STA5100 140W MONO ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ POWER AMPLIFIER MONOCHIP BRIDGE MONO AMPLIFIER FOR BASH ® ARCHITECTURE 110W OUTPUT POWER @ R L = 4 Ω, THD = 0.5% 140W OUTPUT POWER @ R L = 4 Ω, THD = 10% HIGH DYNAMIC PREAMPLIFIER INPUT STAGES EXTERNAL PROGRAMMABLE FEEDBACK TYPE COMPRESSORS AC COUPLED INPUT TO CLASS AB BRIDGE OUTPUT AMPLIFIER PRECISION RECTIFIERS TO DRIVE THE DIGITAL CONVERTER ON-OFF SEQUENCE/ TIMER WITH MUTE AND STANDBY PROPORTIONAL OVER POWER OUTPUT CURRENT TO LIMIT THE DIGITAL CONVERTER ABSOLUTE POWER BRIDGE OUTPUT FLEXIWATT27 ■ ■ ■ ■ ■ TRANSISTOR POWER PROTECTION ABSOLUTE OUTPUT CURRENT LIMIT INTEGRATED THERMAL PROTECTION POWER SUPPLY OVER VOLTAGE PROTECTION FLEXIWATT POWER PACKAGE WITH 27 PIN BASH® licence required DESCRIPTION The STA5100 is a fully integrated power module designed to implement a BASH® amplifier when used in conjunction with STABP01 digital processor. BLOCK DIAGRAM +VS GND -VS OUT_ PRE TRK PWR_INP ABSOLUTE VALUE BLOCK + - CD+P +2 ∆G IN_PRE OUTP +2 OUTP COMPRESSOR OUTPUT BRIDGE CD-P V/l ATT_REL CD+ PEAK DETECTOR S1 Ict OVER VOLTAGE PROTECTION SOA DETECTOR PROT. TURNON/OFF SEQUENCE STBY/MUTE THRESH TRK_OUT THERMAL PROTECTION CD+N -1 OUTN -1 OUTN OUTPUT BRIDGE CD-N D01AU1280 July 2003 1/14 STA5100 DESCRIPTION (continued) Notice that normally only one Digital Converter is needed to supply a stereo or multi-channel amplifier system, therefore most of the functions implemented in the circuit have summing outputs The signal circuits are biased by fixed negative and positive voltages referred to Ground. Instead the final stages of the output amplifiers are supplied by two external voltages that are following the audio signal . In this way the headroom for the output transistors is kept at minimum level to obtain a high efficiency power amplifier. The Compressor circuits, one for each channel, performs a particular transfer behavior to avoid the dynamic restriction that an adaptive system like this requires. To have a high flexibility the attack / release time and the threshold levels are externally programmable. The tracking signal for the external digital converter is generated from the Absolute Value block that rectifies the audio signal present at the compressor output. The outputs of these blocks are decoupled by a diode to permit an easy sum of this signal for the multichannel application. The output power bridges have a dedicated input pin to perform an AC decoupling to cancel the compressor output DC offset. The gain of the stage is equal to 4 (+12dB). A sophisticated circuit performs the output transistor power detector that , with the digital converter, reduces the power supply voltage . Moreover, a maximum current output limiting and the over temperature sensor have been added to protect the circuit itself. The external voltage applied to the STBY/MUTE pin forces the two amplifiers in the proper condition to guarantee a silent turnon and turn-off. ABSOLUTE MAXIMUM RATINGS Symbol Parameter Value Unit +Vs Positive supply voltage referred to pin 13 (GND) 30 V -Vs Negative supply voltage referred to pin 13 (GND) -24 V VCD+ Positive supply voltage tracking rail referred to pin 13 (GND) 22 V VCD+ Positive supply voltage operated to Vs+(1) 0.3 V VCD- Negative supply voltage referred to -Vs (1) -0.3 V VCD- Negative