Tai-1 Microelectronics TMPA2156D2 Preliminary www.taimec.com.tw Rev.1.0 September 7, 2005 0.73W/CH STEREO CLASS-D AUDIO POWER AMPLIFIER GENERAL DESCRIPTION FEATURES The TMPA2156D2 is a STEREO class-D audio power amplifier ♦ 2.5V to 6V Single Supply IC. With SE(Single-Ended) configuration, it delivers up to ♦ Up to 0.73W/CH at 5V, 3 ohms 0.73W/CH power into a 3 ohms load or 0.6W/CH power into a 4 ohm load or 0.33W/CH power into an 8 ohm load. No external heat-sink is required. ♦ Up to 85% Power Efficiency ♦ Automatic output power control (APC) ♦ 2.2mA Quiescent Current at 5V For multiple-input applications, independent gain control and ♦ Less Than 0.2uA Shutdown Current corner frequency can be implemented by summing the input ♦ Popless Power-Up, Shutdown and Recovery sources through resistor ratio and input capacitor values. Automatic voltage gain control makes the best use of battery. ♦ Single-Ended output ♦ Thermal Shutoff and Automatic Recovery ♦ Short-Circuit Protection Analog input signal is converted into digital output which drives ♦ directly to the speaker. High power efficiency is achieved due to Package digital output at the load. The audio information is embedded in PWM(Pulse Width Modulation). APPLICATIONS TSSOP8, SOP8 Available For best performance, please refer to //www.taimec.com.tw/data/Tmpa2155EVM/tmpa2156d2EVM.pdf Multimedia application includes Cellular Phones, PDAs, 2.1 for PCB layout. channel, USB audio. It is also ideal for other portable devices like Wireless Radios. REFERENCE CIRCUIT Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 1 TMPA2156D2 Preliminary Tai-1 Microelectronics www.taimec.com.tw Rev.1.0 September 7, 2005 TOP VIEW (Please email [email protected] for complete datasheet.) Tai-1 Microelectronics reserves the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice. Customers are responsible for their products and applications using Tai-1 Microelectronics components. Note that the external components or PCB layout should be designed not to generate abnormal voltages to the chip to prevent from latch up which may cause damage to the device. Typical Application C3 1uF C7 10uF VDD VDD R7 3k + C4 1uF C5 1uF L1 R2 100 VI1 C1 C2 VI2 0.47uF 0.47uF 22k 22k R4 R5 1 2 3 4 VO1 GND IN1 IN2 Vo2 8 VDD7 VDDA 6 SDNB5 VDDA R3 R1 100 + 33uH 100 SDNB C8 VO1 1000uF L2 R6 100K C9 VO2 1000uF C6 1uF R8 3k R9 3k S1 switch 2156D2 PHONEJACK STEREO + 33uH JP1 J1 R13 3k C10 + 100uF VDD ABSOLUTE MAXIMUM RATINGS Over operating free-air temperature range unless otherwise noted(1) Supply voltage, VDD In normal mode -0.3V to 6V V -0.3V to 7V V -0.3V to VDD+0.3V V In shutdown mode Input voltage, V I Continuous total power dissipation Operating free-air temperature, TA See package dissipation ratings 。C -20 to 85 Operating junction temperature, TJ -20 to 150 Storage temperature, Tstg -40 to 150 。C 。C (1) Stresses beyond those listed under”absolute maximum ratings” may cause permanent damage to 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. Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 2 TMPA2156D2 Preliminary Tai-1 Microelectronics www.taimec.com.tw Rev.1.0 September 7, 2005 RECOMMENDED OPERATING CONDITONS MIN Supply voltage, VDD NOM MAX UNIT 2.5 6 V V High-level input voltage, V IH SDNB 2 VDD Low-level input voltage, VIL SDNB 0 0.8 V 85 。C Operating free-air temperature, TA -20 PACKAGE DISSIPATION RATINGS PACKGE SOP8 DERATING TA ≤ 25。C TA = 70。C TA = 85。C FACTOR POWER RATING POWER RATING POWER RATING 6.39mW/。C 0.799W 0.511W 0.415W ELECTRICAL CHARACTERISTICS TA=25。C (unless otherwise noted) PARAMETER PSRR Power supply rejection ratio TEST CONDITIONS MIN VDD=VDDA=2.5V to 5.5V VDD=VDDA=2.5V to 5.5V, CMRR Common mode rejection ratio │IIH│ High-level input current VDD=VDDA=5.5V, VI=5.8V (SDNB) │IIL│ Low-level input current VDD=VDDA=5.5V, VI=-0.3V (SDNB) IQ Quiescent current VDD=VDDA=5V, no load IQ (SD) Shutdown current rDS(on) Static output resistance VDD=VDDA=5.5V f(sw) Switching frequency VDD=VDDA=2.5V to 5.5V *Av Voltage gain VDD=VDDA=2.5V to 5.5V, RL=8Ω RSDN Resistance from shutdown to GND V(SDNB)=5V ZI Input impedance VIC=1Vpp, RL=8Ω TYP MAX UNIT -75 -55 dB -55 -50 dB μA 30 V(SDNB)=0.8V, VDD=VDDA=2.5V to 5.5V 1 μA 2.2 3 mA 0.2 0.5 μA 600 mΩ 200 250 300 kHz 17 21 25 V/V 200 12 15 kΩ 18 kΩ *The gain of the amplifier is determined by, for VDD=VDDA =2.5V to 5.5V Gain = 320kohms Ri + 15kohms where Ri is the external serial resistance at the input pin. Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 3 Preliminary Tai-1 Microelectronics www.taimec.com.tw TMPA2156D2 Rev.1.0 September 7, 2005 OPERATING CHARACTERISTICS TA=25。C, RL=8Ω speaker (unless otherwise noted) PARAMETER TEST CONDITIONS RL=8Ω PO Output power/CH THD+N RL=4Ω Total harmonic distortion plus noise MIN TYP MAX UNIT 0.33 VDD=VDDA=5V. THD+N=10%,f=1kHz. 0.6 RL=3Ω 0.73 VDD=VDDA=5V, PO=0.2W, RL=8Ω, f=1kHz 0.55 VDD=VDDA=5V, PO=0.3W, RL=4Ω, f=1kHz 0.55 VDD=VDDA=5V, PO=0.4W, RL=3Ω, f=1kHz 0.64 W % SNR Signal-to-noise ratio VDD=VDDA=5V, PO=1W, RL=8Ω 85 dB Crosstalk Crosstalk between outputs VDD=AVDD=5V, PO=1W RL=8Ω -60 dB TERMINAL FUNCTIONS TERMINAL I/O NAME DESCRIPTION PIN NO GND 2 I Digital ground IN2 4 I Channel 2 input IN1 3 I Channel 1 input SDNB 5 I Shutdown (active low logic) VDD 7 I Digital Power supply VDDA 6 I Analog Power supply VO1 1 O Channel 1 output VO2 8 O Channel 2 output TYPICAL CHARACTERISTICS Note 1. Input coupling 1µF capacitors are used for all measurements. 2. LC filter is used for THD+N measurement and power efficiency measurement. 3. Characteristic frequency of the LC filter is set 41KHz unless otherwise specified. Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 4 Tai-1 Microelectronics TMPA2156D2 Preliminary www.taimec.com.tw Rev.1.0 September 7, 2005 APPLICATION INFORMATION Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 5 Tai-1 Microelectronics Preliminary www.taimec.com.tw TMPA2156D2 Rev.1.0 September 7, 2005 l Input Resistors and Gain The gain of the amplifier is determined by, for VDD=VDDA =2.5V to 5.5V Gain = 320kohms where Ri is the external serial resistance at the input pin. Ri + 15kohms Note:Please refer to document 010 APP for more application examples. Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 6 Preliminary Tai-1 Microelectronics www.taimec.com.tw TMPA2156D2 Rev.1.0 September 7, 2005 DETAILED DESCRIPTION Efficiency The output transistors of a class D amplifier act as switches. The power loss is mainly due to the turn on resistance of the output transistors when driving current to the load. As the turn on resistance is so small that the power loss is small and the power efficiency is high. With 8 ohm load the power efficiency can be better than 85%. Shutdown The shutdown mode reduces power consumption. A LOW at shutdown pin forces the device in shutdown mode and a HIGH forces the device in normal operating mode. Shutdown mode is useful for power saving when not in use. This function is useful when other devices like earphone amplifier on the same PCB are used but class D amplifier is not necessary. Internal circuit for shutdown is shown below. Pop-less The setup time for the internal circuitry to be stable to drive the speaker is quite fast (<100ms). But for Single-ended outputs the set up time for the output circuit to charge up the output coupling capacitor (=1000uF) to half power voltage is quite long. As shown in the following diagram, the RC constant caused by the voltage divider of equivalent resistance of 1.5k ohms(3kohms//3kohms) and the capacitance of 1000uF of the output coupling capacitor is 1.5 seconds. So to save pop noise the shutdown pin(SDNB) has to be LOW during power up. In addition the shutdown pin has to stay LOW for about 5 seconds to wait for the output coupling capacitor to be charged to half supply voltage. Class-D amplifier + 1000uF + 3k 3k PVCC Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 7 Tai-1 Microelectronics TMPA2156D2 Preliminary www.taimec.com.tw Rev.1.0 September 7, 2005 Voltage gain The voltage gain is defined in the table on page 3. For lower voltage gain one can add external input resistors to input pins. Automatic output Power Control (APC) The voltage gain is self adjusted in the chip over voltage range. This means that, regardless supply voltage change, the output power keeps about the same for a given input level from VDD=5.5v to 2.5v. It allows the best use of the battery. Output filter Ferrite bead filter can be used for EMI purpose. The ferrite filter reduces EMI around 1 MHz and higher(FCC and CE only test radiated emissions greater than 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/or there are long wires from the amplifier to the speaker. EMI is also affected by PCB layout and the