APA2120/2121 Stereo 2-W Audio Power Amplifier (with DC_Volume Control) General Description Features • • • • • • • • • • Low operating current with 14mA APA2120/1 is a monolithic integrated circuit, which Improved depop circuitry to eliminate turn-on provides precise DC volume control, and a stereo and turn off transients in outputs bridged audio power amplifiers capable of producing High PSRR 32 steps volume adjustable by DC voltage with hysteresis 2W per channel output power into 4Ω load at 5V, BTL mode Two output modes allowable with BTL and SE modes selected by SE/BTL pin Low current consumption in shutdown mode (50µA) Short Circuit Protection Power off depop circuit integration 2.7W(2.0W) into 3Ω with less than 10% (1.0%) TSSOP-24 with or without thermal pad package improves the power off pop noise and protects the THD+N. The attenuator range of the volume control in APA2120/1 is from 20dB (DC_Vol=0V) to -80dB (DC_Vol=3.54V) with 32 steps. The advantage of internal gain setting can be less components and PCB area. Both of the depop circuitry and the thermal shutdown protection circuitry are integrated in APA2120/1, that reduce pops and clicks noise during power up or shutdown mode operation. It also chip from being destroyed by over temperature and short current failure. To simplify the audio system Applications design, APA2120/1 combines a stereo bridge-tied loads (BTL) mode for speaker drive and a stereo • • NoteBook PC single-end (SE) mode for headphone drive into a LCD Monitor or TV single chip, where both modes are easily switched by the SE/BTL input control pin signal. Besides, the multiple input selection is used for portable audio system. Ordering and Marking Information P ackage C ode R : T S S O P -P * Tem p. R ange I : - 4 0 to 8 5 ° C H a n d lin g C o d e TU : Tube T Y : T ra y A P A 2 1 2 0 /1 H a n d lin g C o d e Tem p. R ange P ackage C ode A P A 2 1 2 0 /1 R : A P A 2 1 2 0 /1 XXXXX TR : Tape & R eel X X X X X - D a te C o d e * TSSOP-P is a standard TSSOP package with a thermal pad exposure on the bottom of the package. ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise customers to obtain the latest version of relevant information to verify before placing orders. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 1 www.anpec.com.tw APA2120/2121 Block Diagram LOUT+ LLINEIN LHPIN MUX RHPIN LOUT- V o lu m e C o n tro l RLINEIN LBYPASS MUX VOLUM E BYPASS BYPASS ROUT+ HP/LINE H P /L IN E SE/BTL ROUT- S E /B T L RBYPASS SHUTDOW N S h u td o w n ckt PCBEEP CLK P C -B E E P ckt C lo c k G e n For APA2121 Absolute Maximum Ratings (Over operating free-air temperature range unless otherwise noted.) Symbol Parameter VDD Supply Voltage Range VIN TA TJ TSTG TS Input Voltage Range, SE/BTL, HP/LINE, SHUTDOWN, PCBEN Operating Ambient Temperature Range Maximum Junction Temperature Storage Temperature Range Soldering Temperature,10 seconds VESD Electrostatic Discharge PD Power Dissipation Rating Unit -0.3 to 6 V -0.3 to VDD+0.3 V -40 to 85 Intermal Limited*1 -65 to +150 260 -3000 to 3000*2 -200 to 200*3 Intermal Limited °C °C °C °C V Note: 1.APA2120/1 integrated internal thermal shutdown protection when junction temperature ramp up to 150°C 2.Human body model: C=100pF, R=1500Ω, 3 positives pulse plus 3 negative pulses 3.Machine model: C=200pF, L=0.5µF, 3 positive pulses plus 3 negative pulses Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 2 www.anpec.com.tw APA2120/2121 Recommended Operating Conditions Supply Voltage, VDD High level threshold voltage, VIH Low level threshold voltage, VIL Min. Max. Unit 4.5 5.5 V SHUTDOWN, PCBEN 2 SE/BTL , HP/LINE SHUTDOWN, PCBEN 4 V 1.0 SE/BTL , HP/LINE Common mode input voltage, VICM V 3 VDD-1.0 V Thermal Characteristics Symbol Parameter R THJA Thermal Resistance from Junction to Ambient in Free Air TSSOP-P* Value Unit 45 K/W * 5 in2 printed circuit board with 2oz trace and copper pad through 9 25mil diameter vias. The thermal pad on the TSSOP_P package with solder on the printed circuit board. Electrical Characteristics VDD=5V, -20°C<TA<85°C (unless otherwise noted) Symbol VDD IDD Parameter Test Condition Supply Voltage Supply Current APA2120/1 Min. Typ. 4.5 Max. 5.5 SE/BTL=0V 14 25 SE/BTL=5V 8.0 15 Unit V mA ISD Supply Current in Shutdown SE/BTL=5V Mode SHUTDOWN=0V 50 µA IIH High input Current 900 nA IIL Low Input Current 900 nA 5 mV VOS Output Differential Voltage Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 3 www.anpec.com.tw APA2120/2121 Electrical Characteristics (Cont.) Operating Characteristics, BTL mode VDD=5V,TA=25°C,RL=4Ω, Gain=2V/V (unless otherwise noted) Symbol PO Parameter Maximum Output Power Test Condition PSRR Power Ripple Rejection Ratio Xtalk S/N Min. Typ. Max. THD=10%, RL=3Ω, Fin=1kHz 2.7 THD=10%, RL=4Ω, Fin=1kHz 2.3 THD=10%, RL=8Ω, Fin=1kHz 1.5 THD=1%, RL=3Ω, Fin=1kHz 2.0 THD=1%, RL=4Ω, Fin=1kHz 1.9 THD=0.5%, RL=8Ω, Fin=1kHz THD+N Total Harmonic Distortion Plus Noise APA2120/1 1 Unit W 1.1 PO=1.5W, RL=4Ω, Fin=1kHz 0.05 PO=1W, RL=8Ω, Fin=1kHz 0.07 % VIN=0.1Vrms, RL=8Ω, CB=1µF, Fin=120Hz 60 dB Channel Separation