UTC2003 LINEAR INTEGRATED CIRCUIT YOUWANG ELECTRONICS CO.LTD 1 10W CAR RADIO AUDIO AMPLIFIER

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1 UTC W CAR RADIO AUDIO AMPLIFIER DESCRIPTION The UTC has improved performance with the same pin configuration as the UTC.The additional features of UTC,very low number of external components, ease of assembly, space and cost saving, are maintained. The device provides a high output current capacity(up to.a) very low harmonic and crossover distortion.completely safe operation is guaranteed due to protection against DC and AC short circuit between all pins and ground, thermal over-range, load dump voltage surge up to V and fortuitous open ground. TO-B ABSOLUTE MAXIMUM RATINGS(Ta= C) CHARACTERISTICS SYMBOL VALUE UNITS Peak Supply Voltage Vs V DC supply Voltage Vs 8 V Operating supply voltage Vs 8 V Output peak current(repetitive) Io. A Output peak current( non repetitive) Io. A Power dissipation at Tcase=9 C W Storage temperature Tstg -~+ C junction temperature Tj -~+ C PIN CONNECTION Non inverting input Inverting input Ground Output Supply Voltage YOUWANG ELECTRONICS CO.LTD

2 UTC SCHEMATIC DIAGRAM TEST CIRCUIT +Vs C nf μf Vi C μf UTC C μf Rx 9 Cx 9nF C 7μF R R. R nf RL Rx=*R Cx=/( B*R) YOUWANG ELECTRONICS CO.LTD

3 UTC +Vs ma nf F +Vs C nf Vi nf UTC F Vi C F UTC C F 7 F V R R. RL Rx 9 Cx 9nF C 7 F R R RL R. nf DC Test Circuit Rx=*R Cx=/(pB*R) AC Test Circuit ELECTRICAL CHARACTERISTICS(Refer to the test circuit, Vs=V,Ta= C) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT DC CHARACTERISTICS Supply Voltage Vs 8 8 V Quiescent Output Vo V Voltage Quiescent drain current Id ma AC CHARACTERISTICS d=%, RL=Ω 6 Output power Po RL=Ω W RL=.Ω 7. RL=.6Ω Po=.W,RL=Ω mv Input sensitivity Vi Po=6W,RL=Ω mv Po=.W,RL=Ω mv Po=W,RL=Ω mv Input saturation Vi(rms) mv voltage Frequency B Po=W,RL=Ω Hz response(-db) Distortion D Po=. to.w,rl=ω. % Po=. to 7.W,RL=Ω. (continued) YOUWANG ELECTRONICS CO.LTD

4 UTC PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT Input Ri open loop, 7 kω Resistance(pin ) Input noise current e N 6 pa Input noise voltage I N μv open loop Gvo 8 db voltage gain 6 db closed loop Gvc,RL=Ω voltage gain 9.. db Efficiency η Po=6W,RL=Ω 69 % Po=W,RL= 6 % Supply voltage rejection SVR f=hz,vripple=.v Rg=k RL= 6 db Vo(V) Fig. Quiescent output voltage vs.supply voltage Id(mA) Fig. Quiescent drain current vs.supply voltage Po Fig. Output power vs.supply voltage 8 8 Gv=dB d=% R= R= R=. R= 8 6 Vs(V) 8 6 Vs(V) Vs(V) Fig. output power vs.load resistance Fig. Gain vs. Input sensitivity Fig.6 Gain vs. Input sensitivity Po 6 Vs=6V Gv=dB d=% 8 8 Gv=dB RL= 8 8 Gv=dB RL= Vs=.V 8 Vs=V 6 6 Vs=8V RL( ) Vi(rms) Vi(rms) Fig.7 Distortion vs. output power Fig.8 Distortion vs. frequency Fig.9 Supply voltage rejection vs. voltage gain d(%) Gv=dB Vs=.V R= R=. R= R=.6 d(%).8.6 Gv=dB Vs=.V RL= / SVR (db) - - fripple=hz Vs=,V RL=. Rg=k. Po=.W -.. Po=mW -.. Po Frequency (Hz) - Gv(dB) YOUWANG ELECTRONICS CO.LTD

