TA8233BH TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic TA8233BH 30W BTL × 2ch Audio Power Amplifier The thermal resistance θj−T of TA8233BH package designed for low thermal resistance, has high efficiency of heat radiation. The temperature rise of chip can be reduced, and the influence from the degradation of the features due to the temperature rise at the high output can also be reduced. This stereo audio power IC, designed for car audio use, has two built−in channels to reduce the characteristic difference between L and R channels. It also contains output short detection circuit, output clip detection and various kind of protection. Features · Weight: 9.8g (typ.) High power : POUT (1) = 30W (typ.) / channel (VCC = 14.4V, f = 1kHz, THD = 10%, RL = 2Ω) POUT (2) = 26W (typ.) / channel (VCC = 13.2V, f = 1kHz, THD = 10%, RL = 2Ω) POUT (3) = 19W (typ.) / channel (VCC = 13.2V, f = 1kHz, THD = 10%, RL = 4Ω) · Low thermal resistance: θj−T = 1.5°C / W (infinite heat sink) · Low distortion ratio: THD = 0.04% (typ.) (VCC = 13.2V, f = 1kHz, POUT = 1W, RL = 4Ω, GV = 50dB) · Low noise: VNO = 0.30mVrms (typ.) (VCC = 13.2V, RL = 4Ω, GV = 50dB, Rg = 0Ω, BW = 20Hz~20kHz) · Built−in stand−by function : (with pin(4) set at low, power is turned off.) ISB = 1µA (typ.) · Built−in output clip detection circuit : (pin(1): Open collector (active low)) · Built−in output short detection circuit : (pin(9): Open collector (active low)) · Built−in various protection circuits : Thermal shut down, Over voltage, Out→VCC short, Out→GND short and Out−Out short. · Operating supply voltage: VCC (opr) = 9~18V 1 2002-10-30 TA8233BH Block Diagram TA8233BH (GV = 50dB) Caution And Application Method (description is made only on the single channel.) 1. Voltage gain adjustment This IC has the amplifier constructions as shown in Fig.1. The pre-amp (amp 1) is provided to the primary stage, and the input voltage is amplified by the flat amps, amp 3 and amp 4 of each channel through the phase amp (amp 2). Since the input offset is prevented by pre-amp when VCC is set to on, this circuit can remarkably reduce the pop noise. 2 2002-10-30 TA8233BH The total closed loop gain GV of this IC can be obtained by expression below when the closed loop voltage gain of amp 1 is GV1. G V1 = 20log R1 + (R f + R2) (dB)L L L (1) R f + R2 The closed loop voltage gain of power amp, amp 3 and amp 4 is fixed at GV3≒GV4 = 20dB. Therefore, the total closed circuit voltage gain GV is obtained through BTL connection by the expression as below. GV = GV1 + GV3 + 6 (dB)………(2) For example, when Rf = 0Ω, GV is obtained by the expressions (1) and (2) as below. GV≒24 + 20 + 6 = 50dB The voltage gain is reduced when Rf is increased. (Fig.2) With the voltage gain reduced, since (1) the oscillation stability is reduced, and (2) the pop noise changes when VCC is set to on, refer to the items 3 and 4. 2. Stand-by SW function By means of controlling pin(4) (stand-by terminal) to high and low, the power supply can be set to on and off. The threshold voltage of pin(4) is set at 2.1V (3VBE), and the power supply current is about 1µA (typ.) at the stand-by state. Control voltage of pin(4): V (SB) Stand-By Power V (SB) (V) On Off 0~2 Off On 3~VCC Adjustage of stand-by SW (1) Since VCC can directly be controlled to on or off by the microcomputer, the switching relay can be omitted. (2) Since the control current is microscopic, the switching relay of small current capacity is satisfactory for switching 3 2002-10-30 TA8233BH 3. Preventive measure against oscillation For preventing the oscillation, it is advisable to use C4, the condenser of polyester film having small characteristic fluctuation of the temperature and the frequency. The condenser (C6) between input and GND is effective for preventing oscillation which is generated with a feedback signal from a output stage. The resistance R to be series applied to C4 is effective for phase correction of high frequency, and improves the oscillation allowance. (1) Voltage gain to be used (GV setting) (2) Capacity value of condenser (3) Kind of condenser (4) Layout of printed board In case of its use with the voltage gain GV reduced or with the feedback amount increased, care must be taken because the phase-inversion is caused by the high frequency resulting in making the oscillation liable generated. 4. Adjustment of output offset (when the power supply turn on) As this IC is constructed with DC circuit on the pre-amp stage, it is necessary to lower a input offset or output offset by agreement with the each leading edge time constant of the input voltage in the pre-amp stage and NF terminal voltage. Concretely, monitor the output DC voltage and vary the capacity value in input condenser and NF condenser (see Fig.4) (Reference) In case of setting the condition (GV = 40dB) with Rf = 470Ω 4 2002-10-30 TA8233BH 5. Output clip detection function (pin(1)) The output clip detection terminal of pin(1) has the open collector output structure on chip as shown in Fig.5. In case that the output waveform is clipping, the clip detection circuit is operated and NPN Tr. is turned on. It is possible to improve the tone quality with