® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier FEATURES GENERAL DESCRIPTION 3.2W Into 3Ω from 5.0V power supply at THD+N = 10% (Typ.). 2.7W Into 4Ω from 5.0V power supply at THD+N = 10% (Typ.). 1.7W Into 8Ω from 5.0V power supply at THD+N = 10% (Typ.) 2.0V~5.5V Power Supply. Low shutdown current (TYP.=0.05uA). Low quiescent current (TYP.=3.0mA). Thermal shutdown protection with auto recovery feature. Advanced power ON/OFF pop reduction. Lead free and green package available. (RoHS Compliant) Space Saving Package -- 8-pin ESOP package. (with thermal pad) The LY8898 is a 3.2W audio power amplifier. It is capable of driving 3Ω speaker load at a continuous average output of 3.2W with less than 10% distortion (THD+N) from a 5.0V power supply and 4Ω speaker load at a continuous average output of 2.7W with less than 10% distortion (THD+N) from a 5.0V power supply. The LY8898 primarily designed for high quality application in other portable communication device. And the LY8898 audio amplifier features low power consumption shutdown mode. It is achieved by driving the shutdown pin with logic high. And the LY8898 has an internal thermal shutdown protection feature. The LY8898 audio amplifier was designed specifically to provide high quality output power with a minimal amount of external components. The LY8898 does not require output capacitors, and the LY8898 is ideally suited for other low voltage applications or portable electronic devices where minimal power consumption is a primary requirement. APPLICATION Boom Box. Education, Toy. MID, Portable electronic devices. Mobile Phones. PIN CONFIGURATION Power ON POP Noise Power OFF POP Noise Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 1 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier PIN DESCRIPTION SYMBOL Pin No. DESCRIPTION ESOP8 SHUTDOWN 1 Shutdown the device. (when HIGH level is shutdown mode) BYPASS 2 Bypass pin +IN 3 Positive Input -IN 4 Negative Input Vo1(-) 5 Negative output VDD 6 Power Supply GND 7 Ground Vo2(+) 8 Positive Output ORDERING INFORMATION Ordering Code Packing Type Speaker Channels Pin/ Package Output Power (THD+N=10%) Input Type Output Type LY8898VT Tape & Reel Mono ESOP8 (with thermal pad) 3.2W/3Ω @5.0V_BTL 2.7W/4Ω @5.0V_BTL 1.7W/8Ω @5.0V_BTL SE/ DF BTL Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 2 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier APPLICATION CIRCUIT Figure 1. LY8898 application schematic with Single –Ended input Figure 2. LY8898 application schematic with Differential input Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 3 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier ABSOLUTE MAXIMUM RATINGS PARAMETER Supply Voltage Operating Temperature Input Voltage Storage Temperature Power Dissipation ESD Susceptibility Junction Temperature Soldering Temperature (under 10 sec) SYMBOL VDD TA VI TSTG PD VESD TJMAX TSOLDER RATING 6.0 -40 to 85 (I grade) -0.3V to VDD +0.3V -65 to 150 Internally Limited 2000 150 260 UNIT V ℃ V ℃ W V ℃ ℃ DC ELECTRICAL CHARACTERISTICS (TA=25℃) *2 SYMBOL TEST CONDITION MIN. TYP. PARAMETER Power supply voltage VDD -2.0 Quiescent Current IQ VDD=5.0V, Load=4Ω. 3.0 Shutdown Current ISD VDD=5.0V, VSD=VDD 0.05 Shutdown Voltage Input High VSDIH VDD=5.0V, VSD Mode = VDD 1.2 Shutdown Voltage Input Low VSDIL VDD=5.0V, VSD Mode = GND Output Offset Voltage VOS VDD=5.0V, Load=4Ω. 7.0 (*2) Typical values are included for reference only and are not guaranteed or tested. Typical values are measured at VCC = VCC(TYP.) and TA = 25℃ MAX. 5.5 9.0 2.0 0.4 50.0 UNIT V mA µA MAX. UNIT V mV OPERATING CHARACTERISTICS(1) (TA=25℃) *2 TEST CONDITION MIN. TYP. Vripple = 200mV 1KHz 64.58 sine p-p, VDD=5.0V, RL=4Ω, Av=2. 