PT2303 2W x 2 Class AB Audio Power Amplifier DESCRIPTION The PT2303 is a power amplifier utilizing CMOS Technology specially designed for audio purpose. It can deliver 2W × 2 power output to the 5V power voltage. The power consumption is very low in stand-by. Total harmonic distortion is lower than 0.03%. The output mode can be switched between the SE (Single-Ended) or BTL (Bridge-Tied Load) mode. Built-in over-temperature protection, package size is not occupies PCB space. It is suitable for small or portable products. FEATURES • • • • • • CMOS Technology Stereo input Output power 2W × 2 (4Ω) Low harmonics distortion (0.03%) SE and BTL modes operation Suppress the pop and click noise when mode changed • Shutdown function, turn on can into save mode (Icc<0.5µA) • Built-in overheat protect APPLICATIONS • • • • LCD monitor (for TV) Portable audio Multimedia speakers Other audio applications BLOCK DIAGRAM Tel: 886-66296288‧Fax: 886-29174598‧ http://www.princeton.com.tw‧2F, 233-1, Baociao Road, Sindian, Taipei 23145, Taiwan PT2303 APPLICATION CIRCUIT CH1 IN VDD Ri Rf 20k 6 -IN1 8 +IN1 1 Shut Down 4,13 VDD 1uF 20k ON OFF ShutDown VDD CVDD 10uF CH2 IN 10 CB 1uF 1k POWER BLOCK +OUT1 AMP1P BTL/SE Sense VDD 3 100k GND 11 -IN2 9 +IN2 20k 220uF 5 Vref 2,7,15 1uF Ri -OUT1 AMP1N SE/BTL HP-IN 100k -OUT2 AMP2N 16 12 220uF Rf 20k AMP2P +OUT2 HEADPHONE 1k 14 ORDER INFORMATION Valid Part Number PT2303-D PT2303-S PT2303-TX PT2303-HT V1.3 Package Type 16 Pins, DIP, 300mil 16 Pins, SOP, 300mil 20 Pins, TSSOP, 173mil 20 Pins, HTSSOP,173mil 2 Top Code PT2303-D PT2303-S PT2303-TX PT2303-HT December 2010 PT2303 PIN CONFIGURATION 16 PINS FOR PT2303-D AND PT2303-S 20 PINS FOR PT2303-TX AND PT2303-HT PIN DESCRIPTION Pin Name I/O Shutdown I GND +OUT1 VDD -OUT1 -IN1 GND +IN1 +IN2 Vref -IN2 -OUT2 VDD +OUT2 GND O O I I I I I O O - HP-IN I NC - V1.3 Description Shutdown pin Entire IC into the shutdown mode when this pin connected to the Vcc Ground Channel 1 output (+) Supply voltage input Channel 1 output (-) Channel 1 input (-) Ground Channel 1 input (+) Channel 2 input (+) Bias reference bypassing Channel 2 input (-) Channel 2 output (-) Supply voltage input Channel 2 output (+) Ground Output mode select, connected to the VDD for SE mode or GND for BTL mode No Connect 3 Pin No. 16 Pins 20 Pins 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 2 3 4 5 6 7 8 13 14 15 16 17 18 19 16 20 - 9 ~ 12 December 2010 PT2303 FUNCTION DESCRIPTION POWER SUPPLY The operating voltage of PT2303 is from 3V to 5V, In general operation 5V is recommended, it can deliver higher power output. When the supply voltage less then 3V the IC can work properly, but the distortion will rise. After the supply voltage exceed 6V the temperature of package outside will rising quickly due to higher stand-by current consumption. SHUTDOWN When the supply still powered the chip, pull-up the shutdown pin to VDD level will take chip into the shutdown mode. After the shutdown mode is active, the total current consumption is less than 0.5µA and the all of input or output pins no voltage output. When shutdown pin set to GND, the IC is back to the normal operation. Shutdown Pin VDD GND Output State Shutdown ON Normal VOLTAGE GAIN ADJUST The output stage structure of the PT2303 is Bridge Tied Loaded (BTL), the close loop voltage gain can be get from following formula. Gain=20log ( Rf ÷ Ri ) + 6dB The close loop gain can be adjusted by external resistance, in