the current of flowing into pin(1) and with controlling the volume, tone control circuit through L.P.F smoothing circuit as shown in Fig.5. In case of being unused this function, use this IC as open connection on pin(1). (Application) 5 2002-10-30 TA8233BH 6. Output to VCC, output to gnd short detection function (pin(9)) The output short detection terminal of pin(9) has open collector output structure on chip as shown in Fig.6. In unusual case that output terminal of power amp. Is condition of output to VCC or output to GND short, it is possible to protect all the system of apparatus as well as power IC protection. In case of being unused this function, use this IC as open-connection on pin(9). (Application) 7. Rapid ripple discharging circuit at the time of VCC off This circuit is effective in such a mode where the VCC and the stand-by terminals become high or low simultaneously; for instance, for a pop noise produced when the power is turned on or off repeatedly by operating the ignition key. When VCC is off, this detection circuit detect VCC≒8V internally on IC. (1) The power stage bias circuit is cut. (2) pin(8): Ripple capacitor is rapidly discharged by turning Q3 on and then Q1 and Q2 on. 6 2002-10-30 TA8233BH (Precaution 1) When the stand-by terminal was put to the low level after the ripple rapid discharging circuit was operated (VCC≒8V) at the time when VCC was turned off, a pop noise may be generated. Therefore, VCC which makes the stand-by terminal low shall be set at 8V or above so that (1) the stand-by terminal is put at the low level and (2) the ripple rapid discharging circuit is turned on when VCC is turned off (in order of (1) and (2)). An example of application is shown in Fig.9. (Precaution 2) If the falling time constant of the VCC line is large (the fall is gentle), the pop noise may become worse. In this case, it is possible to prevent the pop noise from becoming worse by reducing the ability of “ripple rapid discharging circuit at the time of VCC off” according to the increase of the capacity of ripple capacitor of pin(8). However, it shall be kept in mind that the time for turning the power on becomes longer as the result of this method. 8. External part list and description Symbol Recommended Value C1 4.7µF Feature DC blocking Influence Smaller Than Larger Than Recommended Value Recommended Value Related to pop noise at VCC→on. Remarks Related to gain. Refer to item 4. Related to pop noise at VCC→on. C2 47µF Feedback condenser C3 220µF Ripple reduction C4 0.12µF Determination of low cut-off frequency 1 C2 = 2p × fL × R f Time constant is small at VCC→on or off. Time constant is large at VCC→on or off. Oscillation prevention Made liable to oscillate. Oscillation allowance C5 1000µF Ripple filter For filtering power supply hum and ripple. Large at using AC rectified power supply. Small at using DC power supply. C6 1000pF Oscillation prevention Oscillation allowance improved. Noise reduction 7 Refer to item 3. Refer to item 3. 2002-10-30 TA8233BH Maximum Ratings (Ta = 25°C) Characteristic Symbol Rating Unit VCC (surge) 50 V DC supply voltage VCC (DC) 25 V Operating supply voltage VCC (opr) 18 V Output current (peak) Peak supply voltage (0.2s) IO (peak) 9 A Power dissipation PD 50 W Operating temperature Topr -30~85 °C Storage temperature Tstg -55~150 °C Electrical Characteristics (unless otherwise specified, VCC = 13.2V, RL = 4Ω, f = 1kHz, Ta = 25°C) Characteristic Symbol Test Circuit ICCQ — POUT (1) Min. Typ. Max. Unit VIN = 0 — 120 250 mA — VCC = 14.4V, RL = 2Ω THD = 10% — 30 — POUT (2) — RL = 2Ω, THD = 10% 17 26 — POUT (3) — THD = 10% 16 19 — THD — POUT = 1W — 0.04 0.4 % GV — — 48 50 52 dB Voltage gain ratio ∆GV — — -1.0 0 1.0 dB Output noise voltage VNO — Rg = 0Ω, BW = 20Hz~20kHz — 0.3 0.7 mVrms Ripple rejection ratio R.R. — fripple = 100Hz, Rg = 600Ω 40 54 — dB Input resistance RIN — — 30 — kΩ Voffset — -100 0 100 mV Current at stand-by state ISB — — 1 10 µA Cross talk C.T. — Rg = 600Ω VOUT = 0.775Vrms (0dBm) — 60 — dB Pin(4) control voltage VSB — Stand-by→off (power→on) 2.5 — VCC V Pin(1) (clip DET) saturation voltage Vsat (1) — IC = 1mA — 100 — mV Pin(9) (short DET) saturation voltage Vsat (9) — IC = 1mA — 100 — mV Quiescent supply current Output power Total harmonic distortion ratio Voltage gain Output offset voltage Test Condition — VIN = 0 — W Vsat (1), Vsat (9) Test Circuit 8 2002-10-30 TA8233BH Test Circuit TA8233BH (GV = 50dB) 9 2002-10-30 TA8233BH 10 2002-10-30 TA8233BH 11 2002-10-30 TA8233BH 12 2002-10-30 TA8233BH Package Dimensions Weight: 9.8g (typ.) 13 2002-10-30 TA8233BH RESTRICTIONS ON PRODUCT USE 000707EBF · 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. · This product generates heat during normal operation. However, substandard performance or malfunction may cause the product and its peripherals to reach abnormally high temperatures. The product is often the final stage (the external output stage) of a circuit. Substandard performance or malfunction of the destination device to which the circuit supplies output may cause damage to the circuit or to the product. · · · 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. 14 2002-10-30