217Hz 58.80 Input=GND. Power Supply Rejection Ratio PSRR Vripple = 200mV 1KHz 64.43 sine p-p, VDD=5.0V, RL=4Ω, Av=2. 217Hz 66.0 Input=Floating. A-weight 95.3 VDD=5.0V,RL=4Ω, ing Signal-to-noise ratio SNR Input=GND, Av=2, None 1W=0dB, A-weight 92.1 ing A-weight 34.26 VDD=5.0V,Av=2, ing f=20Hz~20KHz, Output voltage noise Vn None Input=GND, A-weight 50.13 RL=4Ω SPK, ing Shutdown temp. 160 TSD Thermal shutdown temperature Restore temp. 130 (*2) Typical values are included for reference only and are not guaranteed or tested. Typical values are measured at VCC = VCC(TYP.) and TA = 25℃ PARAMETER SYMBOL Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 4 - dB dB uV - ℃ ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier OPERATING CHARACTERISTICS(2) (TA=25℃) SYMBOL TEST CONDITION *2 MIN. TYP. MAX. UNIT 3.8 VDD=5.5V *3 3.2 VDD=5.0V RL=3Ω 1.7 VDD=3.7V THD=10%,f=1 kHz VDD=2.5V 0.72 0.42 VDD=2.0V 2.8 VDD=5.5V *3 2.3 VDD=5.0V RL=3Ω 1.25 VDD=3.7V THD=1%,f=1 kHz VDD=2.5V 0.5 0.25 VDD=2.0V 3.3 VDD=5.5V *3 2.7 VDD=5.0V RL=4Ω 1.5 VDD=3.7V THD=10%,f=1 kHz VDD=2.5V 0.6 0.37 VDD=2.0V Output Power Po W 2.5 VDD=5.5V *3 2.0 VDD=5.0V RL=4Ω 1.1 VDD=3.7V 0.5 THD=1%,f=1 kHz VDD=2.5V 0.25 VDD=2.0V 2.0 VDD=5.5V 1.7 VDD=5.0V RL=8Ω 1.0 VDD=3.7V THD=10%,f=1 kHz VDD=2.5V 0.4 0.25 VDD=2.0V 1.6 VDD=5.5V 1.3 VDD=5.0V RL=8Ω 0.7 VDD=3.7V THD=1%,f=1 kHz VDD=2.5V 0.3 0.2 VDD=2.0V (*2) Typical values are included for reference only and are not guaranteed or tested. Typical values are measured at VCC = VCC(TYP.) and TA = 25℃ (*3) When driving 3Ω or 4Ω loads from 4.2V~5V power supply, the device must be mounted to a circuit board. PARAMETER Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 5 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier TYPICAL PERFORMANCE CHARACTERISTICS Figure 3 THD+N vs. Output Power (@ RL=3Ω, f=1kHz, AV=10) Figure 4 THD+N vs. Output Power (@ RL=4Ω, f=1kHz, AV=10) Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 6 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier Figure 5 THD+N vs. Output Power (@ RL=8Ω, f=1kHz, AV=10) Figure 6 Power Supply Rejection Ratio (PSRR) Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 7 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier Figure 7 Frequency response vs. input capacitor values Figure 8 SNR vs. Noise Level Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 8 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier SD Current vs. SD Voltage Quiescent Current vs. Supply voltage QUIESCENT CURRENT vs. SUPPLY VOLTAGE SHUTDOWN CURRENT vs SHUTDOWN VOLTAGE 6 1 I(Q) - Quiescent Current - m A 3.7V 0.8 I(SD) Shutdown Current - uA No Load 8Ω 4Ω 3Ω 2.5v 0.9 5v 0.7 0.6 0.5 0.4 0.3 0.2 5 4 3 2 0.1 1 0 0 0.1 0.2 0.3 0.4 0.5 Shutdown Voltage - V 0.6 2 0.7 2.5 3 3.7 4.2 5 5.5 6 VDD - Supply Voltage(V) Load Resistance vs. Output Power (THD+N=10%) Load Resistance vs. Output Power (THD+N=1%) Output Power vs Load Resistance Output Power vs Load Resistance 4 3 2.5V 2.5V 3.7V 5V 2.5 4.2V 4.2V 2 5.5V 2 3.7V 2.5 5V 3 P o -O u t p u t P o w e r P o -O u t p u t P o w e r 3.5 1.5 5.5V 1.5 1 1 0.5 0.5 0 0 3Ω 4Ω 8Ω 12Ω 16Ω 20Ω 24Ω 28Ω 3Ω 32Ω 4Ω 8Ω 12Ω Load