supply voltage tracking rail referred to pin 13 (GND) -22 V VAtt_Rel Pin 3 Negative & Positive maximum voltage reffered to GND (pin 13) -0.5 to +20 V VPwr_Imp VTrk Pin 7, 10 Negative & Positive maximum voltage referred to GNC (pin 13) -20 to +20 V VIn_pre Pin 8 Negative & Positive maximum voltage referred to GND (pin 13) -0.5 to +0.5 V Vthreshold Pin 17 Negative & Positive maximum voltage referred to GND (pin 13) -7 to +0.5 V Istb-max Pin 11 maximum input current (Internal voltage clamp at 5V) 500 µA Pin 11 negative maximum voltage referred to GND (pin 13) -0.5 V Value Unit 150 °C 1 °C/W Vstbymute Notes: 1. VCD- must not be more negative than -Vs and VCD+ must not be more positive than +VS THERMAL DATA Symbol Tj Parameter Max Junction temperature Rth j_case Thermal Resistance Junction to case .............................. ..max 2/14 STA5100 OPERATING RANGE Symbol Parameter Value Unit +Vs Positive supply voltage +20 to +30 V -Vs Negative supply voltage -10 to -22 V 5V ≤ (Vs+ - VCD+) ≤ 10V V ∆Vs+ Delta positive supply voltage VCD+ Positive supply voltage tracking rail +3 to +17 V VCD- Negative supply voltage tracking rail -3 to -17 V Current at pin In_Pre related to compressor behaviour -1 to +1 mA peak Voltage at pin Threshold -5 to 0 V Ambient Temperature Range 0 to 70 °C 200 µA Iin_Max Vtrheshold Tamb Isb_max Pin 11 maximum input current (Internal voltage clmp at 5V) PIN CONNECTION N.C. CD-N OUTN OUTN N.C. CD+N N.C. N.C. N.C. THRESHOLD CD+ TRK_OUT +VS GND PROTECTION TRK STBY/MUTE IN_PRE OUT_PRE PWR_INP CD+P OUTP OUTP ATT-REL -VS CD-P -Vs 27 1 D01AU1281 3/14 STA5100 PIN FUNCTION N° Name 1 -Vs 2 CD-P 3 Att_Rel 4 OutP Channel P 5 OutP Channel P 6 CD+P Channel P positive power supply 7 Pwr_Inp 8 In_pre 9 Out_pre 10 Trk 11 Stby/mute Standby/mute input voltage control 12 Protection Protection signal for STABP01 digital processor 13 Gnd Analog Ground 14 +Vs Positive Bias Supply 15 CD+ Time varying tracking rail positive power supply 16 Trk_out Reference output for STABP01 digital processor 17 Threshold 18 N.C. 19 N.C. 20 N.C. 21 N.C. 22 CD+N Channel N positive power supply 23 OutN Channel N 24 OutN Channel N 25 N.C. 26 CD-N 27 -Vs 4/14 Description Negative Bias Supply Channel P Time varying tracking rail negative power supply Attack release rate Input to power stage Pre-amp input (virtual ground) Output channel Absolute value block input Compressor threshold input Channel N Time varying tracking rail negative power supply Negative Bias Supply STA5100 ELECTRICAL CHARACTERISTCS (Test Condition: Vs+ = 26V, Vs- = -22V, VCD+ = 17V, VCD- = -17V, RL = 4Ω, external components at the nominal value f = 1KHz, Tamb = 25°C unless otherwise specified Symbol Parameter Test Condition Min. Typ. Max. Unit 10 11 12 Vpeak 0.8 mA 0.65 12 V V V -1 V PREAMPLIFIER AND COMPRESSOR Vout clamp Maximum Voltage at Out_pre pin Iin Audio input current Vcontrol Voltage at Attack_Release pin Attenuation = 0dB Attenuation = 6dB Attenuation = 26dB 0.35 6 0 0.5 9 Th Input voltage range for the compression Zth Input impedance of Threshold pin Voffset Output Offset at Out_pre pin with: VCRT= 0V; Attenuation = 0dB VCRT= 0.5V; Attenuation = 6dB VCRT= 9V; Attenuation = 26dB Distortion at Out_pre: VCRT= 0V; Attenuation = 0dB VCRT= 0.5V; Attenuation = 6dB VCRT= 9V; Attenuation = 26dB 0.01 VCRT= 0V; Attenuation = 0dB VCRT= 0.5V; Attenuation = 6dB VCRT= 9V; Attenuation = 26dB 10(2) 50 60 µV µV µV 1.5 mA VComp_ THD EN Noise at Out_pre pin : Ict Attack time current at pin Attack_release -5 100 KΩ -10 -250 -450 10 250 450 mV mV mV 5 5 % % % 2. This value is due to the thermal noise of the external resistors Rr and Ri. TRACKING PARAMETERS Tracking reference voltage gain 13 14 Vtrk_out Tracking ref. output voltage 0 20 Itrk_out Current capability 5 6 Ztrk_in Input impedance (Trk) Gtrk 15 V V 7 1 mA MΩ OUTPUT BRIDGE Gout Half Output bridge gain 5.5 6 6.5 dB Gch Output bridge differential gain 11 12 13 dB ∆Gch Output bridges gain mismatch -1 1 dB Pout Continuous Output Power THD = 0.5% THD = 10% THD Total harmonic distortion of the output bridge Po = 5W 100 125 110 140 W W 0.01 % f = 20Hz to 20KHz; Po = 50W VOff Output bridge D.C. offset EN Noise at Output bridge pins Zbr_in Input impedance f = 20Hz to 20KHz; Rg = 50Ω 0.1 % 50 mV µV 12 100 140 180 KΩ 5/14 STA5100 ELECTRICAL CHARACTERISTCS (continued) Symbol Parameter Test Condition Min. IO = 1A Typ. Max. Unit 100 200 mΩ Rdson Output power Rdson OLG Open Loop Voltage Gain 100 dB GB Unity Gain Bandwidth 1.4 MHz SR Slew Rate 7 V/µs PROTECTION Vstby Stby voltage range 0 0.8 V Vmute Mute voltage range 1.6 3 V Vplay Play voltage range 4 5 V Th1 First Over temperature threshold 130 °C Th2 Second Over temperature threshold 150 °C Unbal. Ground Upper Unbalancing ground threshold Referred to (CD+ - CD-)/2 5 V Unbal. Ground Lower Unbalancing ground threshold Referred to (CD+ - CD-)/2 -5 V Under voltage threshold |Vs+| + |Vs-| 20 V Pd_reg. Power dissipation threshold for system regulation Iprot = 50µA; @ Vds = 10V Pd_max Switch off power dissipation threshold @ Vds = 10V 96 W Iprot Protection current slope for Pd > Pdreg 400 µA/W Ilct Limiting Current threshold UVth 50 11 62 12 13 W A I+Vs Positive supply current Stby (Vstby/mute pin = 0V) Mute (Vstby/mute pin = 2.5V) Play (Vstby/mute pin = 5V no signal) 4 30 30 mA mA mA I-Vs Negative supply current Stby (Vstby/mute pin = 0V) Mute (Vstby/mute pin = 2.5V) Play (Vstby/mute pin = 5V no signal) 4 30 30 mA mA mA ICD+ Positive traking rail supply current Stby (Vstby/mute pin = 0V) Mute (Vstby/mute pin = 2.5V) Play (Vstby/mute pin = 5V no signal) 100 110 110 µA mA mA ICD- Negative traking rail supply current Stby (Vstby/mute pin = 0V) Mute (Vstby/mute pin = 2.5V) Play (Vstby/mute pin = 5V no signal) 100 110 110 µA mA mA 6/14 STA5100 FUNCTIONAL DESCRIPTION The circuit contains all the blocks to build a mono amplifier. It is based on the Output Bridge Power Amplifier, and its protection circuit. Moreover, the compression function and a signal rectifier are added to complete the circuit. The operation modes are driven by The Turn-on/off sequence block. In fact the IC can be set in three states by the Stby/mute pin: Standby ( Vpin < 0.8V), Mute (1.6V < Vpin < 3V), and Play (Vpin > 4V). In the Standby mode all the circuits involved in the signal path are in off condition, instead in Mute mode the circuits are biased but the Speakers Outputs are forced to ground potential. These voltages can be get by the external RC network connected to Stby/Mute pin. The same block is used to force quickly the I.C. In standby mode or in mute mode when the I.C. dangerous condition has been detected. The RC network in