TA2131FN TOSHIBA Bipolar Linear IC Silicon Monolithic TA2131FN Low Current Consumption Headphone Amplifier for Portable MD Player (With Bass Boost Function) The TA2131FN is a low current consumption headphone amplifier developed for portable digital audio. It is particularly well suited to portable MD players that are driven by a single dry cell. It also features a built-in bass boost function with AGC, and is capable of bass amplification of DAC output and analog signals such as tuner. Features · Low current consumption: ICCQ (VCC1) = 0.55 mA (typ.) ICCQ (VCC2) = 0.20 mA (typ.) · Output power: Po = 8 mW (typ.) · Low noise: Vno = −102dBV (typ.) · Built-in low-pass boost (with AGC) · I/O pin for beep sound · Outstanding ripple rejection ratio · Built-in power mute · Built-in power ON/OFF switch · Operating supply voltage range (Ta = 25°C): VCC1 = 1.8~4.5 V Weight: 0.14 g (typ.) (VCC1 = 2.8 V, VCC2 = 1.2 V, f = 1 kHz, THD = 10%, RL = 16 Ω) VCC2 = 0.9~4.5 V 1 2002-04-19 TA2131FN Block Diagram Vref VCC1 BEEP Vref OFF 24 Vref IN Vref LPF1 23 22 BST BEEP GND IN SW 21 20 19 18 MT SW PW SW 17 MT TC 16 BEEP BOOST MUTE SW SW Vref (2.8 V) OFF ON OFF ON ON BST NF1 DAC OUT VCC1 VCC1 15 14 INB 13 Vref PW SW BST1 BST2 LPF2 1 BST NF2 2 BST OUT PW B BST AGC 3 AGC IN 4 DET 5 OUTB 6 PWR GND RL Vref 7 PW A OUTA 8 VCC2 9 BEEP OUTA 10 BEEP OUTB 11 INA 12 Vref RL +B (1.2 V) Vref 2 DAC OUT 2002-04-19 TA2131FN Terminal Explanation (Terminal voltage: Typical terminal voltage at no signal with test circuit, VCC1 = 2.8 V, VCC2 = 1.2 V, Ta = 25°C) 1 LPF2 Terminal Explanation BST amplifier 1 output (filter terminal) Terminal Voltage (V) Internal Circuit 12 AGC PWA BST1 ADD 20 kW 23 LPF1 ADD amplifier output (filter terminal) 13 0.61 PWB 30 kW 2 kW 23 0.61 BST2 AMP 12 kW 10 kW 20 kW 20 kW Terminal No. 24 24 BST NF1 1 BST amplifier 1 NF 0.61 0.61 ADD 10 kW 10 kW BST1 OUT OUTB BST2 Power amplifier output OUTA 3 0.61 15 kW INA 6 Power amplifier input 13 10 kW INB 13 20 kW 12 10 kW 20 kW 8 15 kW 10 kW 6 BST OUT 8 20 kW 3 PWA 12 BST amplifier 2 output terminal Vref 10 kW 10 kW BST NF2 20 kW 2 BST amplifier 2 NF terminal (low-pass compensation condenser connection terminal) 20 kW Vref 0.61 PWB 2 3 2002-04-19 TA2131FN Terminal No. Terminal Explanation AGC IN Signal input level to BST amplifier is varied according to the input level to the boost AGC input terminal. Input impedance: 15 kW (typ.) Terminal Voltage (V) Internal Circuit 14 Vref 5 kW 4 0.61 4 10 kW 5.1 kW 14 5 DET Smoothing of boost AGC level detection 7 PWR GND GND of power amplifier output stage ¾ 0 9 VCC2 VCC (+B) at power amplifier output stage ¾ 1.2 10 BEEP OUTA Beep sound output terminal 11 14 BEEP OUTB 19 19 BEEP IN Beep sound input terminal Receives beep sound signals from microcomputer. 