Resistance 2.5V 32Ω 2.0V 2.5V 800 3.7V 3.7V 700 5.0V 700 Supply Current-m A Supply Current-m A 28Ω SUPPLY CURRENT vs. OUTPUT POWER(RL=4Ω) 900 2.0V 800 24Ω VDD Current vs. Output Power (RL=4Ω) SUPPLY CURRENT vs. OUTPUT POWER(RL=3Ω) 900 20Ω Load Resistance VDD Current vs. Output Power (RL=3Ω) 1000 16Ω 600 500 400 300 5.0V 600 500 400 300 200 200 100 100 0 0 0 0.2 0.4 0.8 1 1.2 1.8 2.2 2.4 2.6 2.8 3 3.2 0 3.4 0.2 0.4 0.8 1 1.2 1.8 2.2 2.4 Po-Output Power-W(RL=4Ω) Po-Output Power-W(RL=3Ω) Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 9 2.6 2.8 3 3.2 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier VDD Current vs. Output Power (RL=8Ω) VDD vs. Output Power (RL=3Ω) OUTPUT POWER vs. SUPPLY VOLTAGE(3Ω) SUPPLY CURRENT vs. OUTPUT POWER(RL=4Ω) 500 4 THD+N=10% 2.0V 450 3.5 2.5V THD+N=1% 3.7V 400 3 5.0V 300 Po-Output Power Supply Current-mA 350 250 200 150 100 2.5 2 1.5 1 0.5 50 0 2.0V 0 0 0.2 0.4 0.8 1 1.2 1.8 Po-Output Power-W(RL=4Ω) VDD vs. Output Power (RL=4Ω) 3 5V 5.5V VDD vs. Output Power (RL=8Ω) OUTPUT POWER vs. SUPPLY VOLTAGE((8Ω) OUTPUT POWER vs. SUPPLY VOLTAGE(4Ω) 3.5 2.5V 3.7V 4.2V VDD-Supply Voltage-V 2.5 THD+N=10% THD+N=1% 2 THD+N=10% THD+N=1% Po-Output Power Po-Output Power 2.5 2 1.5 1 0.5 0 2.0V 2.5V 3.7V 4.2V 5V VDD-Supply Voltage-V 5.5V 1.5 1 0.5 0 2.0V 2.5V 3.7V 4.2V 5V VDD-Supply Voltage-V Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 10 5.5V ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier Output power vs. Temperature Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 11 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier APPLICATION INFORMATION Bridged configuration explanation As shown in Figure 1 and 2, the LY8898 has two operational amplifiers internally, allowing for a few different amplifier configurations. The first amplifier’s gain is externally configurable, while the second amplifier is internally fixed in a unity-gain, inverting configuration. The closed-loop gain of the first amplifier is set by selecting the ratio of Rf to RIN while the second amplifier’s gain is fixed by the two internal 20kΩ resistors. Figure 1 and 2 shows that the output of amplifier one serves as the input to amplifier two which results in both amplifiers producing signals identical in magnitude, but out of phase by 180°. Consequently, the differential gain for the IC is AVD= 2 X ( Rf / RIN ) ………………………………………………………………(1) By driving the load differentially through outputs Vo1(-) and Vo2(+), an amplifier configuration commonly referred to as “bridged mode” is established. Bridged mode operation is different from the classical single-ended amplifier configuration where one side of the load is connected to ground. A bridge amplifier design has a few distinct advantages over the single-ended configuration, as it provides differential drive to the load, thus doubling output swing for a specified supply voltage. Four times the output power is possible as compared to a single-ended amplifier under the same conditions. This increase in attainable output power assumes that the amplifier is not current limited or clipped. In order to choose an amplifier’s closed-loop gain without causing excessive clipping, please refer to the Audio Power Amplifier Design section. A bridge configuration, such as the one used in the LY8898, also creates a second advantage over single -ended amplifiers. Since the differential outputs, Vo1(-) and Vo2(+), are biased at