G1426 Global Mixed-mode Technology Inc. 2.2W Stereo Audio Amplifier Features General Description Depop Circuitry Integrated Output Power at 10% THD+N, VDD=5V The G1426 is a stereo audio power amplifier in 20pin TSSOP package. It can deliver 2W continuous RMS power into 4Ω load per channel in Bridge-Tied Load (BTL) mode at 5V supply voltage under 1% THD. To simplify the audio system design in the notebook application, The G1426 supports the Bridge-Tied Load (BTL) mode for driving the speakers. For the low current consumption applications, the SHDN mode is supported to disable the G1426 when it is idle. The current consumption can be further reduced to below 2µA. --2.2W/CH (typical) into a 4Ω Ω Load Output Power at 1% THD+N, VDD=5V --2W/CH (typical) into a 4Ω Ω Load --1.2W/CH (typical) into a 8Ω Ω Load Bridge-Tied Load (BTL) Shutdown Control Available Thermal protection Surface-Mount Power Package 20-Pin TSSOP-P Applications Stereo Power Amplifiers for Notebooks or Ordering Information Desktop Computers Multimedia Monitors Stereo Power Amplifiers for Portable Audio ORDER MARKING NUMBER Systems G1426D5X G1426F2X G1426 G1426 TEMP. RANGE PACKAGE -40°C to +85°C TSSOP-20L -40°C to +85°C TSSOP-20L (FD) Note: X Specify the packing type U: Tape & Reel T: Tube * TSSOP-20L (FD): Thermal Pad Pin Configuration G1426 GND/HS SHUTDOWN 1 20 GND/HS 2 19 GND/HS +OUTA 3 18 +OUTB VDD 4 17 VDD -OUTA 5 -INA 6 16 15 -OUTB -INB BYPASS GND/HS 7 14 +INA 8 13 +INB NC 9 12 NC GND/HS 10 11 NC Thermal Pad Top View 20Pin TSSOP Bottom View TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.0 Dec 04, 2003 1 G1426 Global Mixed-mode Technology Inc. Absolute Maximum Ratings Power Dissipation (1) TA ≤ 25°C………………………………………….2.7W TA ≤ 70°C………………………………………….1.7W TA ≤ 85°C………………….………………………1.4W Electrostatic Discharge, VESD Human body mode..…………………….-3000 to 3000(2) Supply Voltage, VCC…………………..…...…….……...6V Operating Ambient Temperature Range TA…….…………………………….……….-40°C to +85°C Maximum Junction Temperature, TJ…..……….….150°C Storage Temperature Range, TSTG….….-65°C to+150°C Soldering Temperature, 10seconds, TS……….……260°C Note: (1) : Recommended PCB Layout (2) : Human body model : C = 100pF, R = 1500Ω, 3 positive pulses plus 3 negative pulses Electrical Characteristics DC Electrical Characteristics, VDD = 5.0V, TA=+25°C, unless otherwise noted PARAMETER Supply Current DC Differential Output Voltage IDD in Shutdown SYMBOL IDD VO(DIFF) ISD CONDITION VDD = 5V VDD = 5V,Gain = 2 VDD = 5V MIN TYP MAX UNIT - 8.5 5 0.1 15 50 2 mA mV µA MIN TYP MAX UNIT - 2 1.25 2.5 1.6 300 100 10 20 65 75 80 2 90 55 - (AC Operation Characteristics, VDD = 5.0V, TA=+25°C, RL = 4Ω Ω, unless otherwise noted) PARAMETER Output power (each channel) see Note Total harmonic distortion plus noise Maximum output power bandwidth Phase margin Power supply ripple rejection Channel-to-channel output separation Input impedance Signal-to-noise ratio Output noise voltage SYMBOL