these cases is used to delay the Normal operation restore. The protection of the I.C. are implemented by the Over Temperature, Unbalance Ground, Output Short circuit, Under voltage, and output transistor Power sensing as shown in the following table: Table 1. Protection Implementation Fault Type Condition Protection strategy Action time Release time Chip Over temperature Tj > 130 °C Mute Fast Slow Related to Turn_on sequence Chip Over temperature Tj > 150 °C Standby Fast Slow, Related to Turn_on sequence Unbalancing Ground |Vgnd| > ((CD+) (CD-))/2 + 5V Standby Fast Slow, Related to Turn_on sequence Short circuit Iout > 12A Standby Fast Slow, related to Turn_on sequence Under Voltage |Vs+| + |Vs-|< 20V Standby Fast Slow, related to Turn_on sequence Extra power dissipation at output transistor Pd tr. > 50W Reducing DIGITAL CONVERTER output voltage. Related to the DIGITAL CONVERTER Related to the DIGITAL CONVERTER Maximum power dissipation at output transistor Pd tr. > 96W Standby Fast Slow, related to Turn_on sequence See the POWER PROTECTION paragraph for the details Compression An other important function implemented, to avoid high power dissipation and clipping distortion, is the Compression of the signal input. In fact the preamplifier stage performs a voltage gain equal to 5, fixed by Ri and Rr external resistor, but in case of high input signal or low power supply voltage, its gain could be reduced of 26dB. This function is obtained with a feedback type compressor that , in practice, reduces the impedance of the external feedback network. The behavior of compression it's internally fixed but depends from the Audio input voltage signal level, and from the Threshold voltage applied to the Threshold pin. The attack and release time are programmable by the external RC network connected to the Att_Rel pins. The constraints of the circuit in the typical application are the following: Vthreshold range = -5 to 0 Vin peak max = 8V Vout peak max = 10V 7/14 STA5100 Gain without compression (G) =5 Max Attenuation ratio = 26 dB The following graph gives the representation of the Compressor activation status related to the Vthreshold and the input voltage. The delimitation line between the two fields, compression or not, is expressed by the formula : 2 ⋅ Vthresh old V in = ------------------------------------------G Where G is the preamplifier gain without compression. In the compression region the gain of the preamplifier will be reduced (G = 2·Vthreshold/Vin) to maintain at steady state the output voltage equal 2*|Vthreshold| . Instead in the other region the compressor will be off (G = 5). The delimitation line between the two fields can be related to the output voltage of the preamplifier: in this case the formula is : V o ut = 2 ⋅ Vthre sho ld Figure 1. Compressor activation field VIN PEAK 8 6 COMPRESSION G<5 4 2 G=5 D01AU1264 1 2 3 4 5 |Vthreshold| The relative attenuation introduced by the variable gain cell is the following : V th 2 Attenu atio n = 20 log --- ⋅ ---------------------5 V in _peak The total gain of the stage will be: Gdb = 20log5 + Attenuation The maximum input swing is related to the value of input resistor, to guarantee that the input current remain under Iin_Max value (1 mA). V in_peak R i > ---------------------I in_max 8/14 STA5100 Figure 2. Compressor attenuation vs. input amplitude Attenuation(dB) 0 -6 |Vth -12 =5| |Vth -18 |Vt =2. 