14 VCC1 Main VCC ¾ 5 ¾ 10 kW 10 11 0 ¾ 2.8 14 MT TC 12 kW 15 Mute smoothing Power mute switch Reduces the shock noise during switching 1.2 15 4 2002-04-19 TA2131FN Terminal No. Terminal Explanation Terminal Voltage (V) Internal Circuit VCC1 14 16 PW SW Power ON/OFF switch “H” level: IC operation “L” level: IC OFF Refer to function explanation 5 47 kW 16 ¾ VCC1 14 17 MT SW Mute switch “L” level: mute reset “H” level: mute ON Refer to function explanation 5 ¾ 47 kW 17 18 20 BST SW 14 Bass boost ON/OFF switch “H” level/OPEN: BST ON “L” level: BST OFF Refer to function explanation 5 GND GND of input stage in power amplifier Vref IN Reference voltage circuit filter terminal Vref Reference voltage circuit 20 kW ¾ ¾ 0 18 14 0.61 10 kW 4 kW 21 22 21 10 kW 22 0.61 5 2002-04-19 TA2131FN Function Explanation 1. Bass Boost Function 1-1 Description of Operation TA2131FN has a bass boost function for bass sound reproduction built-in to the power amplifier. With the bass boost function, at medium levels and lower, channel A and channel B are added for the low frequency component, and output to BST amplifier 2 (BST2) in negative phase. That signal is inverted and added before being subjected to bass boost. If the signal of the low-frequency component reaches a high level, the boost gain is controlled to main a low distortion (see Fig.1). V (OUT) 20 kW INA 10 kW PWB V (NF1) Vref V (LPF2) V (RL) 220 mF 16 W RL BST NF2 8 1 mF Vref V (NF2) 4 OUTB 220 mF 16 W RL BST OUT LPF2 7 0.1 mF 0.1 mF 9 Vref Figure 1 1-2 20 kW AGC IN BST NF1 6 10 Vref 10 kW 15 kW 22 kW 2 kW DET 5 11 0.1 mF LPF1 10 kW BST AGC 10 kW 30 kW 5 kW 4.7 mF 20 kW INB 21 V (LPF1) 10 kW 15 kW BST2 2 10 kW BST1 20 kW 10 mF PWA 12 kW Vref DAC OUT 10 kW 20 kW 10 kW ADD 10 kW 0.1 mF 10 mF OUTA 20 kW 22 V (BST OUT) System Diagram of Bass Boost AGC Circuit The AGC circuit of the bass boost function detects with “AGC DET” the voltage component created by “BST2,” and as the input level increases, the variable impedance circuit is changed, and the bass boost signal is controlled so that it is not assigned to BST amplifier 1. In this way, the bass signal to “BST2” input is shut-off, and that boost gain is controlled. 1-3 Bass Boost System As shown in Fig.1, the flow of the bass boost signal is that the signal received from power amplifier input goes through LPF1, ADD amplifier, ATT (variable impedance circuit), BPF1 (BST amplifier 1) and LPF2, and the negative phase signal to the power amplifier input signal is output from BST amplifier 2. The reason why it becomes the negative phase of the BST amplifier 2 signal is that the phase is inverted by 180° in the audible bandwidth by the secondary characteristics of LPF1 and LPF2 in Fig.1. Ultimately the main signal and the bass boost signal formed before BST2 are added. Fig.2 shows the frequency characteristics to each terminal. 6 2002-04-19 TA2131FN 40 V (OUT) (dB) 20 V (RL) V (NF2) V (BST OUT) 0 GV V (LPF2) V (NF1) -20 -40 -60 1 V (LPF1) 10 100 f Figure 2 2. 