P(OUT) THD+N BOM PSRR CONDITION THD = 1%, BTL, RL = 4Ω THD = 1%, BTL, RL = 8Ω THD = 10%, BTL, RL = 4Ω THD = 10%, BTL, RL = 8Ω PO = 1.6W, BTL, RL = 4Ω PO = 1W, BTL, RL = 8Ω VI = 1V, RL = 10KΩ, G = 1 G = 10, THD = 1% RL = 4Ω, Open Load f = 120Hz f = 1kHz ZI Vn PO = 500mW, BTL Output noise voltage W m% kHz ° dB dB MΩ dB µV (rms) Note :Output power is measured at the output terminals of the IC at 1kHz. TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.0 Dec 04, 2003 2 Global Mixed-mode Technology Inc. G1426 Pin Description PIN NAME I/O FUNCTION 1 SHUTDOWN I Shutdown mode control signal input, places entire IC in shutdown mode when held high, IDD is below 2µA. 2,7,10,19,20 GND/HS 3 +OUTA Ground connection for circuitry, directly connected to thermal pad. 4,17 VDD 5 -OUTA O A channel - output 6 -INA I A channel input signal 8 +INA I A channel positive input of OPAMP, biasing DC operation of OPAMP O A channel + output Supply voltage for circuitry. 9 NC I NC 11 NC I NC 12 NC 13 +INB 14 BYPASS 15 -INB NC I B channel positive input of OPAMP, biasing DC operation of OPAMP Connect to voltage divider for internal mid-supply bias. I B channel input signal 16 -OUTB O B channel - output 18 +OUTB O B channel + output TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.0 Dec 04, 2003 3 G1426 Global Mixed-mode Technology Inc. Typical Characteristics Table of Graphs FIGURE vs Frequency 2,4,6,9,11 vs Output power 1,3,5,7,8,10 Output noise voltage vs Frequency 13 Supply ripple rejection ratio vs Frequency 12 Crosstalk vs Frequency 14 Closed loop response vs Frequency 17 vs supply voltage 15 vs supply voltage 16 vs Load resistance 18 vs Output power 19,20 THD +N Total harmonic distortion plus noise Vn IDD Supply current PO Output power PD Power dissipation TOTAL HARMONIC DISTORTION PLUS NOISE TOTAL HARMONIC DISTORTION PLUS NOISE vs OUTPUT POWER vs FREQUENCY 10 10 5 5 20kHz 2 2 1 Po=1.8W 1 1kHz 0.5 0.5 % % 0.2 0.2 0.1 20Hz 0.02 0.01 3m 5m Ver: 1.0 Dec 04, 2003 10m 20m 50m 100m 200m 500m 1 VDD=5V RL=3Ω BTL Av=-2V/V 0.1 VDD=5V RL=3Ω BTL Av=-2V/V 0.05 0.05 0.02 2 0.01 20 3 50 100 200 500 1k W Hz Figure 1 Figure 2 4 2k 5k 10k 20k TEL: 886-3-5788833 http://www.gmt.com.tw G1426 Global Mixed-mode Technology Inc. TOTAL HARMONIC DISTORTION PLUS NOISE TOTAL HARMONIC DISTORTION PLUS NOISE vs OUTPUT POWER vs FREQUENCY 10 10 5 5 20kHz 2 2 1 0.5 0.5 1kHz % 0.2 0.2 0.1 20Hz 5m 10m 20m 50m 100m 200m 500m 1 VDD=5V RL=4Ω BTL Po=2W Av=-1V/V 0.1 VDD=5V RL=4Ω BTL Av=-2V/V 0.02 0.01 3m Av=-2V/V 1 % 0.05 Av=-4V/V 0.05 0.02 2 0.01 20 3 50 100 200 500 1k 2k 5k 10k 20k W Hz Figure 3 Figure 4 TOTAL HARMONIC DISTORTION PLUS NOISE TOTAL HARMONIC DISTORTION PLUS NOISE vs OUTPUT POWER vs FREQUENCY 10 10 VDD=5V RL=8Ω BTL Av=-2V/V 5 20kHz 2 5 2 1 1 0.5 1kHz % Av=-2V/V 0.2 0.2 0.1 0.1 20Hz 0.05 0.02 0.01 2m Av=-1V/V 0.02 5m 10m 20m 50m 100m 200m 500m 1 0.01 20 2 W 50 100 200 500 1k 2k 5k 10k 20k Hz Figure 6 Figure 5 Ver: 1.0 Dec 04, 2003 