half-supply, no net DC voltage exists across the load. This eliminates the need for an output coupling capacitor which is required in a single supply, single-ended amplifier configuration. Without an output coupling capacitor, the half-supply bias across the load would result in both increased internal IC power dissipation and also possible loudspeaker damage. Input Capacitors (Ci) The LY8898 input capacitors and input resistors form a high-pass filter with the corner frequency, fc, determined in equation Equation 2. 1 fc = ----------------………………………………………………………………(2) 2πRiCi Equation 3 is reconfigured to solve for the input coupling capacitance. 1 Ci = -----------------…………………………………………………………….(3) 2πRifc For example In the table 1 shows the external components. Rin in connect with Cin to create a high-pass filter. Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 12 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier Reference Ri Ci corner frequency Table 1. Typical Component Values Description Note 20KΩ 1% tolerance resistors 0.1uF 0.22uF 0.33uF 0.47uF 80%/–20% non polarized 79.57Hz 36.17Hz 20.4Hz 16.93Hz Ci = 1 / ( 2πRifc) Ci = 1 / ( 2π x20KΩ x20Hz)=0.1uF,One would likely choose a value of 0.1uF as this value is commonly used. Note that it is important to Ci must be 10 times smaller than the bypass capacitor to reduce clicking and popping noise from power on/off and entering and leaving shutdown. After sizing Ci for a given cutoff frequency, size the bypass capacitor to 10 times that of the input capacitor. Ci ≦ Cbypass / 10 Bypass Capacitor Value Selection Besides minimizing the input capacitor size, careful consideration should be paid to value of Cbypass, the capacitor connected to the BYPASS pin. Since Cbypass determines how fast the LY8898 settles to quiescent operation, its value is critical when minimizing turn-on pops. The slower the LY8898’s outputs ramp to their quiescent DC voltage (nominally 1/2 VDD), the smaller the turn-on pop. Choosing Cbypass value equal 1.0 to 10 uF along with a small value of Ci (in the range of 1 nF to 0.39 μF), produces a click-less and pop-less shutdown function. As discussed above, choosing Ci no larger than necessary for the desired bandwith helps minimize clicks and pops. Therefore, increasing the bypass capacitor reduces clicking and popping noise from power on/off and entering and leaving shutdown. To have minimal pop, Cbypass should be 10 times larger than Ci. Cbypass ≧ Ci x 10 PARAMETER Start-up time from shutdown Table 2. CBYPASS Reference Component Values SYMBOL TEST CONDITION MIN. TYP. 940 Cbypass = 10μf VDD=5.0V, Cbypass = 4.7μf 550 Ci=0.1uF, Ri=20KΩ, Cbypass = 2.2μf 190 Av=10 Cbypass = 1.0μf 158 ZI 780 Cbypass = 10μf VDD=3.7V, Cbypass = 4.7μf 480 Ci=0.1uF, Ri=20KΩ, Cbypass = 2.2μf 180 Av=10 Cbypass = 1.0μf 126 MAX. - UNIT ms Power Supply Bypassing Capacitor As with any amplifier, proper supply bypassing is critical for low noise performance and high power supply rejection. The capacitor location on both the bypass and power supply pins should be as close to the device as possible. The LY8898 is a mono class AB audio amplifier that requires adequate power supply decoupling to ensure the efficiency is high and total harmonic distortion (THD) is low. For higher frequency transients, spikes, or digital hash on the line, a good low equivalent-series-resistance ceramic capacitor or electrolytic capacitors, typically 