5| h= 1| -24 D01AU1265 1 2 3 4 5 6 7 8 |Vinpk| ABSOLUTE VALUE BLOCK The absolute value block rectifies the signal after the compression to extract the control voltage for the external digital converter. The output voltage swing is internally limited, the gain is internally fixed to 14. The input impedance of the rectifier is very high , to allow the appropriate filtering of the audio signal before the rectification (between Out_pre and Trk pins). OUTPUT BRIDGE The Output bridge amplifier makes the single-ended to Differential conversion of the Audio signal using two power amplifiers, one in non-inverting configuration with gain equal to 2 and the other in inverting configuration with unity gain. To guarantee the high input impedance at the input pins, Pwr_Inp1 and Pwr_Inp2, the second amplifier stages are driven by the output of the first stages respectively. POWER PROTECTION To protect the output transistors of the power bridge a power detector is implemented (fig 3). The current flowing in the power bridge and trough the series resistor Rsense is measured reading the voltage drop between CD+1 and CD+. In the same time the voltage drop on the relevant power (Vds) is internally measured. These two voltages are converted in current and multiplied: the resulting current , Ipd, is proportional to the instantaneous dissipated power on the relevant output transistor. The current Ipd is compared with the reference current Ipda, if bigger (dissipated power > 50W) a current, Iprot, is supplied to the Protection pin. The aim of the current Iprot is to reduce the reference voltage for the digital converter supplying the power stage of the chip, and than to reduce the dissipated power. The response time of the system must be less than 200µSec to have an effective protection. As further protection, when Ipd reaches an higher threshold (when the dissipated value is higher then 96W) the chip is shut down, forcing low the Stby/Mute pin, and the turn on sequence is restarted. 9/14 STA5100 Figure 3. Power Protection Block Diagram RSENSE CD+ CD+P ILOAD V/I OC1 ILIM MULTIPLIER CURRENT COMP X PDP1 IPD V/I IPDP I_PD TO TURN-ON/OFF SEQUENCE CURRENT COMP IPD OPA TO TURN-ON/OFF SEQUENCE IPROT TO PROT PAD OPA IPDA OUTP CD- D01AU1282 OUTP In fig. 4 there is the power protection strategy pictures. Under the curve of the 50W power, the chip is in normal operation, over 96W the chip is forced in Standby. This last status would be reached if the digital converter does not respond quikly enough reducing the stress to less than 96W. The fig.5 gives the protection current, Iprot, behavior. The current sourced by the pin Prot follows the formula: –4 ( Pd – Pd_av _th ) ⋅ 5 ⋅ 10 Iprot ≡ -----------------------------------------------------------------1.25V for Pd < Pd_av_th the Iprot = 0 Independently of the output voltage, the chip is also shut down in the folowing conditions: When the currentthrough the sensing resistor, R sense, reaches 12A (Voltage drop (CD+) - (CD+1) = 700mV). When the average junction temperature of the chip reaches 150°C. When the ground potential differ from more than 5V from the half of the power supply voltage, ((CD+)-(CD-))/2 When the sum of the supply voltage |Vs+| + |Vs-| <20V The output