3W Mono Filterless Class-D Audio Power Amplifier BA16852 Data Sheet Rev.1.1, 2007.08.28 Biforst Technology Inc. BA16852 3W Mono Filterless Class-D Audio Power Amplifier 3W Mono Filterless Class-D Audio Power Amplifier BA16852 GENERAL DESCRIPTION The BA16852 is a cost-effective mono class-d audio power amplifier that assembles in 1.45mm x 1.45mm wafer chip scale package (CSP). Only three external components offer space and cost saving for cellular phone or PDA application. The BA16852 provides 3W high performance output capacity at 4-Ω load. Other feature like 90% efficiency, -75dB PSRR, fully differential design reduces RF rectification, and allows independent gain while summing signals from various audio sources. BA16852 also integrates Anti-Pop, Output Short & Over-Heat Protection Circuitry to increase device reliability. The functionality makes this device ideal for cellular phone, PDA, and other applications that demand more battery life. FEATURE Wide Operation Voltage From 2.5 To 5.5V Efficiency with 8-Ω Speaker 89% at 1.3W 80% at 0.25W Output Driver Capability, 1.3W With 8-Ω Load And THD+N < 1% Output Driver Capability, 2.3W With 4-Ω Load And THD+N < 1% Low 1μA Shutdown Current Low 5mA Typical Quiescent Current PSRR, -75dB, No Need For Voltage Regulator Internally Generated 250KHz Switching Frequency Without External Capacitor And Resistor External Gain Configuration Capability Fully Differential Design For Eliminates Two Input Coupling Capacitors And Reduces RF Rectification Filterless PWM Output Technology without LC Output Filter Integrated Anti-Pop Circuitry Integrated Output Short Protection Circuitry Integrated Over-Heat Protection Circuitry Package Type : MSOP 8Pin APPLICATION Cellular Phones PDA and Smart Phones Portable Electronic Device Portable Computer _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 2 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier APPLICATION CIRCUIT - RI Internal Osciliator To Power Source VDD CS INN OUTN Audio Input PWM + + RI SD_B Driver OUTP INP Bias Circuitry GND BA16852 Figure 1. Typical BA16852 Application Circuit PIN ASSIGNMENT MSOP 8Pin Top View SD_B NC INP INN 1 2 3 4 8 7 6 5 OUTN GND VDD OUTP _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 3 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier PIN LIST & DESCRIPTION Pin No. Pin 1 SD_B 2 NC 3 I/O Pad Function Type Input Shutdown (Active Low Logic) INP Input Positive differential audio input 4 INN Input Negative differential audio input 5 OUTP Output Positive BTL output 6 VDD Power Power supply 7 GND Power Power ground 8 OUTN Output Negative BTL output Function Block Diagram VDD 150KΩ INP + + - + + - + Data Processor INN Output Driver OUTN + - 150KΩ SD_B OUTP Shutdown Control 300KΩ Bias & References Clock Generator Startup Protection OC Detect GND _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 4 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier These device have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. ABSOLUTE MAXIMUM RATINGS SYMBOL VDD VI TA TJ TSTG PARAMETER Supply Voltage Range Input Voltage Range Operating Free-Air Temperature Range Operating Junction Temperature Range Storage Temperature Range VALUE -0.3V to 6V -0.3V to VDD+0.3V -40oC to 85oC -40oC to 125oC -65oC to 150oC RECOMMANDED OPERATING CONDITIONS SYMBOL VDD VIH VIL RI fPWM VIC TA PARAMETER Supply Voltage High-Level Input Voltage SHUTDOWN_B Low-Level Input Voltage SHUTDOWN_B Input Resistor GAIN ≤ 20V/V PWM Frequency Common Mode Input Voltage Range VDD=2.5V, 5.5V, CMRR ≤ -49dB Operating Free-Air Temperature MIN 2.5 2 0 15 200 0.5 -40 MAX 5.5 VDD 0.8 300 VDD-0.8 85 UNIT V V V kΩ KHz V o C ELECTRICAL CHARACTERISTICS TA = 25oC (unless otherwise noted) SYMBOL PSRR CMRR | IIH | | IIL | PARAMETER Output Offset Voltage (Measured Differentially) Power Supply Rejection Ratio Common Mode Rejection Ratio High-Level Input Current Low-Level Input Current I(Q) Quiescent Current I(SD) Shutdown Current rDS(ON) Static Drain-Source On-State Resistance | VOS | F(SW) TEST CONDITIONS TYP MAX UNIT VI = 0V, AV = 2V/V, VDD = 2.5 to 5.5V 1 25 mV VDD = 2.5 to 5.5V VDD = 2.5 to 5.5V, VIC = 0.5V to VDD-0.8V VDD = 5.5V, VI = 5.8V VDD = 5.5V, VI = -0.3V VDD = 5.5V, no load VDD = 3.6V, no load VDD = 2.5V, no load V(SHUTDOWN_B) = 