general purpose the 6dB gain setting is recommended, please reference to the application circuit. If the amplitude of input voltage in lower level (ex. <2Vpp), it can raise the voltage gain to get enough power output. Recommended of the minimum series resistance (Ri) is 10KΩ to ensure IC have appropriate input impedance. Please refer to following table. External Resistance Ri Rf Gain=0dB 20KΩ 10KΩ Gain=6dB 20KΩ 20KΩ Gain=12dB 10KΩ 20KΩ If the amplitude of input signal exceed the VDD-GND range, or voltage gain setup too high, the input stage is very easy overload and distorted. Please make sure the amplitude of audio source (Vin) and setting the best gain value, in general use the gain setup to +6dB is recommended. Please refer to following table. Operating Voltage VDD=3V VDD=5V Gain=0dB Vin<5Vpp Vin<8Vpp Gain=6dB Vin<2.5Vpp Vin<4Vpp Gain=12dB Vin<1.25Vpp Vin<2Vpp SE/BTL MODE SWITCHING PT2303 have two output modes, SE (Single-Ended) or BTL (Bridge-Tied Load). When driving a 4Ω speaker load suggestion set to the BTL mode for get the more power output. And driving a 32Ω headphone load, it can be set to SE mode and turn-off the un-work amplifier to decrease stand-by power consumption. Switching between the SE/BTL modes is controlled by the HP-IN pin, please refer to following table: HP-IN VDD GND V1.3 Output Mode SE BTL 4 December 2010 PT2303 OVER TEMPERATURE PROTECTION The PT2303 has a built-in over temperature protection circuit, it will turn off all output when the chip temperature over 130℃, the chip will return to normal operation automatically after the temperature cool down to 100℃. POP AND CLICK SURPRESS A power amplifier uses single supply voltage may almost have inrush noise on output in the power-on/off period. It is because of the output DC potential needs time to stable on 1/2VDD, the period relative with the capacitance (CB) on the Vref pin. Larger CB value will extend the stable time, and also can suppress the noise happened in power-on. In supply voltage=5V and CB=2.2µF, stable time is about 300mS. The value of CB also relative with the value of the DC blocking capacitor connected in input terminal. In general condition the time constant of DC blocking capacitor should be less than CB stable time. The recommended value of DC blocking capacitor is 1µF, and the capacitor of output terminal connected to 32Ω headphone is 220µF. Smaller capacitance can shorten the charge time to suppress the pop noise, both the input and output capacitance will limited the low frequency extend range. HEAT DISSIPATION In normal operating, PT2303 needs at least 2 sq inch PCB for heat dissipate; it should be use whole copper foil to cover on it for enough heat dissipation space. We suggest using two-layer PCB for better heat dissipation. The track connected to the output and power pin of IC should be as thick as possible for better heat dissipation ability. If IC doesn’t have enough heat dissipation space (>1 sq inch), and IC is always in full power output situation, an additional heat sink should placed on the chip. V1.3 5 December 2010 PT2303 ABSOLUTE MAXIMUM RATINGS Parameter Supply voltage Operating temperature Storage temperature Maximum input voltage Maximum input current Symbol VDD Topr Tstg Vimax Iimax Condition See Note Min. 0 -40 -65 -0.3 -10 Max. 7 +85 +150 Vcc+0.3 +10 Unit V ℃ ℃ V mA Note: Input pins surge current can be reached 100mA will not induce the CMOS latched up. ELECTRICAL