CB=1µF, RL=8Ω, Fin=1kHz 90 dB Signal to Noise Ratio PO=1.1W, RL=8Ω, A_wieght 95 dB Operating Characteristics, SE mode VDD=5V,TA=25°C,RL=4Ω, Gain=1V/V (unless otherwise noted) Symbol PO Parameter Maximum Output Power THD+N Total Harmonic Distortion Plus Noise Test Condition APA2120/1 Min. Typ. Max. THD=10%, RL=8Ω, Fin=1kHz 400 THD=10%, RL=32Ω, Fin=1kHz 110 THD=1%, RL=8Ω, Fin=1kHz 320 THD=1%, RL=32Ω, Fin=1kHz 90 PO=250mW, RL=8Ω, Fin=1kHz 0.08 PO=75mW, RL=32Ω, Fin=1kHz 0.08 Unit mW % VIN=0.1Vrms, RL=8Ω, CB=1µF, PSRR Power Ripple Rejection Ratio Xtalk Channel Separation S/N Signal to Noise Ratio Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 48 dB CB=1µF, RL=32Ω, Fin=1kHz 100 dB PO=75mW, SE, RL=32Ω, A_wieght 100 dB Fin=120Hz 4 www.anpec.com.tw APA2120/2121 Pin Description GND 1 24 GND PCBEN 2 23 R LIN EIN VO LU M E 3 22 SHUTDO W N LO U T+ 4 21 R O UT+ LLIN EIN 5 20 RHPIN LH PIN 19 PVDD 6 7 RBYPASS G ND 1 24 G ND H P/LIN E 2 23 RLINEIN VO LUM E 3 22 S HU TD O W N LO U T+ 4 21 R OU T+ LLIN EIN 5 20 RHPIN VDD LH PIN 19 VDD 18 PVDD PVDD 6 7 18 PVDD 8 17 C LK RBYPASS 8 17 C LK LO U T- 9 16 R O UT- LO U T- 9 16 R OU T- LBYPASS 10 15 SE/BTL LBYPASS 10 15 SE/BTL BYPASS 11 14 PC-BEEP BYPASS 11 14 PC-BEEP GND 12 13 GND G ND 12 13 G ND APA2120 TO P View APA2121 TO P View Thermal Pad APA2120/1 Bottom View APA2120 APA2121 Multiple Input Selection PCBEEP Control Input SE/BTL PCBEN HP/LINE - Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 5 www.anpec.com.tw APA2120/2121 Pin Function Description Pin Name Config. PCBEN No 1,12, 13,24 2 I/P HP/LINE 2 I/P VOLUME LOUT+ LLINEIN 3 4 5 O/P I/P LHPIN 6 O/P PVDD RBYPASS 7,18 8 I/P LOUT- 9 O/P LBYPASS BYPASS 10 11 I/P PC_BEEP 14 I/P SE/BTL 15 I/P ROUT- 16 O/P CLK VDD 17 19 RHPIN 20 I/P ROUT+ SHUTDOWN 21 22 O/P I/P RLINEIN 23 I/P GND Description Ground connection, Connected to thermal pad. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 BEEP mode control input, active H, for APA2120 only Multi-input selection input, headphone mode when held high, line-in mode when held low for APA2121 only. Input signal for internal volume gain setting. Left channel positive output in BTL mode and SE mode. Left channel line input terminal, selected when HP/LINE is held low. Left channel headphone input terminal, selected when HP/LINE is held high. Supply voltage only for power amplifier. Right channel bypass voltage. Left channel negative output in BTL mode and high impedance in SE mode. Left channel bias voltage generator. Bias voltage generator PCBEP signal input Output mode control input, high for SE output mode and low for BTL mode. Right channel negative output in BTL mode and high impedance in SE mode. Clock signal generator Supply voltage for internal circuit excepting power amplifier. Right channel headphone input terminal, selected when HP/LINE is held high. Right channel positive output in BTL mode and SE mode. It will be into shutdown mode when pull low. Right channel line input terminal, selected when HP/LINE is held low. 6 www.anpec.com.tw APA2120/2121 Control Input Table For APA2120 SE/BTL X L H X SHUTDOWN L H H X PC-BEEP Disable Disable Disable Enable Operating mode Shutdown mode Line input, BTL out HP input, SE out PCBEEP input, BTL out For APA2121 SE/BTL X L L H H X HP/LINE X L H L H X Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 SHUTDOWN L H H H H X 7 PC-BEEP Disable Disable Disable Disable Disable Enable Operating mode Shutdown mode Line input, BTL out HP input, BTL out Line input, SE out HP input, BTL out PCBEEP input, BTL out www.anpec.com.tw APA2120/2121 Typical Application Circuit APA2120 0Ω VDD 0.1µF VDD 1µF LHPIN PVDD LOUT+ 220µF MUX 1kΩ 1µF 1µF RHPIN 1µF LOUT- Volume Control RLINEIN R-LINE R-HP GND LLINEIN L-LINE L-HP 100µF Control Pin LBYPASS MUX Ring SE/BTL 2.2µF VDD BYPASS Sleeve Tip BYPASS Headphone Jack VOLUME 50kΩ 4Ω ROUT+ 220µF 1kΩ VDD 100kΩ 4Ω SE/BTL ROUT- SE/BTL RBYPASS SHUTDOWN Shutdown Signal BEEP Signal 0.47µF PCBEN Signal Shutdown ckt PCBEEP PCBEN Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 CLK Clock Gen PC-BEEP ckt 47nF 8 www.anpec.com.tw APA2120/2121 Typical Application Circuit APA2121 0Ω VDD 0.1µF VDD 1µF GND PVDD LOUT+ LLINEIN L-LINE LHPIN L-HP 100µF 220µF MUX 1kΩ 1µF 4Ω 1µF RLINEIN R-LINE R-HP RHPIN 1µF LBYPASS MUX Ring SE/BTL 2.2µF VDD BYPASS Sleeve Tip BYPASS Headphone Jack VOLUME 50kΩ Control Pin LOUT- Volume Control ROUT+ 220µF 1kΩ HP/LINE HP/LINE Signal HP/LINE VDD 100kΩ 4Ω SE/BTL ROUTSE/BTL RBYPASS Shutdown Signal BEEP Signal SHUTDOWN PCBEEP Shutdown ckt CLK PC-BEEP ckt Clock Gen 0.47µF Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 47nF 9 www.anpec.com.tw APA2120/2121 Volume Control Table_BTL Mode Supply Voltage Vdd=5V Gain(dB) 20 18 16 14 12 10 8 6 4 2 0 -2 -4 -6 -8 -10 -12 -14 -16 -18 -20 -22 -24 -26 -28 -30 -32 -34 -36 -38 -40 -80 High(V) 0.12 0.23 0.34 0.46 0.57 0.69 0.80 0.91 1.03 1.14 1.25 1.37 1.48 1.59 1.71 1.82 1.93 2.05 2.16 2.28 2.39 2.50 2.62 2.73 2.84 2.96 3.07 3.18 3.30 3.41 3.52 5.00 Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 Low(V) 0.00 0.17 0.28 0.39 0.51 0.62 0.73 