0.35V, VDD = 2.5 to 5.5V -75 -68 dB 5.8 4.3 3.1 0.5 -55 -49 100 5 6.2 4.7 3.4 2 450 650 μA μA mA μA High Side VDD = 5V, IO = 500mA mΩ Low Side Switching Frequency VDD = 2.5 to 5.5V Gain VDD = 2.5 to 5.5V Resistance from shutdown to GND MIN 200 250 300 285kΩ 300kΩ 350kΩ RI RI RI 300 kHz V V kΩ _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 5 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier OPWEATING CHARACTERISTICS TA = 25oC , Gain = 2V/V, RL = 3 / 4 / 8Ω (unless otherwise noted) SYMBOL PARAMETER TEST CONDITIONS THD+N = 10%, f = 1KHz, RL = 3Ω THD+N = 1%, f = 1KHz, RL = 3Ω THD+N = 10%, f = 1KHz, RL = 4Ω PO Output Power THD+N = 1%, f = 1KHz, RL = 4Ω THD+N = 10%, f = 1KHz, RL = 8Ω THD+N = 1%, f = 1KHz, RL = 8Ω THD+N Total Harmonic Distortion Plus Noise SNR Supply Ripple Rejection Ration Signal-to-noise Ratio Vn Output Voltage Noise KSVR CMRR ZI Common Mode Rejection Ratio Input Impedance Start-up time from shutdown MIN VDD = 5V VDD = 3.6V VDD = 2.5V VDD = 5V VDD = 3.6V VDD = 2.5V VDD = 5V VDD = 3.6V VDD = 2.5V VDD = 5V VDD = 3.6V VDD = 2.5V VDD = 5V VDD = 3.6V VDD = 2.5V VDD = 5V VDD = 3.6V VDD = 2.5V f = 217Hz W W W W -67 dB 93 88 63 dB μVRMS dB -63 141 VDD = 3.6V MAX UNIT 3.6 1.8 0.7 2.8 1.3 0.56 3 1.5 0.66 2.3 1.1 0.48 1.7 0.89 0.4 1.33 0.65 0.3 0.18% 0.16% 0.27% VDD = 5V, PO = 1W, RL = 8Ω, f = 1KHz VDD = 3.6V, PO = 0.5W, RL = 8Ω, f = 1KHz VDD = 3.0V, PO = 0.2W, RL = 8Ω, f = 1KHz VDD = 3.6V, Input AC-Grounded with f = 215Hz, Ci = 2μF V(RIPPLE) = 0.2VPP VDD = 5V, PO = 1W, RL = 8Ω No Weight VDD = 3.6V, f = 20Hz to 20KHz, Input AC-Grounded with Ci = 2μF A Weight VDD = 3.6V, VIC = 1VPP TYP 150 30 159 kΩ ms _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 6 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier TYPICAL CHARACTERISTIC Table of Graphs Test Item Figure Efficiency vs. Output Power at 8Ω Load Efficiency vs. Output Power at 4Ω Load Power Dissipation vs. Output Power at 5.0V PD Power Dissipation vs. Output Power at 3.6V Supply Current vs. Output Power at 8Ω Load Supply Current vs. Output Power at 4Ω Load I(Q) Quiescent Current vs. Supply Voltage I(SD) Shutdown Current vs. Shutdown Voltage Output Power at 1% THD+N vs. Load Resistance PO Output Power at 10% THD+N vs. Load Resistance Output Power vs. Supply Voltage Total Harmonic Distortion + Noise vs. Output Power at 8Ω Load Total Harmonic Distortion + Noise vs. Output Power at 4Ω Load Total Harmonic Distortion + Noise vs. Output Power at 3Ω Load Total Harmonic Distortion + Noise vs. Frequency at 5.0V & 8Ω Load Total Harmonic Distortion + Noise vs. Frequency at 3.6V & 8Ω Load THD+N Total Harmonic Distortion + Noise vs. Frequency at 2.5V & 8Ω Load Total Harmonic Distortion + Noise vs. Frequency at 5/4/3.6/3/2.5V, 250mW Output, 8Ω Load Total Harmonic Distortion + Noise vs. Frequency at 5.0V & 4Ω Load Total Harmonic Distortion + Noise vs. Frequency at 3.6V & 4Ω Load Total Harmonic Distortion + Noise vs. Frequency at 2.5V & 4Ω Load Total Harmonic Distortion + Noise vs. Frequency at 5/4/3.6/3/2.5V, 250mW Output, 4Ω Load Supply Ripple Rejection Ratio vs. Frequency at 8Ω Load KSVR Supply Ripple Rejection Ratio vs. Frequency at 4Ω Load Supply Ripple Rejection Ratio vs. Frequency at Input Floating 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Test Set-Up For Graphs + AP (Analog Generator) - CI RI CI RI INP INN OUTP BA16852 OUTN + Load AP AUX-0025 AP - (Analog Analyzer) 1μF VDD Notes: 1. CI was shorted for any Common-Mode input voltage measurement. 2. A 22μH inductor was placed in series with the load resistor to emulate a small speaker for efficiency measurement. 3. The AP AUX-0025 low-pass filter is required. 4. The 22-KHz or 30-KHz low-pass filter is required even if the AP analyzer has an internal low-pass filter. _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 7 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 2. Efficiency vs. Output Power at 8Ω Load Figure 3. Efficiency vs. Output Power at 4Ω Load Figure 4. Power Dissipation vs. Output Power at 5.0V _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 8 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 5. Power Dissipation vs. Output Power at 3.6V Figure 6. Supply Current vs. Output Power at 8Ω Load Figure 7. Supply Current vs. Output Power at 4Ω Load _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 9 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 8. Quiescent Current vs. Supply Voltage Figure 9. Shutdown Current vs. Shutdown Voltage Figure 10. Output Power at 1% THD+N vs. Load Resistance _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 10 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 11. Output Power at 10% THD+N vs. Load Resistance Figure 12. Output Power vs. Supply Voltage Figure 13. Total Harmonic Distortion + Noise vs. Supply Voltage at 8Ω Load _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 11 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 14. Total Harmonic Distortion + Noise vs. Supply Voltage at 4Ω Load Figure 15. Total Harmonic Distortion + Noise vs. Supply Voltage at 3Ω Load Figure 16. Total Harmonic Distortion + Noise vs. Frequency at 5.0V & 8Ω Load _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 12 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 17. Total Harmonic Distortion + Noise vs. Frequency at 3.6V & 8Ω Load Figure 18. Total Harmonic Distortion + Noise vs. Frequency at 2.5V & 8Ω Load Figure 19. Total Harmonic Distortion + Noise vs. Frequency at 5/4/3.6/3/2.5V, 250mW Output, 8Ω Load _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 13 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 20. Total Harmonic Distortion + Noise vs. Frequency at 5.0V & 4Ω Load Figure 21. Total Harmonic Distortion + Noise vs. Frequency at 3.6V & 4Ω Load Figure 22. Total Harmonic Distortion + Noise vs. Frequency at 2.5V & 4Ω Load _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 14 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 23. Total Harmonic Distortion + Noise vs. Frequency at 5/4/3.6/3/2.5V, 250mW Output, 4Ω Load Figure 24. Supply Ripple Rejection Ration vs. Frequency at 8Ω Load Figure 25. Supply Ripple Rejection Ration vs. Frequency at 4Ω Load _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 15 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Figure 26. Supply Ripple Rejection Ration vs. Frequency at Input Floating _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 16 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Function Description The basic structure of BA16852 is a differential amplifier with differential inputs and outputs. The BA16852 has one differential amplifier and one common-mode amplifier inside. The differential amplifier output a differential voltage that is equal to the differential input times the gain. The common-mode feedback ensures that the common-mode voltage at the output is biased around VDD/2 regardless of the common-mode voltage at the input. The BA16852 can still be used with a single ended input. The BA16852 should be used with differential inputs when in a noisy environment, like a wireless handset, to ensure maximum noise rejection. Input Resistors (RI) The gain of BA16852 is set by external resistors RI show in Figure 1. Set the gain of the amplifier according to Equation (1) 2× 150kΩ V Gain = ( ) (1) V RI The gain should be set to 2 V/V or lower for best performance. Lower gain allows the BA16852 use a high voltage at input and make the input less susceptible to noise. Resistor matching is very important in fully differential amplifiers. The balance of the output on the reference voltage depends on matched ratios of the resistors. It is recommended to use 1% tolerance resistor or better for best performance. Matching is more important than overall tolerance. Resistor arrays with 1% matching can be used with a tolerance greater than 1%. The RI resistor should be placed close to the BA16852 and keep the input traces close to each other with the same length in high noise environment. It can limit noise injection on the high-impedance nodes. Power Supply Decoupling Capacitor (CS) As with any power amplifier, proper power supply decoupling capacitor is critical for low noise performance and high power supply rejection ration (PSRR). A good low equivalent-series-resistance (ESR) ceramic capacitor, typically 1μF, placed as close as possible to the device VDD lead works best. Placing this decoupling capacitor close to the BA16852 is very important for the efficiency of the class-d amplifier, because any resistance or inductance in the trace between the device and