TDA7336 STEREO PREAMP + AMS + DOLBY B* NOISE REDUCTION PROCESSOR DUAL CHANNEL PROCESSOR FOR PLAYBACK APPLICATIONS. STEREO DOLBY B NR SYSTEM LOW NOISE HEAD PREAMPLIFIER MUTE, AMS (AUDIO MUSIC SENSOR) FUNCTIONS INTERNAL SWITCHES FOR EQUALIZATION DOLBY REFERENCE LEVEL -6dBm (388.2mVRMS) MINIMUM NUMBER OF EXTERNAL COMPONENTS LOW SUPPLY CURRENT (18mA) MIXED BIPOLAR/CMOS TECHNOLOGY DESCRIPTION The TDA7336 is a monolithic BICmos IC designed for use in stereo cassette player systems. The device includes two separate audio channels composed by low noise preamplifier, Dolby B noise reduction system and Audio Music Sensor. The dual preamplifier contains mute, metal/normal facilities for amplification of low level signal in applications requiring very low noise performances. Each channel consists of two cascaded operational amplifiers. The first one, AMP1, has a fixed gain of 36dB, and allows magnetic heads connection directly to ground. The second one, AMP2, is a standard operational amplifier whose equalizing external components fix the frequency response. The Audio Music Sensor circuit detects the interprogram space and then the starting point of musical programs (the interprogram time and program detection time are externally selectable). The device contains Dolby B decoder NR chains requiring very few external components and do not require coils. * Dolby B and the Double-D symbol are trademarks of Dolby Laboratories Licensing Corporation, San Francisco, California 94103-4813, USA. This device is available only to Licensing and application information may be obtained from Dolby Lab. November 1999 SO28 ORDERING NUMBER: TDA7336 PIN CONNECTION (Top view) GND 1 28 EQ.SW INL 2 27 INR EQLI 3 26 EQRI EQLO 4 25 EQRO OUTL 5 24 OUTR DINL 6 23 DINR AMS SW 7 22 GND DIG INTP 8 21 AMSOUT INTS 9 20 AMSGin MUTE 10 19 NR SW TCL 11 18 TCR DOUTL 12 17 DOUTR IREF 13 16 VREF N.C. 14 15 Vs D94AU052 1/20 TDA7336 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit VS Supply Voltage 12 V Ptot Total Power Dissipation 1 W Top Operating Temperature Range -40 to 85 °C Tstg Storage Temperature Range -40 to 150 °C 85 °C/W THERMAL DATA Rth j-pins Thermal resistance junction-pins PIN FUNCTIONS N. Name 1 GND VDC (V) Function Ground 2 IN L 0 3,26 EQLI, EQRI 4.6 Equalizer Inputs 4, 25 EQLO, EQRO 4.6 Equalizer Outputs 5, 24 OUTL, OUTR 4.6 Preamplifier Outputs 6, 23 DINL, DINR Vref Dolby NR Inputs 7 AMS SW 5.6 Audio Music Sensor Switch (ON/OFF) HIGH = ON 8 INTP Interprogram Time Constant (”Signal Detection”) Interspace Time Constant (”Blank Detection”) 9 INTS 10 MUTE 11, 18 TLC, TCR 12, 17 DOUTL, DOUTR 13 Iref 15 VS 16 Vref 19 NR SW 20 AMS GIN 21 AMS OUT 22 GND DIG. Preamplifier Left Input Mute Switch ON = LOW (2) 0.4 Dolby Time Constants Vref Dolby Outputs 1.2 Reference Current Source Positive Power Supply VS/2 Reference Voltage Noise reduction ON/OFF: HIGH =OFF (2) 1.4 Audio Music Sensor Input Pin Audio Music Sensor Output Pin (open collector