0.84 0.96 1.07 1.18 1.29 1.41 1.52 1.63 1.74 1.85 1.97 2.08 2.19 2.30 2.42 2.53 2.64 2.75 2.87 2.98 3.09 3.20 3.32 3.43 3.54 Hysteresis(mV) 52 51 50 49 47 46 45 44 43 41 40 39 38 37 35 34 33 32 30 29 28 27 26 24 23 22 21 20 18 17 16 10 Recommended Voltage(V) 0 0.20 0.31 0.43 0.54 0.65 0.77 0.88 0.99 1.10 1.22 1.33 1.44 1.56 1.67 1.78 1.89 2.01 2.12 2.23 2.35 2.46 2.57 2.69 2.80 2.91 3.02 3.14 3.25 3.36 3.48 5 www.anpec.com.tw APA2120/2121 Typical Characteristics THD+N vs. Frequency THD+N vs. Output Power 10 10 VDD=5V RL=3Ω AV=2 BTL 1 THD+N (%) THD+N (%) VDD=5V RL=3Ω Po=1.75W BTL AV=10 AV=2 0.1 f=20kHz 1 0.1 f=1kHz AV=5 f=20Hz 0.01 20 100 1k 0.01 10m 20k 100m THD+N vs. Output Power THD+N vs. Frequency 10 10 VDD=5V RL=4Ω Po=1.5W BTL 1 THD+N (%) THD+N (%) 2 3 Output Power (W) Frequency (Hz) 0.1 1 AV=2 VDD=5V RL=4Ω AV=2 BTL 1 f=20kHz 0.1 f=1kHz AV=5 f=20Hz AV=10 0.01 20 50 100 200 500 1k 2k 5k 0.01 100m 20k Frequency (W) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 200m 500m 800m 2 3 Output Power (W) 11 www.anpec.com.tw APA2120/2121 Typical Characteristics (Cont.) THD+N vs. Frequency THD+N vs. Output Power 10 10 1 0.1 THD+N (%) THD+N (%) VDD=5V RL=8Ω Po=1.0W BTL AV=2 0.01 20 VDD=5V RL=8Ω AV=2 BTL 1 f=20kHz 0.1 AV=5 f=1kHz AV=10 f=20Hz 10 0 1k 0.01 10m 20 k 100m Frequency (Hz) THD+N vs. Output Power 10 VDD=5V RL=8Ω Po=250mW SE VDD=5V RL=8Ω AV=2 BTL 1 1 THD+N (%) THD+N (%) 2 Output Power (W) THD+N vs. Frequency 10 1 AV=1 AV=5 0.1 f=20kHz 0 .1 f=20Hz AV=2.5 0.01 20 100 1k f=1kHz 0 .01 10m 20k Frequency (Hz) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 1 0 0m 5 0 0m Output Power (W) 12 www.anpec.com.tw APA2120/2121 Typical Characteristics (Cont.) THD+N vs. Frequency THD+N vs. Output Power 10 VDD=5V RL=16Ω Po=100mW SE VDD=5V RL=16Ω AV=1 BTL 1 AV=1 AV=2 0.1 THD+N (%) THD+N (%) 10 1 f=20kHz f=20Hz 0.1 f=1kHz AV=2.5 0.01 20 50 100 200 500 1k 2k 5k 0.01 10m 20k 100m Frequency (Hz) Output Power (W) THD+N vs. Output Power THD+N vs. Frequency 10 VDD=5V RL=32Ω Po=75mW SE 5 1 0.1 AV=2.5 THD+N (%) THD+N (%) 10 300m AV=1 VDD=5V RL=32Ω AV=1 BTL f=20kHz 1 0.1 f=20Hz f=1kHz AV=5 0.01 20 100 1k 0.01 10 m 20k Frequency (Hz) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 50 m 10 0m 20 0m Output Power (W) 13 www.anpec.com.tw APA2120/2121 Typical Characteristics (Cont.) THD+N vs. Frequency THD+N vs. Output Swing 10 10 VDD=5V RL=10Ω AV=1 SE 1 0.1 AV=2.5 THD+N (%) THD+N (%) VDD=5V RL=10Ω Vo=1VRMS SE AV=1 1 0.1 f=20kHz f=1kHz f=20Hz AV=5 0.01 20 10 0 1k 0.01 100m 20 k 500m Frequency (Hz) +0 VDD=5V RL=32Ω -2 0 Po=75mW AV=1 SE Crosstalk (dB) VDD=5V RL=8Ω -20 Po=1.0W AV=2 BTL Crosstalk (dB) 3 Crosstalk vs. Frequency +0 -40 -60 R-ch to L-ch 1 00 1k -6 0 -8 0 R-ch to L-ch -1 00 -1 20 20 2 0k Frequency (Hz) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 -4 0 L-ch to R-ch L-ch to R-ch -10 0 -12 0 20 2 Output Swing (VRMS) Crosstalk vs. Frequency -80 1 100 1k 20k Frequency (Hz) 14 www.anpec.com.tw APA2120/2121 Typical Characteristics (Cont.) Noise Floor vs. Frequency Noise Floor vs. Frequency 10 0u 100u VDD=5V RL=32Ω 50 u AV=1 SE No Filter Noise Floor (µVRMS) Noise Floor (µVRMS) 50u 20u A-Weight 10u 5u VDD=5V RL=8Ω AV=2 BTL 2u 1u 20 100 1k 20 u No Filter 10 u A-Weight 5u 2u 1u 20 20k 10 0 Noise Floor vs. Frequency Power Dissipation vs. Output Power 0 .2 VDD=5V RL=10KΩ 5 0 u AV=1 SE 0 .1 8 Power Dissipation (W) Noise Floor (µVRMS) 1 0 0u No Filter 10u A-Weight 5u 2u 0 .1 6 0 .1 4 RL=8Ω 0 .1 2 0 .1 RL=16Ω 0 .0 8 0 .0 6 RL=32Ω 0 .0 4 VDD=5V AV=1 SE 0 .0 2 1u 20 20 k Frequency (Hz) Frequency (Hz) 20u 1k 0 100 1k 20k 0 Frequency (Hz) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 0 .0 5 0 .1 0 .1 5 0 .2 0 .2 5 0 .3 0 .3 5 0 .4 Output Power (W) 15 www.anpec.com.tw APA2120/2121 Typical Characteristics (Cont.) Power Dissipation vs. Output Power Supply Current vs. Supply Voltage 20 1 .8 1 7 .5 RL=3Ω 1 .4 Suuply Current (mA) Power Dissipation (W) 1 .6 1 .2 RL=4Ω 1 0 .8 0 .6 RL=8Ω 0 .4 VDD=5V AV=2 BTL 0 .2 15 BTL 1 2 .5 10 SE 7 .5 5 2 .5 No Load 0 0 1 .8 Output Power (W) 1 .6 1 1 .5 2 1 2 .5 1 .5 2 2 .5 3 3 .5 4 4 .5 5 5 .5 Output Power (W) Supply Voltage (V) Output Power vs. Supply Voltage Output Power vs. Supply Voltage 160 RL=8Ω AV=2 BTL 140 Output Power (mW) 2 .0 0 .5 1 .4 THD+N=10% 1 .2 1 .0 0 .8 THD+N=1% 0 .6 RL=32Ω AV=1 SE 120 100 THD+N=10% 80 60 THD+N=1% 40 0 .4 20 0 .2 0 0 2 .5 3 3 .5 4 4 .5 5 2.5 5 .5 Supply Voltage (V) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 3 3.5 4 4.5 5 5.5 Supply Voltage (V) 16 www.anpec.com.tw APA2120/2121 Typical Characteristics (Cont.) Output Power vs. Load Resistance 3 0.7 VDD=5V AV=2 BTL 2 1.5 1 THD+N=10% 0.5 VDD=5V AV=1 SE 0.6 Output Power (W) 2.5 Output Power (W) Output Power vs. Load Resistance 0.5 0.4 0.3 0.2 THD+N=10% 0.1 THD+N=1% 0 THD+N=1% 0 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 4 8 12 16 20 24 28 32 36 40 44 48 52 56 6064 Load Resistance (Ω) Load Resistance (Ω) Close Loop Response Close Loop Response +12 +6 +4 Loop Gain (dB) Loop Gain (dB) VDD=5V RL=8Ω +10 AV=2 BTL CO=330µF +8 +6 AV=2 AV=5 AV=10 +4 +2 -0 20 VDD=5V RL=32Ω AV=1 SE CO=330µF +2 +0 AV=1 AV=2.5 AV=5 -2 -4 100 1k -6 20 20k Frequency (Hz) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 100 1k 20k Frequency (Hz) 17 www.anpec.com.tw APA2120/2121 Typical Characteristics (Cont.) PSRR vs. Frequency Ripple Rejection Ratio (dB) +0 -2 0 66 VDD=5V Vin=100mVRMS RL=8Ω Cbypass=2.2µF BTL -4 0 SE -6 0 -8 0 20 100 1k 20k Frequency (Hz) Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 18 www.anpec.com.tw APA2120/2121 Application Descriptions BTL Operation BTL Operation (Cont.) The APA2120/1 output stage (power amplifier) has Four times the output power same conditions. A BTL two pairs of operational amplifiers internally, allowed configuration, such as the one used in APA2120/1, for different amplifier configurations. also creates a second advantage over SE amplifiers. Since the differential outputs, ROUT+, ROUT-, OUT+ LOUT+, and LOUT-, are biased at half-supply, no Volume Control am plifier output signal OP1 need DC voltage exists across the load. This eliminates the need for an output coupling capacitor which RL is required in a single supply, SE configuration. OUT- Vbias Circuit OP2 Single-Ended Operation Figure 1: APA2120/1 internal configuration Consider the single-supply SE configuration shown (each channel) The power amplifier’s OP1 gain is setting by internal Application Circuit. A coupling capacitor is required to block the DC offset voltage from reaching the load. unity-gain and input audio signal is come from inter- These capacitors can be quite large (approximately nal volume control amplifier, while the second ampli- 33µF to 1000µF) so they tend to be expensive, oc- fier OP2 is internally fixed in a unity-gain, inverting cupy valuable PCB area, and have the additional configuration. Figure 1 shows that the output of OP1 drawback of limiting low-frequency performance of is connected to the input to OP2, which results in the the system (refer to the Output Coupling Capacitor). output signals of with both amplifiers with identical in The rules described still hold with the addition of the magnitude, but out of phase 180°. Consequently, following relationship: the differential gain for each channel is 2 x (Gain of 1 ≤ 1 << 1 Cbypass x 125kΩ RiCi RLCC SE mode). (1) By driving the load differentially through outputs OUT+ Output SE/BTL Operation and OUT-, an amplifier configuration commonly referred to as bridged mode is established. BTL mode The ability of the APA2120/1 to easily switch between operation is different from the classical single-ended BTL and SE modes is one of its most important costs SE amplifier configuration where one side of its load saving features. This feature eliminates the require- is connected to ground. ment for an additional headphone amplifier in appli- A BTL amplifier design has a few distinct advantages cations where internal stereo speakers are driven in over the SE configuration, as it provides differential BTL mode but external headphone or speakers must drive to the load, thus doubling the output swing for a be accommodated. specified supply voltage. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 19 www.anpec.com.tw APA2120/2121 Application Descriptions (Cont.) Output SE/BTL Operation (Cont.) Output SE/BTL Operation (Cont.) Internal to the APA2120/1, two separate amplifiers Resistor 1kΩ then pulls low the SE/BTL pin, enabling drive OUT+ and OUT- (see Figure 1). The SE/BTL the BTL function. input controls the operation of the follower amplifier Volume Control Function that drives LOUT- and ROUT-. • When SE/BTL is held low, the OP2 is turn on and APA2120/1 has an internal stereo volume control the APA2120/1 is in the BTL mode. whose setting is a function of the DC voltage applied •When SE/BTL is held high, the OP2 is in a high to the VOLUME input pin. The APA2120/1 volume output impedance state, which configures the control consists of 32 steps that are individually se- APA2120/1 as SE driver from OUT+. IDD is reduced lected by a variable DC voltage level on the VOL- by approximately one-half in SE mode. UME control pin. The range of the steps, controlled Control of the SE/BTL input can be a logic-level TTL by the DC voltage, are from 20dB to -80dB. Each source or a resistor divider network or the stereo gain step corresponds to a specific input voltage headphone jack with switch pin as shown in Applica- range, as shown in table. To minimize the effect of tion Circuit. noise on the volume control pin, which can affect the selected gain level, hysteresis and clock delay are 1k Ω implemented. The amount of hysteresis corresponds VDD 100k Ω Control Pin to half of the step width, as shown in volume control Ring graph. SE/BTL Tip Gain_BT L m ode Sleeve APA2021 volum e control curve Forward Backward 20 Headphone Jack 16 Figure 2: SE/BTL input selection by phonejack plug 12 8 In Figure 2, input SE/BTL operates as follows : 4 When the phonejack plug is inserted, the 1kΩ resis- 0 -4 tor is disconnected and the SE/BTL input is pulled -8 high and enables the SE mode. When the input goes -12 -16 high, the OUT- amplifier is shutdown causing the -20 -24 speaker to mute. The OUT+ amplifier then drives -28 through the output capacitor (CC) into the headphone -32 -36 jack. When there is no headphone plugged into the -40 system, the contact pin of the headphone jack is con- -44 0 nected from the signal pin, the voltage divider set up 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 (V) Figure 3: Gain setting vs VOLUME pin voltage by resistors 100kΩ and 1kΩ. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 20 www.anpec.com.tw APA2120/2121 Application Descriptions (Cont.) Volume Control Function (Cont.) Ri vs Gain(BTL) Ri(kΩ) 120 For highest accuracy, the voltage shown in the ‘rec- 100 ommended voltage’ column of the table is used to 80 select a desired gain. This recommended voltage is exactly halfway between the two nearest transitions. 60 The gain levels are 2dB/step from 20dB to -40dB in 40 BTL mode, and the last step at -80dB as mute mode. 20 0 Input Resistance, Ri -40 The gain for each audio input of the APA2120/1 is -30 -20 -10 0 10 20 Gain(dB) Figure 4: Input resistance vs Gain setting set by the internal resistors (Ri and Rf) of volume Input Capacitor, Ci control amplifier in inverting configuration. RF (2) Ri RF (3) BTL Gain = -2 x Ri BTL mode operation brings the factor of 2 in the gain In the typical application an input capacitor, Ci, is re- SE Gain = AV = - quired to allow the amplifier to bias the input signal to the proper DC level for optimum operation. In this case, Ci and the minimum input impedance Ri (10kΩ) equation due to the inverting amplifier mirroring the form a high-pass filter with the corner frequency de- voltage swing across the load. For the varying gain termined in the follow equation : setting, APA2120/1 generates each input resistance FC(highpass)= on figure 4. The input resistance will affect the low 1 2πx10kΩxCi (4) frequency performance of audio signal. The minmum The value of Ci is important to consider as it directly input resistance is 10kΩ when gain setting is 20dB affects the low frequency performance of the circuit. and the resistance will ramp up when close loop gain Consider the example where Ri is 10kΩ and the speci- below 20dB. The input resistance has wide variation fication calls for a flat bass response down to 100Hz. (+/-10%) caused by process variation. Equation is reconfigured as follow : Ci= 1 2πx10kΩxfC (5) Consider to input resistance variation, the Ci is 0.16µF so one would likely choose a value in the range of 0.22µF to 1.0µF. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 21 www.anpec.com.tw APA2120/2121 Application Descriptions (Cont.) Input Capacitor, Ci (Cont.) Effective Bypass Capacitor, Cbypass (Cont.) A further consideration for this capacitor is the leak- The effective capacitance is the Cbypass=(Cb// age path from the input source through the input net- CLbyasss//CRbypass). When absolute minimum work (Ri+Rf, Ci) to the load. This leakage current cost and/or component space is required, one by- creates a DC offset voltage at the input to the ampli- pass capacitor can be used. fier that reduces useful headroom, especially in high To avoid start-up pop noise occurred, the bypass gain applications. For this reason a low-leakage tan- voltage should rise slower than the input bias voltage talum or ceramic capacitor is the best choice. When and the relationship shown in equation (6) should be polarized capacitors are used, the positive side of maintained. 1 1 << Cbypass x 125kΩ 100kΩ x Ci the capacitor should face the amplifier input in most applications as the DC level there is held at VDD/2, (6) The bypass capacitor is fed thru from a 125kΩ resis- which is likely higher that the source DC level. tor inside the amplifier and the 100kΩ is maximum sPlease note that it is important to confirm the ca- input resistance of (Ri+ Rf). Bypass capacitor, Cb, pacitor polarity in the application. values of 3.3µF to 10µF ceramic or tantalum low-ESR Effective Bypass Capacitor, Cbypass capacitors are recommended for the best THD and As other power amplifiers, proper supply bypassing noise performance. is critical for low noise performance and high power The bypass capacitance also effects to the start up supply rejection. time. It is determined in the following equation : The capacitors located on both the bypass and power Tstart up = 5 x (Cbypass x 125KΩ) supply pins should be as close to the device as (7) Output Coupling Capacitor, Cc possible. The effect of a larger bypass capacitor will improve PSRR due to increased supply stability. Typi- In the typical single-supply SE configuration, an out- cal applications employ a 5V regulator with 1.0µF and put coupling capacitor (Cc) is required to block the a 0.1µF bypass capacitor as supply filtering. This DC bias at the output of the amplifier thus preventing does not eliminate the need for bypassing the supply DC currents in the load. As with the input coupling nodes of the APA2120/1. The selection of bypass capacitor, the output coupling capacitor and imped- capacitors, especially Cbypass, is thus dependent ance of the load form a high-pass filter governed by upon desired PSRR requirements, click and pop equation. FC(highpass)= performance. 