capacitor can cause a loss in efficiency. Input Capacitor (CI) The input capacitor may be needed for some applications or when the source is single-ended (See Figure 28). This capacitor can block the DC voltage at the amplifier input terminal and create a high-pass filter with the input resistor RI. The cut-off frequency of high-pass filter is according to Equation (2) 1 (Hz) (2) fC = 2π × R I × C I _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 17 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier The value of the input capacitor affects the low frequency performance of the circuit directly. Speakers in wireless phone can’t respond well to low frequency, so the cut-off frequency can be set to block low frequency in this application. For example, power supply noise is at 217Hz in a GSM phone. Setting cut-off frequency of high-pass filter above 217Hz can filter out this noise that it is not amplified and heard on the output. Capacitor has 10% tolerance or better is recommended for impedance matching. Differential Circuit Configurations The BA16852 can be used in many different circuit configurations. The simplest and best performing is the DC coupled, differential input configuration show in Figure 27. The resistor RI can set the amplifier output gain. Set the gain of the amplifier according to Equation (1). The input capacitors can be used in a differential configure as show in Figure 28. The input capacitor CI with input resistor RI can create a high-pass filter. The cut-off frequency of high-pass filter is according to Equation (2). Equation (1) above is used to determine the value of the RI resistors for a desired gain. The BA16852 can be used to amplify more than one audio source. Figure 29 shows a dual differential input configuration. The gain for each input source can be set independently according to Equation (3) and (4). 2× 150kΩ V ( ) (3) Gain 1 = V R I1 Gain 2 = 2 × 150kΩ V ( ) R I2 V (4) The input capacitors can be used with one or more input source as well to have different frequency responses depending on the source or if a DC voltage needs to be blocked from the source. Differential Input Internal Osciliator RI To Power Source VDD CS INN OUTN + RI PWM Driver OUTP INP SD_B Bias Circuitry GND BA16852 Shutdown Control Figure 27. Differential Input Configuration _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 18 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Differential Input CI RI Internal Osciliator VDD To Power Source CS INN OUTN + CI RI PWM Driver OUTP INP Bias Circuitry SD_B GND BA16852 Shutdown Control Figure 28. Differential Input Configuration with Input Capacitors Differential Input 1 RI1 RI1 Differential Input 2 Internal Osciliator RI2 VDD To Power Source CS INN OUTN + RI2 PWM Driver OUTP INP SD_B Bias Circuitry GND BA16852 Shutdown Control Figure 29. Dual Differential Input Configuration Single-Ended Circuit Configurations The BA16852 can also be used with single-ended sources, but input capacitors will be needed to block any DC at the input terminals. The typical single-ended application configuration shows in Figure 30. The equation of gain is Equation (1) and the equation of frequency response is Equation (2), hold for the single-ended configuration as shown in Figure 30. When using more than one single-ended source as shown in Figure 31. The gain and cut-off frequency (fC1 and fC2) for each input source can be set independently, shows in Equation (5) ~ Equation (8). Resistor, RI3, and capacitor, CI3, are needed on the INP terminal to match the impedance on the INN terminal. Equation (9) and Equation (10) shows how to calculate CI3 and RI3 value. The single-ended inputs must be driven by low impedance source even if one of the inputs is not outputting an ac signal. _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 19 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Gain 1 = 2× 150kΩ V ( ) V R I1 (5) Gain 2 = 2 × 150kΩ V ( ) R I2 V (6) fC1 = 1 (Hz) 2π × R I1 × C I1 (7) fC2 = 1 (Hz) 2π × R I2 × C I2 (8) C I3 = C I1 + C I2 R I3 = (9) 1 R × R I2 = I1 1 1 + ( ) R I1 + R I2 R I1 R I2 Single-Ended Input CI RI (10) Internal Osciliator To Power Source VDD CS INN OUTN + CI RI PWM Driver OUTP INP Bias Circuitry SD_B GND BA16852 Shutdown Control Figure 30. Single-Ended