bridge is muted when the average junction temperature reaches 130°C. 10/14 STA5100 Figure 4. Power protection threshold Figure 5. Protection current behaviour Ids(mA) Iprot(mA) Ilim=12A 12 20 10 Standby k Buc 8 Pd_Max=96W Lim 6 it a 10 on ti 4 2 Iprot slope=0.4mA/W Pd_reg=50W Normal Operation 0 10 20 30 34 40 50 Vds(V) D01AU1303 20 D01AU1304 40 60 80 100 120 Pd(W) Figure 6. Test and Application Circuit C3 C12 C4 R2 INPUT1 OUT_PRE R1 8 R4 R6 R5 C1 TRK 9 PWR_INP 10 7 4 OUTP OUTP IN_PRE R3 ATT_REL 5V 3 5 R10 CD+P CD+ CD+ R11 R16 C8 CD+N +VS +VS C10 R15 C11 -VS -VS CD- CD-N CD-P TRK-OUT TRK-OUT PROT R13 15 THRESH R12 11 22 STBY/ MUTE R14 C9 14 PROT THRESH MUTE STBY R15 STA5100 13 24 OUTN C7 -VS D1 R14 6 C6 GND C9 R13 OUTP C2 27 1 OUTN 23 OUTN 2 26 16 12 17 D01AU1305 11/14 STA5100 EXTERNAL COMPONENTS Name Function Value Formula Ri R1 Input resistor 10KΩ (|G| = 5, Rr = 50KΩ) Rr R i = ------G Rr R2 Feedback resistor 50KΩ (|G| = 5, Ri = 10KΩ Rr = G ⋅ Rr Cac C1 AC Decoupling capacitor 100nF (fp = 16Hz, Rac =100KΩ ) 1 Cac = --------------------------------2π ⋅ fp ⋅ Rac Cct C2 Capacitor for the attack time 2.2µF (Tattack = 13mSec, Vcontrol = 9V, Ict = 1.5mA) Ict Cct = attack ------------------------Vcontrol R3 Release constant time Resistor 470KΩ (t = 1 Sec. , Cct = 2.2 µF ) τ Rct = --------Cct R4 Resistor for tracking input voltage filter 10KΩ R5 Resistor for tracking input voltage filter 56KΩ R6 Resistor for tracking input voltage filter 10KΩ C3 Capacitor for Tracking input voltage filter 1nF C4 Dc decoupling capacitor 1µF R7 Bias Resistor for Stby/Mute function 10KΩ R8 Stby/Mute constant time resistor 30KΩ R9 Mute resistor 30KΩ C5 Capacitor for Stby/Mute resistor 2.2µF R10 = R11 Sensing resistor for SOA detector 60mΩ 5% 4W R12 Conversion resistor for threshold voltage 100KΩ Power supply filter capacitor 100nF C6 = C7 R15 = R16 C8 = C9 Centering resistor Tracking rail power supply filter 680nF R13 Protection 1KΩ R14 TRK_out 40KΩ C10 = C11 Power supply filter capacitor 470 µF , 63V C12 Feedback capacitor 100pF D1 Schottky diode SB360 Note: Vcontrol is the voltage at Att_Rel pin. 12/14 400 Ω , 1W STA5100 DIM. MIN. 4.45 1.80 A B C D E F (1) G G1 H (2) H1 H2 H3 L (2) L1 L2 (2) L3 L4 L5 M M1 N O R R1 R2 R3 R4 V V1 V2 V3 0.75 0.37 0.80 25.75 28.90 22.07 18.57 15.50 7.70 3.70 3.60 mm TYP. 4.50 1.90 1.40 0.90 0.39 1.00 26.00 29.23 17.00 12.80 0.80 22.47 18.97 15.70 7.85 5 3.5 4.00 4.00 2.20 2 1.70 0.5 0.3 1.25 0.50 MAX. 4.65 2.00 MIN. 0.175 0.070 1.05 0.42 0.57 1.20 26.25 29.30 0.029 0.014 22.87 19.37 15.90 7.95 0.869 0.731 0.610 0.303 4.30 4.40 0.145 0.142 0.031 1.014 1.139 inch TYP. 0.177 0.074 0.055 0.035 0.015 0.040 1.023 1.150 0.669 0.503 0.031 0.884 0.747 0.618 0.309 0.197 0.138 0.157 0.157 0.086 0.079 0.067 0.02 0.12 0.049 0.019 MAX. 0.183 0.079 OUTLINE AND MECHANICAL DATA 0.041 0.016 0.022 0.047 1.033 1.153 0.904 0.762 0.626 0.313 0.169 0.173 5˚ (Typ.) 3˚ (Typ.) 20˚ (Typ.) 45˚ (Typ.) Flexiwatt27 (vertical) (1): dam-bar protusion not included (2): molding protusion included V C B V H H1 V3 A H2 O H3 R3 L4 R4 V1 R2 L2 N L3 R L L1 V1 V2 R2 D R1 L5 Pin 1 R1 R1 E G G1 F FLEX27ME M M1 7139011 13/14 STA5100 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. Specifications 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. 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