1 2πRLCC (8) On the chip, there are three bypass pins for used, and they are tied together in the internal circuit. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 22 www.anpec.com.tw APA2120/2121 Application Descriptions (Cont.) Output Coupling Capacitor, Cc (Cont.) Optimizing Depop Circuitry For example, a 330µF capacitor with an 8Ω speaker Circuitry has been included in the APA2120/1 to mini- would attenuate low frequencies below 60.6Hz. The mize the amount of popping noise at power-up and main disadvantage, from a performance standpoint, when coming out of shutdown mode. Popping oc- is the load impedance is typically small, which drives curs whenever a voltage step is applied to the the low-frequency corner higher degrading the bass speaker. In order to eliminate clicks and pops, all response. Large values of CC are required to pass capacitors must be fully discharged before turn-on. low frequencies into the load. Rapid on/off switching of the device or the shutdown function will cause the click and pop circuitry. Power Supply Decoupling, Cs The value of Ci will also affect turn-on pops. (Refer to Effective Bypass Capacitance) The bypass volt- The APA2120/1 provides PVDD and VDD two indepen- age ramp up should be slower than input bias voltage. dent power inputs for used. PVDD is used for power Although the bypass pin current source cannot be amplifier only and VDD is used for volume control modified, the size of Cbypass can be changed to al- amplifier and internal circuit excepting power amplifier. ter the device turn-on time and the amount of clicks The APA2120/1 is a high-performance CMOS audio and pops. By increasing the value of Cbypass, turn- amplifier that requires adequate power supply on pop can be reduced. However, the tradeoff for decoupling to ensure the output total harmonic dis- using a larger bypass capacitor is to increase the turn- tortion (THD) is as low as possible. Power supply on time for this device. There is a linear relationship decoupling also prevents the oscillations causing by between the size of Cbypass and the turn-on time. long lead length between the amplifier and the In a SE configuration, the output coupling capacitor, speaker. The optimum decoupling is achieved by CC, is of particular concern. using two different type capacitors that target on dif- This capacitor discharges through the internal 10kΩ ferent type of noise on the power supply leads. resistors. Depending on the size of CC, the time con- For higher frequency transients, spikes, or digital hash stant can be relatively large. To reduce transients in on the line, a good low equivalent-series-resistance SE mode, an external 1kΩ resistor can be placed in (ESR) ceramic capacitor, typically 0.1µF placed as parallel with the internal 10kΩ resistor. The tradeoff close as possible to the device VDD and PVDD lead for using this resistor is an increase in quiescent works best. For filtering lower-frequency noise current. In the most cases, choosing a small value signals, a large aluminum electrolytic capacitor of of Ci in the range of 0.33µF to 1µF, Cb being equal to 10µF or greater placed near the audio power ampli- 4.7µF and an external 1kΩ resistor should be placed fier is recommended. in parallel with the internal 10kΩ resistor should produce a virtually clickless and popless turn-on. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 23 www.anpec.com.tw APA2120/2121 Application Descriptions (Cont.) Optimizing Depop Circuitry (Cont.) Input HP/LINE Operation (Cont.) A high gain amplifier intensifies the problem as the This logic-low voltage at the SE/BTL pin makes small delta in voltage is multiplied by the gain. So it APA2120 into LINE input mode operation. It becomes is advantageous to use low-gain configurations. HP input mode when phonejack plugged. An internal multiplexor selects the input to connect to Shutdown Function the amplifier based on the state of the HP/LINE pin In order to reduce power consumption while not in of the APA2121. use, the APA2120/1 contains a shutdown pin to ex- • To select the LINE inputs, set HP/LINE pin to low ternally turn off the amplifier bias circuitry. This shutdown feature turns the amplifier off when a logic low level. • To enable the HP(headphone) inputs, set HP/LINE is placed on the SHUTDOWN pin. The trigger point pin to high level. between a logic high and logic low level is typically As APA2121, HP/LINE input multiplexor, and SE/BTL 2.0V. It is best to switch between ground and the sup- output operating mode have independent control ply VDD to provide maximum device performance. paths, which can be used for multiple audio input By switching the SHUTDOWN pin to low, the ampli- system. This function will be the same as APA2120 when HP/LINE and SE/BTL are tied together. fier enters a low-current state, IDD<50µA. APA2120/1 is in shutdown mode, except PC-BEEP detect circuit. PC-BEEP Detection On normal operating, SHUTDOWN pin pull