Av=-4V/V 0.5 % 0.05 VDD=5V RL=8Ω BTL Po=1W 5 TEL: 886-3-5788833 http://www.gmt.com.tw G1426 Global Mixed-mode Technology Inc. TOTAL HARMONIC DISTORTION PLUS NOISE TOTAL HARMONIC DISTORTION PLUS NOISE vs OUTPUT POWER vs OUTPUT POWER 10 10 VDD=5V RL=32Ω BTL Av=-2V/V 5 2 20kH 1 5 20kHz 2 1 1kHz 0.5 0.5 % % 0.2 0.2 1kHz 0.1 0.1 0.05 0.05 20Hz 0.02 0.01 1m 2m 0.02 5m 10m 20m 50m 100m 200m 500m 0.01 1m 1 VDD=3.3V RL=4Ω BTL Av=-2V/V 2m 5m 20Hz 10m 20m 50m 100m 200m 500m 1 W W Figure 7 Figure 8 TOTAL HARMONIC DISTORTION PLUS NOISE TOTAL HARMONIC DISTORTION PLUS NOISE vs FREQUENCY vs OUTPUT POWER 10 5 2 1 10 VDD=3.3V RL=4Ω BTL Po=0.75W 5 1 0.5 % 0.2 0.5 Av=-2V/V 0.2 0.1 0.05 0.05 Av=-1V/V 0.02 50 100 200 0.02 500 1k 2k 5k 10k 0.01 1m 20k Hz VDD=3.3V RL=8Ω BTL Av=-2V/V 2m 5m 20Hz 10m 20m 50m 100m 200m 500m 1 W Figure 10 Figure 9 Ver: 1.0 Dec 04, 2003 1kHz % 0.1 0.01 20 20kHz 2 Av=-4V/V 6 TEL: 886-3-5788833 http://www.gmt.com.tw G1426 Global Mixed-mode Technology Inc. TOTAL HARMONIC DISTORTION PLUS NOISE SUPPLY RIPPLE REJECTION RATIO vs FREQUENCY vs FREQUENCY +0 10 -5 -10 5 2 1 VDD=3.3V RL=8Ω BTL Po=0.45W -15 -20 -25 -30 Av=-4V/V -35 VDD=5V RL=4Ω CB=4.7µF Vripple=0.5Vpp -40 0.5 -45 d B % Av=-2V/V 0.2 -50 -55 -60 -65 0.1 BTL Mode -70 -75 0.05 -80 -85 0.02 0.01 20 Av=-1V/V 50 100 -90 -95 200 500 1k 2k 5k 10k -100 20 20k 50 100 200 500 Hz Figure 11 10k 20k -30 90u -35 80u 70u -40 60u -45 -50 50u -55 30u 5k CHANNEL SEPARATION 100u V 2k Figure 12 OUTPUT NOISE VOLTAGE vs FREQUENCY 40u 1k Hz VDD=5V RL=4Ω BTL Mode 20kHz VDD=5V Po=1.5W RL=4Ω BTL -60 d B Channel A to B -65 -70 -75 20u -80 -85 Channel B to A -90 -95 10u 20 50 100 200 500 1k 2k 5k 10k -100 20 20k Hz 100 200 500 1k 2k 5k 10k 20k Hz Figure 13 Ver: 1.0 Dec 04, 2003 50 Figure 14 7 TEL: 886-3-5788833 http://www.gmt.com.tw G1426 Global Mixed-mode Technology Inc. OUTPUT POWER vs SUPPLY VOLTAGE SUPPLY CURRENT vs SUPPLY VOLTAGE 3 9 Stereo BTL 8 THD+N=1% BTL Each Channel 2.5 Output Power(W) Supply Current(mA) 8.5 7.5 2 RL=4Ω RL=3Ω 1.5 7 6.5 6 1 RL=8Ω 0.5 5.5 0 5 3 3.5 4 4.5 5 5.5 2.5 6 3.5 4.5 5.5 6.5 Supply Voltage(V) Supply Voltage(V) Figure 15 Figure 16 OPEN LOOP RESPONSE Figure 17 Ver: 1.0 Dec 04, 2003 8 TEL: 886-3-5788833 http://www.gmt.com.tw G1426 Global Mixed-mode Technology Inc. OUTPUT POWER vs LOAD RESISTANCE POWER DISSIPATION vs OUTPUT POWER 1.8 2.5 1.5 VDD=5V 1 1.2 1 RL=4Ω 0.8 0.6 0.4 0.5 VDD=5V BTL Each Channel RL=8Ω 0.2 VDD=3.3V 0 0 0 5 10 15 20 25 30 35 0 Figure 18 1 1.5 2 2.5 Figure 19 POWER DISSIPATION vs OUTPUT POWER 0.8 0.7 0.5 Po-Output Power(W) Load Resistance(Ω) Power Dissipation(W) RL=3Ω 1.4 Power Dissipation Output Power(W) 1.6 THD+N=1% BTL Each Channel 2 Recommended PCB Layout Unit:mm RL=3Ω 0.6 0.5 RL=4Ω 0.4 0.3 0.2 VDD=3.3V BTL Each Channel RL=8Ω 0.1 0 0 0.2 0.4 0.6 0.8 1 1.2 Po-Output Power(W) Figure 20 Ver: 1.0 Dec 04, 2003 9 TEL: 886-3-5788833 http://www.gmt.com.tw G1426 Global Mixed-mode Technology Inc. Block Diagram VDD CS + 1µF TANT