Ecler-APA600-pwr-sm维修电路原理图.pdf
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1、 APA1400 APA1000 APA600 SERVICE MANUAL 102345678910102345678910SPCLIPTHPROTSPTHRLEECAPA1400POWERCHANNEL 2CHANNEL 1OFFONSWITCHING POWER MOSFET AMPLIFIERCLIPPROT102345678910102345678910SPCLIPTHPROTSPTHRLEECAPA1000POWERCHANNEL 2CHANNEL 1OFFONSWITCHING POWER MOSFET AMPLIFIERCLIPPROT102345678910102345678
2、910SPCLIPPROTSPTHRLEECAPA600POWERCHANNEL 2CHANNEL 1OFFONSWITCHING POWER MOSFET AMPLIFIERCLIPPROTRadioFans.CN 收音机爱 好者资料库SERVICE MANUAL APA1400/1000/600 INDEX - BLOCK DIAGRAM - FUNCTIONING DESCRIPTION - SCHEMATICS - COMPONENTS LOCATION SCHEMA AND PART LIST - TESTING AND QUALITY CONTROL - TECHNICAL CHA
3、RACTERISTICS - WIRING DIAGRAM - CONFIGURATION DIAGRAM - MECHANICAL DIAGRAM - PACKING DIAGRAM RadioFans.CN 收音机爱 好者资料库author:Queraltdate:000519approved:num:52.0007version:01.00FUNCTIONING DESCRIPTIONtitle:POWER MODULEThe amplifying stage basic structure is actually the one commonly used until now, thi
4、sis, a push-pull mounted A-B class amplifier, using P-type (IRFP9240) and N-type(IRFP240) mosfets.The systems controlling core is a NE5534 OpAmp, which is internally compensated inorder to obtain an amplifying gain ratio equal or greater than 3. The amplifiersfeedback runs through a resistor and a c
5、apacitor associated to the OpAmps non-inverting input.Transistors BF871 and BF872 are common-base configured, becoming actually acurrent source structure. They accomplish a dual function: on one hand, they polarisethe mosfets gate-source junction, keeping them on their conduction knee. On the otherh
6、and, they carry out the OpAmps output voltage variations, referred to signal ground.The polarisation current adjustment is fixed by a 2k5 trimming potentiometer connectedto the BF transistors base. This current is added to the current sources output, whichpasses through the BF-transistors load resis
7、tors. The bias current stability againsttemperature is fixed through the BD437 transistors. Their temperature- dependent baseemitter voltage curve is used to alter adequately the current sources reference voltage.As a consequence, if the temperature rises, the reference voltage decreases, thus thega
8、te-source voltage also does, and finally the bias current also decreases.The Zobel network, formed by a resistor-inductor-capacitor group, and which is locatedat the amplifiers output, intends to keep the amplifiers load impedance as constant aspossible, no matter which load is connected to the stag
9、es output, or which signalfrequency is to be amplified, in order to prevent an inverted-phase feedback signal.In order to avoid a DC offset on the output signal, a diac-triac tandem system is used,which shorts the output to signal ground when the DC level is enough to get the diactriggered. To preve
10、nt this from happening while carrying audio signal (sine-wave,music), the diacs reference voltage is taken from a filter formed by resistor R149 andcapacitor C124.The protection circuitry supervises at any time the power consumed by the MOSFETS.The circuitry basically consists on two sections: MOSFE
11、Ts drain current (Id) monitoringand drain-source voltage (Vds) monitoring.When the drain current exceeds a certain limiting value, a transistor (called control-transistor) becomes conducting, together with an auxiliary circuitry (helper), formed bya transistor (which is the same type as the control-
12、transistor) and a 82V Zener diode.This value determines the point where the auxillary circuitry starts to run. The helper-transistors base-emitter junction curve is used to obtain a non-linear variation on theMOSFETS gate-source voltage control, and thus on their drain current. ECLERSheet 1 of 2auth