CHARACTERISTICS (Unless otherwise specified, VDD=5V, bandwidth=22~22KHz) Parameter Symbol Condition Supply voltage VDD SE Mode Operating current Is BTL Mode Shutdown=ON Two channels gain error Gerr Ri=Rf=20KΩ Po=0.2W, RL=4Ω THD+N THD Po=1W, RL=4Ω Po=50mW, RL=32Ω THD=1%, RL=8Ω THD=10%, RL=8Ω BTL THD=1%, RL=4Ω Power output Po THD=10%, RL=4Ω THD=1%, RL=32Ω SE THD=10%, RL=32Ω Signal-to-Noise SNR A-Weighted Residual noise Vno A-weighted Output offset Voff +OUT ~ -OUT BTL Channel separation CS F=1KHz SE BTL Power Signal-to-Noise repel rate PSRR F=100Hz SE Overheat close Temperature protect TH Back to work Shutdown ON VDD=3~5V Shutdown voltage VSD Shutdown OFF Shutdown pin SE SE/BTL voltage VSB VDD=3~5V BTL V1.3 6 Min. 3 4 6 0.1 -1 0.03 0.06 0.03 1.0 1.2 1.4 1.8 80 100 95 2 80 80 60 40 85 0.45 0.75 - Typ. 5 6 8 0.5 0 0.05 0.08 0.05 1.1 1.4 1.6 2.0 85 110 100 35 10 90 85 70 45 130 100 0.6 0.15 0.8 0.2 Max. 6 10 12 1 +1 0.07 0.15 0.08 1.2 1.6 1.8 2.1 90 120 50 30 100 95 80 50 140 0.2 0.3 Unit V mA µA dB % W mW dB µV mV dB dB ℃ VDD VDD December 2010 PT2303 PACKAGE THERMAL CHARACTERISTICS PACKAGE TYPE: SOP16L, 300MIL(PT2303-S) Parameter From chip conjunction dissipation to external environment From chip conjunction dissipation to package surface Symbol θJA θJC Condition Ta=25℃ Value 88.8 26 Unit ℃/W ℃/W Value 73 50.7 Unit ℃/W ℃/W Value 90 20 Unit ℃/W ℃/W PACKAGE TYPE: TSSOP20L, 173MIL(PT2303-TX) Parameter From chip conjunction dissipation to external environment From chip conjunction dissipation to package surface Symbol θJA θJC Condition Ta=25℃ PACKAGE TYPE: HTSSOP20L, 173MIL(PT2303-HT) Parameter From chip conjunction dissipation to external environment From chip conjunction dissipation to package surface V1.3 7 Symbol θJA θJC Condition Ta=25℃ December 2010 PT2303 PACKAGE INFORMATION 16 PINS, DIP, 300MIL Symbol A A1 A2 b c e D E E1 L Min. 0.38 2.92 0.36 0.20 Typ. 3.30 2.54 BSC. 19.17 7.62 BSC. 7.87 - 18.67 7.63 2.92 Max. 5.33 4.95 0.56 0.36 19.69 8.26 3.81 Notes: 1. Refer to JEDEC MS-001 BB 2. Unit: mm V1.3 8 December 2010 PT2303 16 PINS, SOP, 300MIL Symbol A A1 A2 b c e D E E1 L θ Min. 0.10 2.05 0.31 0.20 Typ. 1.27 BSC. 10.30 10.30 BSC. 7.5 BSC. - 0.40 0° Max. 2.65 0.30 0.51 0.33 1.27 8° Notes: 1. Refer to JEDEC MS-013 AA 2. Unit: mm V1.3 9 December 2010 PT2303 20PINS, TSSOP, 173MIL Symbol A A1 A2 b c D e E E1 L L1 θ Min. 0.05 0.80 0.19 0.09 6.40 Typ. 1.00 6.50 0.65 BSC. 6.40 BSC. 4.40 0.60 1.0 REF. - 4.30 0.45 0° Max. 1.20 0.15 1.05 0.30 0.20 6.60 4.50 0.75 8° Notes: 1. Refer to JEDEC MO-153 AC 2. Unit: mm V1.3 10 December 2010 PT2303 20PINS, HTSSOP, 173MIL Symbol A A1 A2 b c D D1 e E E1 E2 L L1 θ Min. 0.05 0.80 0.19 0.09 6.40 2.20 4.30 1.50 0.45 0° Typ. 1.00 6.50 0.65 BSC. 6.40 BSC. 4.40 0.60 1.0 REF. - Max. 1.20 0.15 1.05 0.30 0.20 6.60 - Typ. 3.99 2.80 Max. 4.19 3.00 4.50 0.75 8° Notes: 1. Refer to JEDEC MO-153 ACT 2. Unit: mm Option 1 Symbol D1 E2 V1.3 Min. 3.79 2.60 11 December 2010 PT2303 IMPORTANT NOTICE Princeton Technology Corporation (PTC) reserves the right to make corrections, modifications, enhancements, improvements, and other changes to its products and to discontinue any product without notice at any time. PTC cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a PTC product. No circuit patent licenses are implied. Princeton Technology Corp. 2F, 233-1, Baociao Road, Sindian, Taipei 23145, Taiwan Tel: 886-2-66296288 Fax: 886-2-29174598 http://www.princeton.com.tw V1.3 12 December 2010