RF 20kΩ Audio Input C1 R1 6 -IN A 20kΩ 8 +IN A 4,17 - - OUT A 5 Amp A1 + 1µF 20kΩ 20kΩ 50kΩ +OUT A 14 RL 8Ω 20kΩ 3 Amp A2 Bypass + VDD/2 + CB 0.33µF 50kΩ Audio Input R1 C1 1µF 20kΩ 15 -IN B 13 +IN B - OUT B 16 Amp A1 + RF 20kΩ 20kΩ 20kΩ RL 8Ω 20kΩ 9,11,12 NC +OUT B - 18 Amp A2 + 1 Shutdown GND 2,7,10,19,20 Application Circuits 4,17 6 -IN A 8 +IN A VDD - OUT A 5 AmpA1 + 20kΩ 20kΩ 20kΩ 50kΩ 14 Bypass +OUT A 3 AmpA2 + VDD/2 50kΩ 15 -IN B 13 +IN B - OUT B 16 AmpA1 + 20kΩ 20kΩ 20kΩ 9,11,12 NC Amp A2 +OUT B 18 + 1 Shutdown GND 2,7,10,19,20 TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.0 Dec 04, 2003 10 G1426 Global Mixed-mode Technology Inc. Application Information Bridged-Tied Load Mode Operation G1426 has two linear amplifiers to drive both ends of the speaker load in Bridged-Tied Load (BTL) mode operation. Figure 1 shows the BTL configuration. The differential driving to the speaker load means that when one side is slewing up, the other side is slewing down, and vice versa. This configuration in effect will double the voltage swing on the load as compared to a ground reference load. In BTL mode, the peak-to-peak voltage VO(PP) on the load will be two times than a ground reference configuration. The voltage on the load is doubled, this will also yield 4 times output power on the load at the same power supply rail and loading. Another benefit of using differential driving configuration is that BTL operation cancels the dc offsets, which eliminates the dc coupling capacitor that is needed to cancelled dc offsets in the ground reference configuration. Low-frequency performance is then limited only by the input network and speaker responses. Cost and PCB space can be minimized by eliminating the dc coupling capacitors. Optimizing DEPOP Operation Circuitry has been implemented in G1426 to minimize the amount of popping heard at power-up and when coming out of shutdown mode. Popping occurs whenever a voltage step is applied to the speaker and making the differential voltage generated at the two ends of the speaker. To avoid the popping heard, the bypass capacitor should be chosen promptly, 1/(CBx100kΩ) ≦ 1/(CI*(RI+RF)). Where 100kΩ is the output impedance of the mid-rail generator, CB is the mid-rail bypass capacitor, CI is the input coupling capacitor, RI is the input impedance, RF is the gain setting impedance which is on the feedback path. CB is the most important capacitor. Besides it is used to reduce the popping, CB can also determine the rate at which the amplifier starts up during startup or recovery from shutdown mode. De-popping circuitry of G1426 is shown on Figure 2. The PNP transistor limits the voltage drop across the 225kΩ by slewing the internal node slowly when power is applied. At start-up, the voltage at BYPASS capacitor is 0. The PNP is ON to pull the mid-point of the bias circuit down. So the capacitor sees a lower effective voltage, and thus the charging is slower. This