configuration, see Fig. 2) 0 Digital Ground 27 IN R 0 Preamplifier Right Input 28 EQ SW 0 Equalizer Switch (Low = normal position High = metal position) (2) Internal pull-up resistor (digital high level if pin left open) 2/20 INPUT L INPUT R INL INR 36dB 3 1.2K 1K EQLI 6.8K R3 R4 300K 4 RM AMP2 AMP1 R1 36dB AMP2 RM 25 R6 AMP1 TR1 2 27 26 EQRI 300K R5 (*) Capacitor tolerance is ±10% 1µF C1 1µF C2 R2 0.68µF C20 10nF C3 EQLO 28 5 RN 1.2K R14 30K 100nF C15 Vs GND 0.33µF C5(*) DINL 7 20 24 6 DINR R8 10K OUTR 23 0.33µF C6(*) RN 1.2K EQRO 10nF C4 OUTL TR2 EQ SW 6.8K 470K R7 8 22 INTP AMS AMSGin 0.22µF C8 AMSSW 1.2K INTS 9 21 Vs 0.1µF C7 C9 1µF 1K Vs 17 18 100K R9 0.68µF (*) C10 C16 100nF C12 4.7µF MUTE 10 BIAS DOUTR 4.7µF C13 D93AU049A OUTL 12 DOUTL 11 TCL DOLBY DOLBY 0.68µF(*) TCR C11 AMSGout R10 100K OUTR GND 1 R15 30K IREF Vs Vs GND R11 43K 0.22µF C18 Vs GND Vs 0.68µF C19 R13 100K 4.7µF C14 VREF NRSW 13 15 16 19 TDA7336 Figure 1: Application Circuit 3/20 TDA7336 Figure 1a: Components& Top Copper Layer of the Fig. 1 (1:1 scale). Figure 1b: Bottom Copper Layer of the Fig. 1 (1:1 scale). 4/20 300pF INPUT L 300pF INPUT R 36dB 2 6.8K 1.8K R4 300K 4 R3 EQLI 3 AMP2 AMP1 RM AMP2 AMP1 RM 25 R6 R1 36dB 27 26 EQRI 300K (*) Capacitor tolerance is ±10% 1µF C1 600 INL 600 INR 1µF C2 R5 GND 10nF C3 5 RN 1.2K 28 EQLO 24 OUTR 7 6 DINL 20 23 100nF C15 0.33µF C5(*) Vs R8 10K DINR 0.33µF C6(*) RN 1.2K EQRO 10nF C4 OUTL R2 EQ SW 470K R7 8 22 INTP AMS AMSGin 0.22µF C8 AMSSW 6.8K INTS 9 21 Vs 0.1µF C7 C9 1µF 1.8K Vs 100K R9 D93AU050A OUTL C10 0.68µF (*) C12 4.7µF 10 MUTE 12 DOUTL BIAS DOUTR 11 DOLBY DOLBY 17 0.68µF(*) TCR 4.7µF C13 TCL 18 C11 AMSGout R10 100K OUTR IREF GND 13 1 Vs 4.7µF C14 VREF 16 15 NRSW 19 Vs R11 43K 0.22µF C18 Vs GND TDA7336 TEST CIRCUIT 5/20 TDA7336 ELECTRICAL CHARACTERISTICS (V S = 8.5V; f = 1KHz; Rg = 600Ω Tamb = 25°C; R11 = 43KΩ all level referenced to -6dBm/400Hz, at D out with NR SW OFF; unless otherwise specified see application circuit of Fig. 1) NAB METAL position. SUPPLY Symbol Min. Typ. Max. VS Supply Voltage Parameter Test Condition 8 8.5 10.5 V IS Supply Current 11 18 26 mA Vref Reference Voltage (pin 16) VDC DC Voltage pin 13 (R11 = 43K) SVR Ripple Rejection (Input Referred) Vripple = 0.3Vrms fripple = 1KHz MUTEth Mute Threshold Pin 10 ON OFF IMUTE MUTEA Dolby OFF Dolby ON 4 4.3 4.6 V 1.15 1.25 1.35 V 80 85 90 95 dB dB 0 2.0 Mute Current 10 Mute Attenuation Unit 55 65 30 50 0.8 VS V V 20 µA dB 70 KΩ 10 µA PREAMPLIFIER RI Input Resistance II Input Bias Current GV Closed Loop Gain (pin 2, 27) pin 3, 4 and 25, 26 shorted 32.5 35.5 38.5 dB 1 dB KΩ ∆GV Closed Loop Gain Match -1 RM Resistance Metal Position 4.35 5.8 7.25 RN Resistance Normal Position 50 160 300 eN Total Input Noise Unw. B= 20Hz to20KHz Rg = 0Ω; R g = 600Ω; A weighted R g = 600Ω; RO Output Impedance (Pin 5, 24) 0.9 1.2 Ω µV µV µV 0.45 0.8 0.5 1.7 KΩ EQl Normal Low Level (pin 28) 0 1.5 V EQh Metal High Level (pin 28) 3.5 VS V ∆R M