1k 10 k 100 k (Hz) During Bass Boost (Frequency Characteristics to Each Terminal) Low-Pass Compensation 2-1. Function In C-couple type power amplifiers, it is necessary to give the output condenser C a large capacity to flatten out the frequency characteristics to the low frequency band (this is because the loss in the low frequency bandwidth becomes larger due to the effect of the high-pass filter comprising C and RL). Particularly when the headphone load is approximately 16 W and an attempt is being made to achieve frequency characteristics of ±3 dB at 20 Hz, a large capacity condenser of C = 470 mF is required. Bearing this situation in mind, a low-pass compensation function was built in to the TA2131FN, and while reducing the capacity of the output coupling condenser, almost flat (±3 dB) frequency characteristics in all audible bandwidths (20 Hz to 20 kHz) have been achieved. Fig.3 shows the low-pass system diagram, and Fig.4 shows the frequency characteristics at each point. In Fig.4, (a) represents the status lost by the low-pass as a result of the high-pass filter comprising the headphone load (RL = 16 W) and the output coupling condenser (220 mF) in the C-coupling system. V (OUT) 20 kW PWA ADD Vref BST2 10 mF 10 kW 10 kW 15 kW 10 kW 15 kW 13 20 kW INB 8 10 kW 10 kW 10 kW PWB 220 mF 16 W RL BST NF2 2 10 kW DAC OUT V (RL) OUTA 20 kW 10 mF 20 kW INA 12 6 OUTB 1 mF Vref 220 mF 16 W RL 20 kW Figure 3 Low-Pass Compensation System Diagram 7 2002-04-19 TA2131FN 20 (b) (c) 0 GV (dB) 10 (a) -10 -20 1 10 f Figure 4 1k 100 10 k 100 k (Hz) Power Amplifier Frequency Characteristics <Principle of Low-Pass Compensation> The low-pass component alone is extracted from the composite signal of PWA/PWB output, and that frequency signal is fed back to PWA/PWB once more via the inversion amplifier, thereby making it possible to increase the gain only of the low-pass component. The frequency characteristics of the power amplifier output V (OUT) in this state are shown in Fig.4 (b). In practice they are the frequency characteristics (c) viewed from load terminal V (RL), and the low-pass is compensated relative to the state in (a). 2-2. Low-Pass Compensation Condenser and Crosstalk In this low-pass compensation condenser circuit, processing is carried out using the composite signal of power amplifier output, so this affects crosstalk, according to the amount of compensation. f characteristics and crosstalk generated by the capacity of the condenser for compensation (2-pin) are shown below. 10 VCC1 = 2.8 V VCC2 = 1.2 V Response (dB) Rg = 620 W RL = 16 W Filter: LPF 80 kHz C = 0.47 mF Output C = 220 mF 0 Vref short C = 1 mF C = 2.2 mF -10 10 30 100 300 f Figure 5 1k 3k 10 k 30 k (Hz) Condenser and f Characteristics for Low-Pass Compensation 8 2002-04-19 TA2131FN CT – f VCC1 = 2.8 V VCC2 = 1.2 V Rg = 620 W RL = 16 W Vo = -22dBV WIDE BAND Output C = 220 mF 0 CT (dB) C = 0.47 mF -20 C = 1 mF C = 2.2 mF -40 -60 10 Vref short 30 100 300 1k f Figure 6 3. 