appears as a linear ramp (while the PNP transistor is conducting), followed by the expected exponential ramp of an R-C circuit. VDD Vo(PP) VDD RL 2xVo(PP) -Vo(PP) VDD Figure 1 Vo(PP)+VDD/2 RL SHUTDOWN Mode Operations G1426 implements the shutdown mode operations to reduce supply current, IDD, to the absolute minimum level during nonuse periods for battery-power conservation. When the shutdown pin (pin 1) is pulled high, all linear amplifiers will be deactivated to mute the amplifier outputs. And G1426 enters an extra low current consumption state, IDD is smaller than 2µA. Shutdown pin should never be left unconnected, this floating condition will cause the amplifier operations unpredictable. VDD/2 Vo(PP) VDD/2 Figure 2 TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.0 Dec 04, 2003 11 G1426 Global Mixed-mode Technology Inc. Package Information C D L E1 E θ A2 A A1 e y b TSSOP-20L Package NOTE: 1. Package body sizes exclude mold flash protrusions or gate burrs 2. Tolerance ±0.1mm unless otherwise specified 3. Coplanarity : 0.1mm 4. Controlling dimension is millimeter. Converted inch dimensions are not necessarily exact. 5. Follow JEDEC MO-153 SYMBOL A A1 A2 b C D E E1 e L y θ MIN. DIMENSION IN MM NOM. MAX. MIN. ----0.05 0.80 0.19 0.09 6.40 ----4.30 ----0.45 ----0° --------1.00 --------6.50 6.40 4.40 0.65 0.60 --------- 1.20 0.15 1.05 0.30 0.20 6.60 ----4.50 ----0.75 0.10 8° ----0.002 0.031 0.007 0.004 0.252 ----0.169 ----0.018 ----0° DIMENSION IN INCH NOM. --------0.039 --------0.256 0.252 0.173 0.026 0.024 --------- MAX. 0.048 0.006 0.041 0.012 0.008 0.260 ----0.177 ----0.030 0.004 8° TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.0 Dec 04, 2003 12 G1426 Global Mixed-mode Technology Inc. C D L D1 E2 E1 E Note 5 θ A2 A A1 e y b TSSOP-20L (FD) Package NOTE: 1. Package body sizes exclude mold flash protrusions or gate burrs 2. Tolerance ±0.1mm unless otherwise specified 3. Coplanarity : 0.1mm 4. Controlling dimension is millimeter. Converted inch dimensions are not necessarily exact. 5. Die pad exposure size is according to lead frame design. 6. Follow JEDEC MO-153 SYMBOL A A1 A2 b C D E E1 e L y θ D1 E2 MIN. DIMENSION IN MM NOM. MAX. MIN. 0.80 0.00 0.80 0.19 0.09 6.40 ----4.30 ----0.45 ----0° 3.90 2.30 --------1.00 --------6.50 6.40 4.40 0.65 0.60 ----------------- 1.15 0.10 1.05 0.30 0.20 6.60 ----4.50 ----0.75 0.10 8° 4.28 2.78 0.031 0.000 0.031 0.007 0.004 0.252 ----0.169 ----0.018 ----0° 0.153 0.091 DIMENSION IN INCH NOM. --------0.039 --------0.256 0.252 0.173 0.026 0.024 ----------------- MAX. 0.045 0.004 0.041 0.012 0.008 0.260 ----0.177 ----0.030 0.004 8° 0.168 0.109 Taping Specification Feed Direction Typical TSSOP Package Orientation GMT Inc. does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and GMT Inc. reserves the right at any time without notice to change said circuitry and specifications. TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.0 Dec 04, 2003 13