® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 FEATURES GENERAL DESCRIPTION 2.0V~5.5V Power supply. Thermal shutdown Protection. Low current shutdown mode No output capacitors and networks or bootstrap capacitors required Low noise during turn-on and turn-off transitions Lead free and green package available. (RoHS Compliant) Space Saving Package -- 8-pin MSOP package. -- 8-pin DFN Package The LY8891 is a 2.0W audio power amplifier. It is capable of driving 4Ω speaker load at a continuous average output of 2.0W with less than 10% distortion (THD+N) from a 5.5V power supply and 8Ω speaker load at a continuous average output of 1.4W with less than 10% distortion (THD+N) from a 5.0V power supply. The LY8891 primarily designed for high quality application in other portable communication device. And the LY8891 audio amplifier features low power consumption shutdown mode. It is achieved by driving the shutdown pin with logic low. And the LY8891 has an internal thermal shutdown protection feature. The LY8891 audio amplifier was designed specifically to provide high quality output power with a minimal amount of external components. The LY8891 does not require output capacitors, and the LY8891 is ideally suited for other low voltage applications or portable electronic devices where minimal power consumption is a primary requirement. APPLICATION Portable electronic devices Mobile Phones PDAs PIN CONFIGURATION 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 PIN DESCRIPTION Pin No. SYMBOL DESCRIPTION MSOP8 DFN8 SHUTDOWN 1 1 Shutdown the device. (when LOW level is shutdown mode) BYPASS 2 2 Bypass pin +IN 3 3 Positive Input -IN 4 4 Negative Input Vo1 5 5 Negative output VDD 6 6 Power Supply GND 7 7 Ground Vo2 8 8 Positive Output ORDERING INFORMATION Ordering Code Speaker Channels Pin/ Package Output Power (THD+N=10%) Input Type Output Type LY8891UL Mono MSOP8 1.7W/8Ω @5.5V_BTL 1.4W/8Ω @5.0V_BTL SE/ DF BTL DFN8 2.0W/4Ω @5.5V_BTL 1.8W/4Ω @5.0V_BTL 1.7W/8Ω @5.5V_BTL 1.4W/8Ω @5.0V_BTL SE/ DF BTL LY8891BL Mono 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 APPLICATION CIRCUIT Figure 1. LY8891 application schematic with Single –Ended input Figure 2. LY8891 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 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 (VDD=5.0V, TA=25℃) PARAMETER Power Supply Current Shutdown Current Shutdown Voltage Input High Shutdown Voltage Input Low Output Offset Voltage Resistor Output to GND Output Power Total Harmonic Distortion+ Noise SYMBOL IDD ISD VSDIH VSDIL VOS ROUT-GND TEST CONDITION VIN = 0V, IO = 0A, 8Ω Load VSHUTDOWN = 0V VSD Mode = VDD VSD Mode = GND THD = 10% , f = 1 kHz RL=4Ω (at 5.5V) THD = 10% , f = 1 kHz RL=4Ω (at 5.0V) THD = 1% , f = 1 kHz RL=4Ω (at 5.0V) Po THD = 10% , f = 1 kHz RL=8Ω (at 5.5V) THD = 10% , f = 1 kHz RL=8Ω (at 5.0V) THD = 1% , f = 1 kHz RL=8Ω (at 5.0V) THD+N Po = 635 mWrms; f = 1kHz MIN. 1.2 - TYP. 5.0 0.1 7.0 9.5 *1 - 2.0 - - 1.8 - - 1.4 - - 1.7 - - 1.4 - - 1.0 - UNIT mA µA V mV kΩ W 0.1 66 (f = Vripple = 200mV sine p-p, 217Hz) Power Supply Rejection Ratio PSRR 66 (f = Input with floating. 1kHz) Wake-up time TWU Bypass Cap.=1.0uF, 5.0V 145 TSD Thermal Shutdown Temperature 150 170 Shut Down Time TSDT 8 Ω load 1.0 (*1)Typical values are included for reference only and are not guaranteed or tested. Typical values are measured at VCC = VCC(TYP.) and TA = 25℃ - 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 MAX. 15.0 2.0 0.4 50.0 - % - dB 190 ms ℃ ms ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 DC ELECTRICAL CHARACTERISTICS (VDD=3.6V, TA=25℃) PARAMETER Power Supply Current Shutdown Current Shutdown Voltage Input High Shutdown Voltage Input Low Output Offset Voltage Resistor Output to GND Output Power Total Harmonic Distortion+ Noise SYMBOL IDD ISD VSDIH VSDIL VOS ROUT-GND TEST CONDITION VIN = 0V, IO = 0A, 8Ω Load VSHUTDOWN = = 0V VSD Mode = VDD VSD Mode = GND THD = 10% , f = 1 kHz RL=4Ω THD = 1% , f = 1 kHz RL=4Ω Po THD = 10% , f = 1 kHz RL=8Ω THD = 1% , f = 1 kHz RL=8Ω THD+N Po = 280 mWrms , f = 1kHz MIN. 1.2 7.0 TYP. 4.5 0.1 7.0 8.5 *1 - 900 - - 700 - - 700 - - 550 - UNIT mA µA V mV kΩ mW 0.11 62 (f = Vripple = 200mV sine p-p, 217Hz) Power Supply Rejection Ratio PSRR 62 (f = Input with floating. 1kHz) Wake-up time TWU 82 TSD Thermal Shutdown Temperature 150 170 (*1)Typical values are included for reference only and are not guaranteed or tested. Typical values are measured at VCC = VCC(TYP.) and TA = 25℃ - 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 MAX. 14.0 2.0 0.4 50.0 9.7 - % - dB 190 ms ℃ ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 TYPICAL PERFORMANCE CHARACTERISTICS Figure 3 THD+N vs Frequency (at RL=8Ω, AV=2) Figure 4 THD+N vs Frequency (at RL=4Ω, AV=2) 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 Figure 5 THD+N vs Power Out (@ RL=8Ω, f=1kHz, AV=2) Figure 6 THD+N vs Power Out (@ RL=4Ω, f=1kHz, AV=2) 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 Figure 7 Power Supply Rejection Ratio (PSRR) (@ RL=8Ω, Av=2, Vripple = 200mVp-p, RIN = Floating) 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 APPLICATION INFORMATION BRIDGED CONFIGURATION EXPLANATION As shown in Figure 1, the LY8891 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 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 LY8891, 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 LY8891 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. Table 1. Typical Component Values Reference Description Note Ri 20KΩ 1% tolerance resistors Ci 0.39uF 80%/–20% 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 Ci = 1 / ( 2πRifc) Ci = 1 / ( 2π x20KΩ x20Hz)=0.397uF，Use 0.39uF POWER SUPPLY BYPASSING 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. 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 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 PACKAGE OUTLINE DIMENSION 8 Pin MSOP 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 11 ® LY8891 2.0 Watt Audio Power Amplifier Rev. 1.7 PACKAGE OUTLINE DIMENSION (Continued) 8-Pin DFN 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 12