3k 10 k 30 k 100 k (Hz) Low-Pass Compensation Condenser and Crosstalk Beep Beep sound signals from microcomputer can be received by the beep input terminal (19-pin). The PWA and PWB of the power amplifier during power mute are turned OFF, and the beep signal input from BEEP-IN (19-pin) is output from the BEEP-OUT terminal (10/11-pin) as fixed current, after passing through the converter and current amplification stage. Connecting this terminal to the headphone load outputs the beep sound. If the beep sound is not input, fix the BEEP-IN (19-pin) terminal to GND level. VCC PW SW (18-pin) ON OFF OFF MT SW (17-pin) OFF ON OFF BEEP IN (15-pin) 200 ms 100 ms 100 ms 20 IBEEP 23 15 IBEEP 24 ID 9 2002-04-19 TA2131FN 4. Power Switch As long as the power switch is not connected to “H” level, the IC does not operate. If it malfunctions due to external noise, however, it is recommended to connect a pull-down resistor externally (the power switch is set to be highly sensitive). 5. Threshold Voltages of Switches (1) PW SW (2) (V) 4.5 V Terminal voltage V17, V18 Terminal voltage V16 (V) 4.5 V 4 H 3 2 1.6 V 1 4 3 H 2 1 0.8 V 0.6 V L 0 MT SW, BST SW 5 5 1 2 0.3 V 3 Power supply voltage VCC 4 5 (V) 0 1 L 2 3 4 Power supply voltage VCC PW SW (V16) 5 (V) MT SW (V17) “H” level IC operation “H” level Mute ON “L” level IC OFF “L” level Mute reset BST SW (V18) 6. “H” level/OPEN BST ON “L” level BST OFF These capacitors which prevent oscillation of the power amplifier, and are between the Vref and VCC-GND must have a small temperature coefficient and outstanding frequency characteristics. 10 2002-04-19 TA2131FN Maximum Ratings Characteristic Symbol Rating Unit Supply voltage VCC 4.5 V Output current Io (peak) 100 mA Power dissipation PD (Note) 500 mW Operating temperature Topr -25~75 °C Storage temperature Tstg -55~150 °C Note: Derated above Ta = 25°C in the proportion of 4 mW/°C. Electrical Characteristics (Unless specified otherwise, VCC1 = 2.8 V, VCC2 = 1.2 V, Rg = 600 W, RL = 16 W, f = 1 kHz, Ta = 25°C) Characteristic Quiescent supply current Power supply current during drive Test condition Min Typ. Max Unit ICC1 IC OFF (VCC1), SW1: b, SW2: b ¾ 0.1 5 ICC2 IC OFF (VCC2), SW1: b, SW2: b ¾ 0.1 5 ICC3 MUTE ON (VCC1), SW1: a, SW2: b ¾ 0.35 0.50 mA ICC4 MUTE ON (VCC2), SW1: a, SW2: b ¾ 5 10 mA ICC5 No signal (VCC1), SW1: a, SW2: a ¾ 0.55 0.75 ICC6 No signal (VCC2), SW1: a, SW2: a ¾ 0.20 0.40 ICC7 Po = 0.5 mW + 0.5 mW output (VCC1) ¾ 0.6 ¾ ICC8 Po = 0.5 mW + 0.5 mW output (VCC2) ¾ 5.3 ¾ Gain GV Vo = -22dBV 10 12 14 Channel balance CB Vo = -22dBV -1.5 0 1.5 mA mA dB Pomax THD = 10% 5 8 ¾ mW Total harmonic distortion THD Po = 1 mW ¾ 0.1 0.3 % Output noise voltage Vno Rg = 600 W, Filter: IHF-A, SW4: b ¾ -102 -96 dBV Crosstalk CT Vo = -22dBV -42 -48 ¾ RR1 fr = 100 Hz, Vr = -20dBV inflow to VCC2 -71 -77 ¾ RR2 fr = 100 Hz, Vr = -20dBV inflow to VCC1 -54 -64 ¾ ATT Vo = -12dBV, SW2: a ® b -90 -100 ¾ VBEEP V Beep IN = 2 Vp-o, SW2: b -53 -48 -43 Output power Power Section Symbol Ripple rejection ratio Mute attenuation Beep sound output voltage Boost gain dB BST1 Vo = -20dBV, f = 100 Hz, SW3: ON ® OPEN 1 4 7 BST2 Vo = -30dBV, f = 100 Hz, SW3: ON ® OPEN 10 13 16 BST3 Vo = -50dBV, f = 100 Hz, SW3: ON ® OPEN 13.5 16.5 19.5 11 dBV dB 2002-04-19 TA2131FN Test Circuit Vref 4.7 mF 4.7 mF 0.1 mF 10 mF (a) SW2 OFF SW3 (b) VCC1 (2.8 V) (b) (a) (a) SW4B SW1 (b) 10 mF VCC1 Vref 1 mF Vref 600 W Rg = 600 W ON 24 23 22 21 20 BST NF1 LPF1 Vref Vref IN GND 19 BEEP