5 UTC SVR (db) - Fig. Supply voltage rejection vs.frequency Vs=.V Vripple=.V Gv=dB Rg=k R= 8 6 Fig. Power dissipation and efficiency vs. output power(rl= ) Vs=.V Gv=dB (%) Fig. Power dissipation and efficiency vs. output power(rl= ) Vs=.V Gv=dB (%) R= -8 frequency(hz) 6 8 Po 6 8 Po Fig. Maximum Power dissipation and supply voltage(sine wave operation) Fig. Maximum allowable dissipation and ambient temperature infinite heatsink Cx (nf) Fig. Typical values of capacitor(cx) for different values of frequency response B=kHz B=kHz RL=.6 B=kHz RL= RL=. RL= /W /W R=. Vs(V) Tamb( ) 6 8 Gv(dB) APPLICATION INFORMATION +Vs Vi C μf μf UTC C nf C μf Rx 9 Cx 9nF C 7μF R R R. nf RL Rx=*R Cx=/( B*R) Fig 6 Typical application circuit YOUWANG ELECTRONICS CO.LTD

6 UTC Vs=.V.μF.μF.μF UTC.μF RL= UTC C μf 6 C μf 6 Fig.8 W Bridge configuration application The Values of the capacitors C and C are different to optimize the SVR(Typ. db) Vs=.V.μF UTC.μF.μF RL=.μF UTC.μF C μf 6 nf Fig. Low cost bridge configuration application circuit(po=8w) BUILT-IN PROTECTION SYSTEMS Load dump voltage surge The UTC has a circuit which enables it to withstand a voltage pulse train, on pin, of the type shown in Fig.. If the supply voltage peaks to more than V, then an LC filter must be inserted between the supply and pin, in order to assure that the pulses at pin will be head within the limits shown in Fig.. A suggested LC network is shown in Fig..With this network, a train of pulses with amplitude up to V and width of ms can be applied at point A. This type of protection is ON when the supply voltage(pulsed or DC) exceeds 8V.For this reason the maximum operating supply voltage is 8V. YOUWANG ELECTRONICS CO.LTD 6

7 UTC Vs (V) t=ms A mh B. From Supply Voltage μf 6V To Pin t=ms t Short Circuit (AC and DC Conditions) The UTC can withstand a permanent short-circuit on the output for a supply voltage up to 6V. Polarity inversion High current(up to A) can be handled by the device with no damage for a longer period than the blow-out time of a quick A fuse(normally connected in series with the supply). The feature is added to avoid destruction if, during fitting to the car, a mistake on connection of the supply is made. Open ground When the radio is in the ON condition and the ground is accidentally opened, a standard audio amplifier will be damaged. On the UTC protection diodes are included to avoid any damage. Inductive load A protection diode is provide between pin and pin (see the internal schematic diagram) to allow use of the UTC with inductive loads. In particular,theutc can drive a coupling transformer for audio modulation. DC voltage The maximum operating DC voltage on the UTC is 8V. However the device can withstand a DC voltage up to 8V with no damage. This could occur during winter if two batteries were series connected to crank the engine. Thermal shut-down The presence of a thermal limiting circuit offers the following advantages: ).an overload on the output (even if it is permanent),or an excessive ambient temperature can be easily withstood. ).the heat-sink can have a smaller factor compared with that of a conventional circuit. There is no device damage in case of excessive junction temperature: all that happens is that Po( and there ) and Id are reduced. YOUWANG ELECTRONICS CO.LTD 7

8 UTC APPLICATION SUGGESTION The recommended values of the components are those shown on application circuit of Fig.6. Different values can be used. The following table can help the designer. Component Recommended value Purpose Large than recommended value Large than recommended value R (Gv-)*R gain setting. increase of Gain R.Ω gain and SVR Decrease of SVR setting. R Ω Frequency stacility Danger of oscillation at high frequencies with inductive loads. Rx *R Upper frequency Poor high frequencies Dange of oscillation cutoff attenuation C.μF Input DC decoupling Noise at switch-on switch-off C 7μF Ripple rejection Decrease of SVR C.μF Supply voltage bypass Dange of oscillation C μf Output coupling to load Higher low frequency cutoff C.μF Frequency stability Danger of oscillation at high frequencies with inductive loads. Cx /(π*b*r) Upper frequency cutoff smaller bandwidth Larger bandwidth YOUWANG ELECTRONICS CO.LTD 8