Metal Resistance Matching –2 0 +2 % 5 mA 200 800 mV 1.1 1.4 KΩ AUDIO MUSIC SENSOR IAMSOUT AMS Output Current VAMSOUT AMS Output Low Level R P20 IAMOUT = 2mA Input Impedance 0.8 AMSswl AMS OFF Low Level 0 0.8 V AMS swh AMS ON High Level 2 VS V VTH1 Interprogram Threshold Voltage (pin 8) 1.2 1.45 1.7 V VTH2 Interspace Threshold Voltage (pin 9) 4 4.3 4.6 V AMS th AMS Threshold Level see note (3) 0.6 1 1.4 V IAMSsw AMS Switch pin Current 5 10 15 µA DOLBY SECTION GV f = 1KHz; Gain Matching RDI Dolby Input Res. (pin 6, 23) S/H Signal Handling VS = 8V; THD = 1% R DO Dolby Output Imp. (pin 12, 17) Decode Out f = 10KHz; V I = 0.4dB B DEC 1 6/20 Voltage Gain ∆GV OFF -1 OFF -0.5 0 1 0.5 dB dB 46 63 KΩ OFF 12 13 dB 100 200 300 Ω ON -1.5 0 1.5 dB TDA7336 ELECTRICAL CHARACTERISTICS (continued) DOLBY SECTION DOLBY Min. Typ. Max. Unit B DEC 2 Symbol Decode Out Parameter f = 500Hz; VI = -22.1dB Test Condition ON -26.5 -25 -23.5 dB B DEC 3 Decode Out f = 2KHz; V I = -18dB ON -26.5 -25 -23.5 dB B DEC 4 Decode Out f = 5KHz; V I = -29.7dB ON -41.5 -40 -38.5 dB B DEC 5 Decode Out f = 10KHz; V I = -29.6dB ON -41.5 -40 -38.5 dB NRl Dolby ON Low Level Pin 19 0 0.8 V NRh Dolby OFF High Level Pin 19 2 VS V GENERAL (PREAMPLIFIER + DOLBY) Symbol THD S/N CS Parameter Test Condition Total Harmonic Dist. Signal to Noise Ratio Channel Separation Typ. Max. Unit VO = 0dB; f = 1KHz Dolby OFF Min. 0.02 0.1 % VO = 0dB; f = 1KHz Dolby ON 0.05 0.1 VO = 0dB; f = 10KHz Dolby OFF 0.03 VO = 0dB; f = 10KHz Dolby ON 0.08 % Rg = 600Ω; VO = 0dB; Unweighted; Dolby OFF 63 dB Rg = 600Ω; VO = 0dB; Unweighted; Dolby ON 70 dB Rg = 600Ω; VO = 0dB; CCIR/ARM; Dolby OFF 54 63 dB Rg = 600Ω; VO = 0dB; CCIR/ARM; Dolby ON 56 72 dB Rg = 600Ω; f = 1KHz Dolby OFF 50 64 dB 70 dB 70 dB 75 dB Rg = 600Ω; f = 1KHz Dolby ON CT Channel Cross Talk % % Rg = 600Ω; f = 1KHz Dolby OFF 56 Rg = 600Ω; f = 1KHz Dolby ON Figure 2: Audio Music Sensor AMS Gin RB IN-L 100K R9 Vs 6 - + Vth0 R7 500K PROGRAM DETECTION TIME - LIMITER AMPLIFIER 23 INTP 0.1µF C7 SIGNAL DETECT. COMPARATOR + + IN-R 8 COMP1 NOR1 AMS th Q1 Vs Vth1 Q Q FF1 S R POWER-ON RESET R Q2 Q FF2 S COMP2 7 9 AMS SW 22 Vth2 21 - AMS OUT + 0.22µF C8 1K Rp20 20 T2 INTS D93AU051A R9 C15 T1 SPACE DETECTION TIME C9 Vs 7/20 TDA7336 AUDIO MUSIC SENSOR (See Figure 2) Aim of this section is to detect interprogram spaces present on a recorded tape. Both the blanks (interprogram spaces) and the programs minimum detectable durations can be easily set by means of 2 external and independent time constants. Also the minimum detectable input signal level can be externally adjusted, by a dedicated gain network. Main blocks are: Variable gain limiter amplifier Signal detector circuitry Logic blocks able to avoid unproperoperations. Operations Description (refer to the simplified schematic of Figure 2). a)The two channels left and right mean signal coming from the preamp chain (AC coupled) are added (current) at the AMS input and presented to