10~220uF, placed as close as possible to the device VDD lead works best. Placing 0.1uF decoupling capacitor close to the LY8898 is very important for the efficiency of the class AB amplifier, because any Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 13 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier resistance or inductance in the trace between the device and the capacitor can cause a loss in efficiency and protect device damage. For filtering lower-frequency noise signals, a 10.0uF or greater capacitor placed near the audio power amplifier would also help, but it is not required in most applications because of the high PSRR of this device. Shutdown Function When the LY8898 not in use. The device will be to turn off the amplifier to reduce power consumption. When logic high is applied to the shutdown pin, this shutdown feature will turns the amplifier off. By switching the shutdown pin connected to VDD, the device supply current draw will be minimized in idle mode. The pin cannot be left floating due to the internal did not pull-up. Over-Heat Protection The LY8898 has a built-in over-heat protection circuit , it will turn off all power output when the chip temperature over 160℃, the chip will return to normal operation automatically after the temperature cool down to 130℃. PCB LAYOUT All the external components must place very close to the LY8898. The input resistors need to be very close to the LY8898 input pins so noise does not couple on the high impedance nodes between the input resistors and the input amplifier of the LY8898. Then place the decoupling capacitor Cs, close to the LY8898 is important for the efficiency of the class AB amplifier. Any resistance or inductance in the trace between the device and the capacitor can cause a loss in efficiency. Making the high current traces going to VDD, GND, VO+ and VO- pins of the LY8898 should be as wide as possible to minimize trace resistance. If these traces are too thin, the LY8898's performance and output power will decrease. The input traces do not need to be wide, but do need to run side-by-side to enable common-mode noise cancellation. Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 14 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier DEMO BOARD INFORMATION Demo Board Application Circuit : Figure 9. LY8898 Demo Board Application Circuit Demo Board BOM List : LY8898 V2.0 BOM List (Stereo Mode) No. Description 1 Resistor, 20KΩ 2 Resistor, 100KΩ 3 Capacitor, 0.1uF 4 Capacitor, 1.0uF Reference R1, R4B (R2,R3 DF input only) R5 C1, C4 (C2 DF input only) C3 5 6 7 Capacitor, 10.0uF IC 1*2 Pin Header C5 U1 J1 Note 1/16W,1% 1/16W,1% 80%/−20%, non polarized 80%/−20%, non polarized 25V,105℃,8x11,EC Cap. LY8898 (ESOP8) Pitch 2.54 mm Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 15 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier Demo Board Artwork : Top Silkscreen Top Layer Composite view Bottom Layer (*3) When driving 3Ω or 4Ω loads from 4.2V~5V power supply, the device must be mounted to a circuit board. Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 16 ® LY8898 Rev. 1.2 3.2 Watt Audio Power Amplifier PACKAGE OUTLINE DIMENSION 8 Pin ESOP Package Outline Dimension Lyontek Inc. reserves the rights to change the specifications and products without notice. 5F, No. 2, lndustry E . Rd. IX, Science-Based Industrial Park, Hsinchu 300, Taiwan TEL: 886-3-6668838 FAX: 886-3-6668836 17