13、or:Queraltdate:000519approved:num:52.0007version:01.00FUNCTIONING DESCRIPTIONtitle:POWER MODULEECLERMoreover, as the helper-transistors base-emitter current is temperature-dependent, thecontrolling circuitry (basically the control-transistor) compensates the safe operationarea (SOA) drift due to tem
14、perature.If the MOSFETs drain-source voltage (Vds) drops too low, a second circuitry actuatesto alter thecontrol-transistors triggering level, obtaining a SOA-like curve section anda current stage, which can be adjusted adequately in order to maintain the MOSFETspower consumption as close as possibl
15、e to its SOA.Moreover, the amplifier also includes an ANTICLIP system.When the amplifier reaches its clipping level, the OpAmp becomes unable to keep thesystem under control, and as a consequence V peaks appear at its output (15Vpower supply). This peaks are used to be rectified and sent to an optoc
16、upler (led-resistor) which modifies its impedance as a function of those peaks amplitude. Theresulting impedance is part of a voltage divider, together with the amplifiers inputimpedance. So, as the optocoupler increases its impedance, the amplifiers input signallevel decreases until the system beco
17、mes stable.Also a dual-function temperature control circuitry is provided:- Temperature-depending control of the cooling fan speed, whose voltage supply isvariable between 7 and 14 Vac.- Amplifier shutdown when temperature exceeds approximately 90C.The circuitry is formed byLM35D-type IC, which acts
18、 like a thermal probe, anamplifier, thermal probe level comparator and a 7805-type voltage regulator.The amplifier is responsible for the cooling fan speed control. The comparator triggers arelay, which cuts off the MOSFETs bias current by shunting a 22W resistance to theBF-type transistors load res
19、istors. This way, the output signal of the amplifier iseffectively cutted off.The STAND-BY circuit.This circuit keeps the safety relay closed for about 10 seconds, thus the MOSFETsbias current is cutted off during this period, until the whole system reaches again avoltage-stable situation. Due to th
20、is, hearing annoying transients and noises during startup through the loudspeakers is avoided. This delay is obtained by a RC-cell, whereR=287K, and C=47F/50V. During start up, this RC-cells voltage smoothly rises untilthe 40106-type Trigger-Schmitt trigging level is reached, and the amplifier start
21、sfunctioning. C=47F resets or discharges when the unit is turned off. During a shortperiod of time, a BC817-type transistor acts like a switch, connecting two 75W parallelresistors to C=47/50V.Sheet 2 of 2author:Queraltdate:020430approved:num:40.0048version:01.01C101100nFCXCN41000C102100nFCXCN41000C
22、103100nFCXCN41000C104100nFCXCN41000C10547u/16FCCE100000C10647u/16FCCE100000C10747u/16FCCE100000C10847u/16FCCE100000C109100pFCXCN21000C110100pFCXCN21000C111100pFCXCN21000C112100pFCXCN21000C11322p 2%FCXCN12201C11422p 2%FCXCN12201C11522p 2%FCXCN12201C11622p 2%FCXCN12201C11747u/16FCCE100000C11847u/16FCC
23、E100000C11947u/16FCCE100000C120C100n/63VFCCDK11000C12247u/16FCCE100000C123100nFCXCN41000C124100nFCXCN41000C1253300u/35FCCE213300C1262200u/35VFCCE212200C1274700u/100FCCE331525C1284700u/100FCCE331525C1294700u/100FCCE331525C1304700u/100FCCE331525C13147u/50FCCE250470C13247u/50FCCE250470C1334700u/100FCCE
24、331525C1344700u/100FCCE331525C13518nFCXCN40180C13618nFCXCN40180C137180nFCXCN41800C138180nFCXCN41800C13918nFCXCN40180C14018nFCXCN40180D101BAS28FCXDDBAS28D103BAS28FCXDDBAS28D105BAS28FCXDDBAS28D107BAS28FCXDDBAS28D108B250C1000FCREC25100D109FB3506FCREC35060D110BAS16FCXDDBAS16D1111N4007FCXDD40070D1121N400
25、7FCXDD40070D113BAS16FCXDDBAS16F101 FOR 230VT10AFCFUS60100F101 FOR 115VT16AFCFUS60400HS100HEAT SINKFCRAD11515REFERENCEVALUECODEREFERENCEVALUECODEPARTS LISTPRINTED CIRCUIT 11.0774-01.04PRINTED CIRCUIT 11.0774-01.04model:EP03-99C&DECLER40-0048-0101 EP03-99c&d.xlsSHEET 1 OF 3REFERENCEVALUECODEPRINTED CI
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