the limiter amplifier. The limiter amplifier gain is internally fixed to 40dB, and it could be reduced by the R8 external resistor. The AMSVth threshold is fixed at 1V. The following signal detector comparator informs of the presence of music signal (High level out) and avoids the erroneous detection of very low signal (like noise) as real program. b)The system moves in blank detection mode everytime the supply is turned on or, with power supplied, the AMS On/Off pin (to be driven by an open collector output) is turned off (T1 open). Once this condition has happened, the capacitor C 15 charges, defining a minimum reset time, long enough to reset the Flip-Flops FF1 and FF2 and to descharge the program detector external C7 capacitor. The charging current at the AMS SW pin is about 10µA. It follows that the reset time (C15 x Vpin7)/IC15 is given approximately by 0.122 x C15 ns where C15 is in µF. c)From now on where the sum input signal (leftright) amplified by the limiter exceeds the sig- 8/20 nal detector threshold (3) the capacitor C7 is forced to charge. When the voltage across this capacitor reaches the comparator COMP1 threshold voltage Vth1 (approx. 2 Vbe) FF1 is set and FF2 is reset. (4) It follows that Q1 is turned on discharging the program detection capacitor (C7). d)Always when there is a recorded zone, Q1 is on; it becomes off only if a blank section is reached. When, with a time constant controlled by the R9, C9 network the voltage at space detection time pin reaches Vth2 threshold (comparator COMP2) a true blank section is detected and the FF2 is set. (The minimum charging time is approximately given by: 0.69 x C9 x R9 [sec] In this condition Q2 is on, forcing the open collector AMS output to go low, informing the user that a true blank section has been detected. The state is then able to start from the above point c). Figures 3-4 show the signal behaviour. The device is able to prevent false interspace detection and the end of the tape. (see Fig. 4). Note: (3): minimum RMS input signal is given by: Vin = AMSVth ⋅ 1K + R8 ⋅ 0.6 101K + R8 where Vin is the mean of left and right channels:: Vin = Vright + Vleft 2 (4): the charging current at pin 8 is about 20µA (half input signal) so program detection time constant is given by: C7 x 2Vbe = 70 x C7 [µF] = [msec] 20µA It is recommended to insert a resistor (R7) high enough to prevent fast C7 capacitor discharging. TDA7336 Figure 3: AMS Timing Diagram Figure 4 9/20 TDA7336 ELECTRICAL COMPONENT DESCRIPTION (see figure 1) COMPONENT P R E A M P A M S D O L B Y TR1,TR2 C1, C2 C3, C4 R1, R2 R3, R5 R4, R6 C5, C6 RECOMMENDED VALUE 1KΩ 1µF 10nF 1.2KΩ 6.8KΩ 300KΩ 0.33µF ±10% PURPOSE Left/Right Channel IN/OUT equalizer filter TR fixes the gain 150msec NORMAL 70µsec METAL Preamplifier out to Dolby B input coupling capacitor R8 C8 10KΩ 0.22µF R7 C7 470KΩ 0.1µF Set the interprogram detection time: INTP = 70 x 10-3 x C7[µF] = [sec] R9 C9 100KΩ 1µF Set the