to high APA2120/1 integrates a BEEP detect circuit for level to keeping the IC out of the shutdown mode. NOTEBOOK PC. When BEEP signal is provided on The SHUTDOWN pin should be tied to a definite volt- PCBEEP input pin, the BEEP mode is active. age to avoid unwanted state changes. APA2120/1 will force to BTL mode and the internal gain is fixed at -10dB. The PCBEEP signal becomes Input HP/LINE Operation the amplifier input signal and plays on the speaker APA2120/1 amplifier has two separate inputs for each without coupling capacitor. It will be out of shutdown of the left and right stereo channels. The APA2120 mode whenever BEEP mode is enabled. APA2120/ and APA2121 have different control input by SE/BTL 1 will return to previous setting when it is out of BEEP mode. The input impedance is 100kΩ on PCBEEP and HP/LINE, respectively. APA2120 internal multiplexor is selected by SE/BTL input pin. control input. Refer to the ‘Output SE/BTL Operation’, APA2120 provides extra PCBEN control input signal to force IC into BEEP mode. The BEEP mode will be the voltage divider of 100kΩ and 1kΩ sets the volt- enabled when PCBEN goes to high level. When age at the SE/BTL pin to be approximately 50mV BEEP mode is overridden, the signal from PCBEEP when no phonejack plugged into the system. will pass to speaker directly. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 24 www.anpec.com.tw APA2120/2121 Application Descriptions (Cont.) Clock Generator BTL Amplifier Efficiency (Cont.) APA2120/1 integrates a clock block to avoid volume Note that the efficiency of the amplifier is quite low control function abnormal when VOLUME control sig- for lower power levels and rises sharply as power to nal with spike or noise. APA2120/1 changes each the load is increased resulting in a nearly flat internal step of volume gain after four clock cycles to make power dissipation over the normal operating range. sure control signal ready. It provides 130kHz fre- Note that the internal dissipation at full output power quency if no capacitor place on CLK pin to ground. is less than in the half power range. Calculating the The larger capacitance will slow down the and clock efficiency for a specific system is the key to proper frequency. A capacitor 33nF between CLK to ground power supply design. For a stereo 1W audio system and will generates 147Hz frequency on CLK pin. with 8Ω loads and a 5V supply, the maximum draw on the power supply is almost 3W. BTL Amplifier Efficiency A final point to remember about linear amplifiers An easy-to-use equation to calculate efficiency starts (either SE or BTL) is how to manipulate the terms in out as being equal to the ratio of power from the power the efficiency equation to utmost advantage when supply to the power delivered to the load. possible. Note that in equation, V DD is in the The following equations are the basis for calculating denominator. This indicates that as VDD goes down, amplifier efficiency. efficiency goes up. In other words, use the efficiency Efficiency = PO PSUP analysis to choose the correct supply voltage and (9) speaker impedance for the application. Where : PO = VORMS x VORMS = VPxVP 2RL RL VORMS = VP √2 PSUP = VDD x IDDRMS = VDD x 2VP πRL Po (W) Efficiency (%) IDD(A) VPP(V) PD (W) (10) 0.25 31.25 0.16 2.00 0.55 0.50 47.62 0.21 2.83 0.55 1.00 66.67 0.30 4.00 0.5 1.25 78.13 0.32 4.47 0.35 (11) Efficiency of a BTL configuration : PO VPxVP ) / (VDD x 2VP ) = πVP =( 2VDD PSUP 2RL πRL (12) **High peak voltages cause the THD to increase. Table 1. Efficiency Vs Output Power in 5-V/8Ω BTL Table 1 calculates efficiencies for four different out- Systems put power levels. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 25 www.anpec.com.tw APA2120/2121 Application Descriptions (Cont.) Power Dissipation Power Dissipation (Cont.) Whether the power amplifier is operated in BTL or Once the power dissipation is greater than the maxi- SE modes, power dissipation is a major concern. In mum limit (PD,MAX), either the supply voltage (VDD) must equation13 states the maximum power dissipation be decreased, the load impedance (RL) must be in- point for a SE mode operating at a given supply volt- creased or the ambient temperature should be age and driving a specified load. reduced. SE mode : PD,MAX= VDD2 2π2RL (13) Thermal Pad Considerations In BTL mode operation, the output voltage swing is The thermal pad must be connected to ground. The doubled as in SE mode. Thus the maximum power package with thermal pad of the APA2120/1 requires dissipation point for a BTL mode operating at the special attention on thermal design. If the thermal same given conditions is 4 times as in SE mode. design issues are not properly addressed, the BTL mode : PD,MAX= 4VDD2 2π2RL APA2120/1 4Ω will go into thermal shutdown when (14) driving a 4Ω load. The thermal pad on the bottom of the APA2120/1 Since the APA2120/1 is a dual channel power should be soldered down to a copper pad on the cir- amplifier, the maximum internal power dissipation is cuit board. Heat can be conducted away from the 2 times that