IN 18 BST SW 17 16 15 14 13 MT SW PW SW MT TC VCC1 INB TA2131FN AGC IN DET OUTB PWR GND OUTA VCC2 BEEP OUTA BEEP OUTB INA 1 2 3 4 5 6 7 8 9 10 11 12 Vref SW4A (a) (b) 600 W 16 W (*) 16 W (*) 220 mF 0.1 mF 22 kW 0.1 mF 10 mF BST OUT 220 mF BST NF2 0.1 mF LPF2 +B (1.2 V) Vref Vref (*) 0.22 mF + 10 W Monolithic ceramic capacitor 12 2002-04-19 TA2131FN Application Circuit 1 100 kW 4.7 mF 10 mF 0.1 mF OFF DAC OUT VCC1 (2.8 V) 10 mF VCC1 BEEP ON OFF ON 1 mF Vref 4.7 mF Vref 0.1 mF Vref 24 23 22 21 20 BST NF1 LPF1 Vref Vref IN GND 19 18 BEEP IN BST SW 17 16 15 14 13 MT SW PW SW MT TC VCC1 INB TA2131FN LPF2 BST NF2 BST OUT AGC IN DET OUTB PWR GND OUTA VCC2 BEEP OUTA BEEP OUTB INA 1 2 3 4 5 6 7 8 9 10 11 12 RL Vref 10 mF (*) 220 mF (*) 220 mF 0.1 mF 0.1 mF 1 mF 0.1 mF Vref 22 kW RL +B (1.2 V) Vref DAC OUT (*) 0.22 mF + 10 W Monolithic ceramic capacitor 13 2002-04-19 TA2131FN Application Circuit 2 (Low-Pass Compensation/Bass Boost Function/Beep Not Used) (2.8 V) ON OFF 1 mF ON 4.7 mF 10 mF OFF DAC OUT VCC1 10 mF VCC1 Vref Vref 24 23 22 21 20 BST NF1 LPF1 Vref Vref IN GND 19 18 BEEP IN BST SW 17 16 15 14 13 MT SW PW SW MT TC VCC1 INB TA2131FN LPF2 BST NF2 BST OUT AGC IN DET OUTB PWR GND OUTA VCC2 BEEP OUTA BEEP OUTB INA 1 2 3 4 5 6 7 8 9 10 11 12 RL Vref Vref 10 mF (*) 220 mF (*) 220 mF Vref RL +B (1.2 V) Vref DAC OUT (*) 0.22 mF + 10 W Monolithic ceramic capacitor 14 2002-04-19 TA2131FN Characteristics (Unless otherwise specified VCC1 = 2.8 V, VCC2 = 1.2 V, Rg = 600 W, f = 1 kHz, Ta = 25°C) VDC – VCC2 1.0 0.8 0.8 0.6 Output voltage (V) Quiescent supply current ICC (mA) ICC – VCC2 1.0 ICC5 0.4 ICC6 0.2 0 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 0 0.6 2.4 0.8 1.0 1.2 1.4 1.6 Supply voltage VCC2 MUTE ON 1.8 2.0 2.2 (V) Po – VCC2 100 0.8 30 (mW) 1.0 ICC (mA) 0.4 (V) ICC – VCC2 10 Output volatage Po Quiescent supply current 0.6 0.2 Supply voltage VCC2 0.6 0.4 ICC3 0.2 3 1 0.3 THD = 10 % ICC4 0 0.6 0.8 1.0 1.2 1.4 1.6 A/Bch IN 1.8 Supply voltage VCC2 2.0 2.2 0.1 0.6 2.4 0.8 (V) 1.0 1.2 (dBV) Vno ICC8 Output noise voltage ICC Consumption supply current 2.0 2.2 2.4 (V) IHF-A 3 1 ICC7 0.3 0.1 0.01 1.8 Vno – VCC2 A/Bch IN 10 1.6 -80 100 30 1.4 Supply voltage VCC2 ICC – Po (mA) (Vref, OUT) 0.03 0.1 0.3 1 Output voltage Po 3 10 -85 -90 -95 -100 -105 -110 -115 -120 0.6 30 (mW) 0.8 1.0 1.2 1.4 1.6 1.8 Supply voltage VCC2 15 2.0 2.2 2.4 (V) 2002-04-19 TA2131FN THD – Po R.R. – VCC2 10 inflow to VCC1 0 Ripple rejection ratio R.R. (dB) Total harmonic distortion THD (%) fr = 100 Hz 3 1 0.3 10 kHz 0.1 100 Hz/1 kHz 0.03 0.01 0.1 0.3 1 3 10 30 Output voltage Po 100 300 Vr = -20dBV 20 40 60 80 100 0.4 0.8 (mW) 1.2 R.R. – VCC Ripple rejection ratio R.R. (dB) (%) THD Total harmonic distortion 1 0.1 0.03 0.6 10 kHz 1 kHz 0.8 100 Hz 1.0 1.2 1.4 1.6 1.8 Supply voltage VCC2 2.0 2.2 Vr = -20dBV -40 -60 -80 -100 0.4 2.4 (V) 0.8 1.2 (dBV) -40 -20 Beep output voltage (dBV) Output voltage Vo -10 -30 -40 -50 2.4 (V) -50 -60 -70 -80 -90 -60 -100 -70 10 -110 0.1 1k Frequency f 2.0 BEEP -30 300 1.6 Supply voltage VCC2 Vo – f 100 inflow