the input capacitors improves performance of the circuit and also helps to suppress pop-click noise. Take typical application in Figure 1 as an example: f H ( 3dB) 1 1 (Hz) (Hz) 502Hz 2 R intotal Cin 2 9.6k 33nF Differential input filter capacitor Cd (input low-pass cutoff frequency) Input differential input filter capacitor and input resistor together to form a low-pass filter, could be used to attenuate high frequency components of the input signal. When the musical sounds screechy, this low-pass filter can be appropriately attenuate the high frequency part of the input signal, so that the music signal sounds soft and comfortable. -3dB cutoff frequency of the low-pass filter is as follows: f L (3dB) 1 (Hz) 2 (R ini //R ine ) 2 C d With input resistance Rine = 3k, differential capacitance 220pF,for example, the low-pass cutoff frequency is as follows: f L ( 3dB) 1 1 (Hz) (Hz) 175.7kHz 2 (R ini //R ine ) 2 Cd 2 2.06k 2 220 pF Supply Decoupling CapacitorCS The AW8738 is a high-performance audio amplifier that requires adequate power supply decoupling. Place a low equivalent-series-resistance (ESR) ceramic capacitor, typically 0.1F. This choice of capacitor and placement helps with higher frequency transients, spikes, or digital hash on the line. Additionally, placing this decoupling capacitor close to the AW8738 is important, as any parasitic resistance or inductance between the device and the capacitor causes efficiency loss. In addition to the 0.1F ceramic capacitor, place a 10F capacitor on the VBAT supply trace. This larger capacitor acts as www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 23 AW8738 Data Sheet June 2015 V1.1 a charge reservoir, providing energy faster than the board supply, thus helping to prevent any droop in the supply voltage. Flying CapacitorCF The value of the flying capacitor (CF) affects the load regulation and output resistance of the charge pump. A CF value that is too small degrades the devices ability to provide sufficient current drive. Increasing the value of CF improves load regulation and reduces the charge pump output resistance to an extent. A 2.2F@10V capacitor is recommended. Output CapacitorCOUT The output capacitor value and ESR directly affect the ripple at PVDD. Increasing C OUT reduces output ripple. Likewise, decreasing the ESR of COUT reduces both ripple and output resistance. A 4.7F@10V capacitor is recommended. Optional Ferrite Bead Filter The AW8738 passed FCC and CE radiated emissions with no ferrite chip beads and capacitors. Use ferrite chip beads and capacitors if device near the EMI sensitive circuits and/or there are long leads from amplifier to speaker, placed as close as possible to the output pin. In the K class mode, the output is a square wave signal, which causing switch current at the output capacitor, increasing static power consumption, and therefore output capacitor should not be too large, 1nF ceramic capacitors is recommended. Bead VOP 1nF Bead VON 1nF Figure 18 Ferrite Chip Bead and capacitor DEMO PCB Top Layer www.awinic.com.cn Bottom Layer COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 24 AW8738 Data Sheet June 2015 V1.1 DEMO PCB SCHEMATIC PCB AND DEVICE LAYOUT CONSIDERATION In order to obtain excellent performance of AW8738, PCB layout must be carefully considered. The design consideration should follow the following principles: 1. Try to provide a separate short and thick power line to AW8738, the copper width is recommended to be larger than 0.75mm. The decoupling capacitors should be placed as close as possible to power supply pin. 2. The flying capacitors CF1CF2 should be placed as close as possible to C1N, C1P and C2N, C2P, so the same to the output capacitor COUT, it should be close to PVDD pin. The connection from capacitor to PVDD pin should be short and thick. 3. The input capacitors and resistors should be close to AW8738 INN and INP input pin, the input line should be parallel to suppress noise coupling. 4. The beads and capacitor should be placed near to AW8738 VON and VOP pin. The output line from AW8738 to speaker should be as short and thick as possible. The width is recommended to be larger than 0.5mm. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 25 AW8738 Data Sheet June 2015 V1.1 PACKAGE DESCRIPTION TOP VIEW PIN 1# DOT BY MARKING BOTTOM VIEW PIN 1# IDENTIFICATION 0.400 Bsc 2.0000.050 FC-16 (2mmX2mm) 2.0000.050 0.400 Bsc O0.2400.050 1.200 Ref. SIDE VIEW 0.4mm LAND PATTERN 0.203 Ref. A1 B1 C1 D1 A2 B2 C2 D2 A3 B3 C3 D3 A4 B4 C4 D4 0.4mm 0.7500.050 0.4mm 0.4mm 0.000-0.050 O0.23mm 0.4mm FC-16 Unit: mm 0.4mm www.awinic.com.cn 0.4mm 0.4mm 0.4mm 0.4mm COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 26 AW8738 Data Sheet June 2015 V1.1 TAPE&REEL DESCRIPTION Carrier Tape Reel www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 27 AW8738 Data Sheet June 2015 V1.1 VERSION INFORMATION Version Date Description V1.0 2014-05-03 AW8738FCR datasheet V1.0 V1.1 2015-06-16 Add tape & reel description; change C1 to Cd in application diagram; AWINIC Technology cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AWINIC Technologies product. No intellectual property or circuit patent licenses are implied. AWINIC Technology reserves the right to change the circuitry and specifications without notice at any time. www.awinic.com.cn COPYRIGHT (c)2015 SHANGHAI AWINIC TECHNOLOGY CO., LTD. 28