placement of the surrounding components. The suggested LC values for different speaker impendence are showed in following figures for reference. Typical LC Output Filter, Speaker Impedance=4Ω Typical LC Output Filter, Speaker Impedance=6Ω & 8Ω Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 8 Tai-1 Microelectronics Preliminary www.taimec.com.tw TMPA2156D2 Rev.1.0 September 7, 2005 Typical Ferrite Chip Bead Filter (Chip bead example:遠越科技 KML2012Q102N 1kohms@100MHz, DCR=0.2ohms, I=1A) EARPHONE USE Class-D output can be used to drive earphone. However to avoid high power to overdrive earphone and to prevent human ear to accidentally be hurt, a resistor has to be put in series with the earphone speaker. Typically a resistor of 330 ohms is adequate for this purpose. Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 9 Tai-1 Microelectronics Preliminary www.taimec.com.tw TMPA2156D2 Rev.1.0 September 7, 2005 Over temperature protection A temperature sensor is built in the device to detect the temperature inside the device. When a high temperature around 145oC and above is detected the switching output signals are disabled to protect the device from over temperature. Automatic recovery circuit enables the device to come back to normal operation when the internal temperature of the device is below around 120oC. Over temperature protection A temperature sensor is built in the device to detect the temperature inside the device. When a high temperature around 145oC and above is detected the switching output signals are disabled to protect the device from over temperature. Automatic recovery circuit enables the device to come back to normal operation when the internal temperature of the device is below around 120oC. Over current protection A current detection circuit is built in the device to detect the switching current of the output stages of the device. It disables the device when the current is beyond about 3.5amps. It protects the device when there is an accident short between outputs or between output and power/gnd pins. It also protects the device when an abnormal low impedance is tied to the output. High current beyond the specification may potentially causes electron migration and permanently damage the device. Shutdown or power down is necessary to resolve the protection situation. There is no automatic recovery from over current protection. Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 10 Preliminary Tai-1 Microelectronics www.taimec.com.tw TMPA2156D2 Rev.1.0 Physical Dimensions September 7, 2005 ( IN MILLIMETERS) E 1 H 5 8 4 0.05TYP. 0.016TYP. 0.063 0.120 SYMBOLS MIN. MAX. A 0.053 0.069 A1 0.004 0.010 D 0.189 0.196 E 0.150 0.157 H 0.228 0.244 SOP8 Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 11 TMPA2156D2 Preliminary Tai-1 Microelectronics www.taimec.com.tw Rev.1.0 Physical Dimensions ( IN MILLIMETERS) SYMBOLS MIN. NDM. MAX. A - - 1.20 A1 0.05 - 0.15 A2 0.96 1.01 1.06 D 2.90 3.00 3.10 E E1 September 7, 2005 6.40 BSC 4.30 4.40 4.50 TSSOP8 Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 12 Tai-1 Microelectronics Preliminary www.taimec.com.tw TMPA2156D2 Rev.1.0 September 7, 2005 IMPORTANT NOTICE Tai-1 Microelectronics Corp. reserves the right to make changes to its products and services and to discontinue any product or service without notice. Customers should obtain the latest relevant information for reference. Testing and quality control techniques are used to screen the parameters. Testing of all parameters of each product is not necessarily performed. Tai-1 Microelectronics Corp. assumes no liability for applications assistance or customer product design. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. Reproduction of information in data sheets or related documentation is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Tai-1 Microelectronics Corp. is not responsible or liable for such altered documentation. Resale of Tai-1 Microelectronics Corp. products or services with statements different from the parameters stated by Tai-1 Microelectronics Corp. for that product or service voids all express and any implied warranties. Tai-1 Microelectronics Corp. is not responsible or liable for any such statements. Copyright ©2005,Tai-1 Microelectronics Corp. Copyright ©2005, Tai-1 Microelectronics Corp. PDF created with pdfFactory trial version www.pdffactory.com 13