to VCC2 -20 0 30 (V) fr = 100 Hz 3 0.3 2.4 0 RL = 16 W Po = 1 mW A/Bch IN 10 2.0 Supply voltage VCC2 THD – VCC2 30 1.6 3k 10 k 30 k (Hz) fBEEP = 400 Hz Rectangle wave 0.3 0.5 Beep input voltage 16 1 3 VBEEP 5 10 (Vp-o) (V) 2002-04-19 TA2131FN ICC – Ta CT – f 0 1.0 (mA) Vo = -22 dBV Application circuit 1 30 40 (No use Low-Pass Compensation) 50 Application circuit 2 60 70 10 0.8 ICC 20 Quiescent supply current Cross talk CT (dB) 10 30 100 300 1k Frequency f 3k 10 k 0.4 ICC6 0.2 0 -50 30 k (Hz) ICC5 0.6 -25 0 25 50 75 100 Ambient temperature Ta (°C) VDC – Ta Output voltage VDC (V) 1.0 0.8 0.6 0.4 0.2 0 -50 -25 0 25 50 75 100 Ambient temperature Ta (°C) 17 2002-04-19 TA2131FN Package Dimensions Weight: 0.14 g (typ.) 18 2002-04-19 TA2131FN RESTRICTIONS ON PRODUCT USE 000707EBA · TOSHIBA is continually working to improve the quality and reliability of its products. Nevertheless, semiconductor devices in general can malfunction or fail due to their inherent electrical sensitivity and vulnerability to physical stress. It is the responsibility of the buyer, when utilizing TOSHIBA products, to comply with the standards of safety in making a safe design for the entire system, and to avoid situations in which a malfunction or failure of such TOSHIBA products could cause loss of human life, bodily injury or damage to property. In developing your designs, please ensure that TOSHIBA products are used within specified operating ranges as set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the precautions and conditions set forth in the “Handling Guide for Semiconductor Devices,” or “TOSHIBA Semiconductor Reliability Handbook” etc.. · The TOSHIBA products listed in this document are intended for usage in general electronics applications (computer, personal equipment, office equipment, measuring equipment, industrial robotics, domestic appliances, etc.). These TOSHIBA products are neither intended nor warranted for usage in equipment that requires extraordinarily high quality and/or reliability or a malfunction or failure of which may cause loss of human life or bodily injury (“Unintended Usage”). Unintended Usage include atomic energy control instruments, airplane or spaceship instruments, transportation instruments, traffic signal instruments, combustion control instruments, medical instruments, all types of safety devices, etc.. Unintended Usage of TOSHIBA products listed in this document shall be made at the customer’s own risk. · The products described in this document are subject to the foreign exchange and foreign trade laws. · The information contained herein is presented only as a guide for the applications of our products. No responsibility is assumed by TOSHIBA CORPORATION for any infringements of intellectual property or other rights of the third parties which may result from its use. No license is granted by implication or otherwise under any intellectual property or other rights of TOSHIBA CORPORATION or others. · The information contained herein is subject to change without notice. 19 2002-04-19