both of equations depending on the mode thermal pad through the copper plane to ambient. If of operation. Even with this substantial increase in the copper plane is not on the top surface of the cir- power dissipation, the APA2120/1 does not require extra heatsink. cuit board, 8 to 10 vias of 13 mil or smaller in diam- The power dissipation from eter should be used to thermally couple the thermal equation14, assuming a 5V-power supply and an 8Ω pad to the bottom plane. load, must not be greater than the power dissipation For good thermal conduction, the vias must be plated that results from the equation15 : through and solder filled. The copper plane used to TJ,MAX - TA PD,MAX= θJA (15) conduct heat away from the thermal pad should be as large as practical. For TSSOP-24 package with thermal pad, the ther- If the ambient temperature is higher than 25°C, a ο mal resistance (θJA) is equal to 45 C/W. larger copper plane or forced-air cooling will be re- Since the maximum junction temperature (TJ,MAX) of quired to keep the APA2120/1 junction temperature APA2120/1 is 150οC and the ambient temperature below the thermal shutdown temperature (150°C). In (TA) is defined by the power system design, the maxi- higher ambient temperature, higher airflow rate and/ mum power dissipation which the IC package is able or larger copper area will be required to keep the IC to handle can be obtained from equation16. out of thermal shutdown. Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 26 www.anpec.com.tw APA2120/2121 Packaging Information T S S O P / T S S O P -P ( R eference JE D E C R egistration M O -153) e N 2x E/2 E1 1 2 3 E e/2 D A2 A ( 2) GAUGE PLANE A1 b D1 S EXPOSED THERMAL PAD ZONE E2 0.25 L 1 (L1) ( 3) BOTTOM VIEW (THERMALLY ENHANCED VARIATIONDS ONLY) D im A A1 A2 D D1 e E E1 E2 L L1 R R1 S φ1 φ2 φ3 M illim eters Inches M in. M ax. 1.2 0.00 0.15 0.80 1.05 6.4 (N =20P IN ) 6.6 (N =20P IN ) 7.7 (N =24P IN ) 7.9 (N =24P IN ) 9.6 (N =28P IN ) 9.8 (N =28P IN ) 4.2 B S C (N =20P IN ) 4.7 B S C (N =24P IN ) 3.8 B S C (N =28P IN ) 0.65 B S C 6.40 B S C 4.30 4.50 3.0 B S C (N =20P IN ) 3.2 B S C (N =24P IN ) 2.8 B S C (N =28P IN ) 0.45 0.75 1.0 R E F 0.09 0.09 0.2 0° 8° 12° R E F 12° R E F Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 27 M in. M ax. 0.047 0.000 0.006 0.031 0.041 0.252 (N =20P IN ) 0.260 (N =20P IN ) 0.303 (N =24P IN ) 0.311 (N =24P IN ) 0.378 (N =28P IN ) 0.386 (N =28P IN ) 0.165 B S C (N =20P IN ) 0.188 B S C (N =24P IN ) 0.150 B S C (N =28P IN ) 0.026 B S C 0.252 B S C 0.169 0.177 0.118 B S C (N =20P IN ) 0.127 B S C (N =24P IN ) 0.110 B S C (N =28P IN ) 0.018 0.030 0.039R E F 0.004 0.00 4 0.008 0° 8° 12° R E F 12° R E F www.anpec.com.tw APA2120/2121 Physical Specifications Terminal Material Lead Solderability Solder-Plated Copper (Solder Material : 90/10 or 63/37 SnPb) Meets EIA Specification RSI86-91, ANSI/J-STD-002 Category 3. Reflow Condition (IR/Convection or VPR Reflow) temperature Reference JEDEC Standard J-STD-020A APRIL 1999 Peak temperature 183°C Pre-heat temperature Time Classification Reflow Profiles Convection or IR/ Convection Average ramp-up rate(183°C to Peak) 3°C/second max. 120 seconds max Preheat temperature 125 ± 25°C) 60 – 150 seconds Temperature maintained above 183°C Time within 5°C of actual peak temperature 10 –20 seconds Peak temperature range 220 +5/-0°C or 235 +5/-0°C Ramp-down rate 6 °C /second max. 6 minutes max. Time 25°C to peak temperature VPR 10 °C /second max. 60 seconds 215-219°C or 235 +5/-0°C 10 °C /second max. Package Reflow Conditions pkg. thickness ≥ 2.5mm and all bgas Convection 220 +5/-0 °C VPR 215-219 °C IR/Convection 220 +5/-0 °C pkg. thickness < 2.5mm and pkg. volume ≥ 350 mm³ Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 28 pkg. thickness < 2.5mm and pkg. volume < 350mm³ Convection 235 +5/-0 °C VPR 235 +5/-0 °C IR/Convection 235 +5/-0 °C www.anpec.com.tw APA2120/2121 Reliability test program Test item SOLDERABILITY HOLT PCT TST ESD Latch-Up Method MIL-STD-883D-2003 MIL-STD-883D-1005.7 JESD-22-B, A102 MIL-STD-883D-1011.9 MIL-STD-883D-3015.7 JESD 78 Description 245°C , 5 SEC 1000 Hrs Bias @ 125 °C 168 Hrs, 100 % RH , 121°C -65°C ~ 150°C, 200 Cycles VHBM > 2KV, VMM > 200V 10ms , Itr > 100mA Carrier Tape & Reel Dimensions D P Po t E P1 Bo F W Ko Ao D1 T2 J C A B T1 Application TSSOP- 24 A B C J T1 T2 W P E 330 ±1 100 ref 13 ±0.5 2 ±0.5 16.4 ±0.2 2 ±0.2 16 ±0.3 12 ±0.1 1.75±0.1 F D D1 Po P1 Ao Bo Ko t 7.5 ±0.1 1.5 +0.1 1.5 min 4.0 ±0.1 2.0 ±0.1 6.9 ±0.1 8.3 ±0.1 1.5 ±0.1 0.3±0.05 Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 29 www.anpec.com.tw APA2120/2121 Cover Tape Dimensions Application TSSOP- 24 Carrier Width 16 Cover Tape Width 21.3 Devices Per Reel 2000 Customer Service Anpec Electronics Corp. Head Office : 5F, No. 2 Li-Hsin Road, SBIP, Hsin-Chu, Taiwan, R.O.C. Tel : 886-3-5642000 Fax : 886-3-5642050 Taipei Branch : 7F, No. 137, Lane 235, Pac Chiao Rd., Hsin Tien City, Taipei Hsien, Taiwan, R. O. C. Tel : 886-2-89191368 Fax : 886-2-89191369 Copyright ANPEC Electronics Corp. Rev. A.1 - Mar., 2003 30 www.anpec.com.tw