Input Configuration Single-Ended Input 1 Single-Ended Input 2 CI1 CI2 RI1 RI2 Internal Osciliator VDD To Power Source CS INN OUTN CI3 + RI3 SD_B PWM Driver OUTP INP Bias Circuitry GND BA16852 Shutdown Control Figure 31. Dual Single-Ended Input Configuration _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 20 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Combine Single-Ended & Differential Circuit Configurations A typical application with one single-ended source and one differential source shows in Figure 32. Ground noise can couple in through INP terminal with this method. It is better to use dual differential inputs. The cut-off frequency of the single-ended input is set by CI shows in Equation (13). To assure that each input is balanced, the single-ended input must be driven by a low-impedance source even if the input is not in use. 2 × 150kΩ V ( ) (11) Gain 1 = V R I1 Gain 2 = fC2 = 2 × 150kΩ V ( ) R I2 V (12) 1 (Hz) 2π × R I2 × C I (13) Differential Input 1 RI1 RI1 Single-Ended Input 2 CI Internal Osciliator RI2 VDD To Power Source CS INN OUTN CI + RI2 PWM Driver OUTP INP SD_B Bias Circuitry GND BA16852 Shutdown Control Figure 32. Dual Input with a Single-Ended Input and a Differential Input Configuration Shutdown Mode The BA16852 provides a shutdown mode for reduce supply current to the absolute minimum level during periods of nonuse for battery-power conservation. The BA16852 has an internal 300kΩ resistor connected between GND and SD_B pins. The purpose of this resistor is to eliminate any unwanted state changes when shutdown pin is floating. The SD_B input pin should be held high during normal operation when the amplifier is in use. Pulling SD_B low or left floating causes the outputs to mute and the amplifier to enter a low-current state. During the shutdown mode, the DC quiescent current of the circuit does not exceed 0.5μA. _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 21 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Output Filter Application Note Design the BA16852 without the filter if the traces from amplifier to speaker are short (<100mm). Where the speaker is in the same enclosure as the amplifier is a typical application for class-d without a filter. Like wireless handsets and PDAs are great applications for class-d without a filter. Many applications require a ferrite bead filter. The ferrite filter reduces EMI around 30 MHz. When selecting a ferrite bead, choose one with high impedance at high frequencies, but low impedance at low frequencies. Use an LC output filter if there are low frequency (<1 MHz) EMI sensitive circuits and there are long wires from the amplifier to the speaker. Figure 33 & 34 show typical LC and ferrite bead output filters. 22uH OUTP 0.1uF 0.47uF 22uH 0.1uF OUTN Figure 33. Typical LC Output Filter BEAD (600R) OUTP 330pF 470pF BEAD (600R) 330pF OUTN Figure 34. Typical Ferrite Chip Bead Output Filter (Chip bead example : Queen Core / TI321611U601) Board Layout Considerations Place all the external components very close to the BA16852. Placing the decoupling capacitor, CS, close to the BA16852 VDD terminal is very important for the efficiency of the class-d amplifier. Any resistance and inductance in the trace between the device and the capacitor can cause a loss in efficiency. Additionally, the input resistors need to be very close to the BA16852 input terminal, so noise does not couple on the high-impedance nodes between the input resistors and the input amplifier of the BA16852. _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 22 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier PACKAGE DIMENSION 8PIN MSOP PACKAGE CONTACT INFORMATION Biforst Technology Inc. 8F-3, No.26, Tai Yuen St., Jubei City, Hsin-Chu, Taiwan, R.O.C. Tel: 886-3-552-6521; Fax: 886-3-552-6558; Email: [email protected] _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 23 of 24 BA16852 3W Mono Filterless Class-D Audio Power Amplifier Version History Version Date 1.0 1.1 2007.08.23 2007.08.28 Page 2 Description First Release Modify Package Type in Feature _________________________________________________________________________________________________ Biforst Technology, Inc., reserves the right to change product or specifications without notice. Page 24 of 24