interspace detection time: INTS = 0.69 x C9 x R9 sec C15 100nF It fixes music search reset time; Tres = 0.122 x C15[µF] = [sec] if C15 expressed in µF Define the AMS input threshold level Vin ⋅ 101K + R8 ⋅ 1.5 > 1V 1K + R8 where Vin = (Vright + Vleft)/2 C10, C11 0.68µF ±10% Dolby output coupling capacitors C12, C13 Dolby time constants C14 4.7µF ±10% 4.7µF R11 43KΩ It fixes the Iref current C16 R16 0.1µF 30KΩ If fixes the mute time (typ 10msec). Reference voltage external capacitor PINS DESCRIPTION: Internal Configuration Figure 5: PINS: 2 - 27 10/20 Figure 6: PINS: 6 - 23 TDA7336 PINS DESCRIPTION: Internal Configuration Figure 7: PINS: 12 - 17 Figure 8: PIN: 8 Figure 9: PINS: 3 - 26 Figure 10: PINS: 4 - 25 Figure 11: PINS: 5 - 24 Figure 12: PINS: 7 11/20 TDA7336 PINS DESCRIPTION: Internal Configuration Figure 13: PINS: 11 - 18 Figure 14: PIN: 13 Figure 15: PIN: 9 Figure 16: PIN: 21 Figure 17: PIN: 20 Figure 18: PIN: 28 12/20 TDA7336 PINS DESCRIPTION: Internal Configuration Figure 19: PIN: 19 - 10 Figure 20: PIN: 16 DEVICE CHARACTERISTICS Figure 21: Quiescent Current vs. Supply Voltage Figure 22: Quiescent Current vs. Temperature Figure 23: THD vs Supply Voltage Figure 24: THD vs Frequency 13/20 TDA7336 DEVICE CHARACTERISTICS (continued) Figure 25: THD vs. Output Signal Figure 26: THD+N vs. Frequency Figure 27: Channel Separation vs. Frequency Figure 28: Cross Talk vs. Frequency Figure 29: Ripple Rejection vs. Frequency Figure 30: Ripple Rejection vs. Frequency 14/20 TDA7336 DEVICE CHARACTERISTICS (continued) Figure 31: Ripple Rejection vs. Frequency Figure 32: Mute Attenuation vs. Frequency Figure 33: Mute Threshold Figure 34: Vref & Iref vs Supply Voltage Figure 35: Vref & Iref vs Temperature Figure 36: D.C. Voltage pin 13 vs. Supply Voltage 15/20 TDA7336 DEVICE CHARACTERISTICS (continued) Figure38: Noise Reduction Threshold Figure 37: Equalizer Threshold Figure 40: Load Characteristics Figure 39: NAB Network Normal Metal Figure 41: Signaling Handling vs. Supply Voltage 16/20 Figure 42: Signal Handling vs. Temperature TDA7336 DEVICE CHARACTERISTICS (continued) Figure 43: AMS Threshold vs. Frequency Figure 44: AMS Threshold vs. Rex Figure 45: AMS Reset Time vs. Cex Figure 46: AMS Interprogram vs. C7 Figure 47: Interprogram Charging Current Figure 48: Interspace vs. C9 17/20 TDA7336 DEVICE CHARACTERISTICS (continued) Figure 49: Dolby-B Table 18/20 TDA7336 mm DIM. MIN. TYP. A inch MAX. MIN. TYP. 2.65 MAX. 0.104 a1 0.1 0.3 0.004 0.012 b 0.35 0.49 0.014 0.019 b1 0.23 0.32 0.009 0.013 C 0.5 c1 0.020 45° (typ.) D 17.7 18.1 0.697 0.713 E 10 10.65 0.394 0.419 e 1.27 0.050 e3 16.51 0.65 F 7.4 7.6 0.291 0.299 L 0.4 1.27 0.016 0.050 S OUTLINE AND MECHANICAL DATA SO28 8 ° (max.) 19/20 TDA7336 Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. The ST logo is a registered trademark of STMicroelectronics 1999 STMicroelectronics – Printed in Italy – All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com 20/20