Kenwood TS-990S Service Manual

Also see for SP-990: Instruction manual

Contents

TS-990S36CIRCUIT DESCRIPTIONFig. 41 Control circuitIC31Extension port 01IC36Extension port 02IC32Extension port 03IC37Extension port 04IC33Extension port 05IC38Extension port 06IC34Extension port 08IC39Extension port 09IC42Extension port 07IC43Extension port 10IC30Multiplexer3IC35Multiplexer2IC46Main MCUFrequency: 88.4736MHzIC44Reset IC11.0592MHzIC405V3VConverterIC413V5VConverterTTO/TSOTT/TSTTI/TSIIC45OR GATEVBINTUVBINTTypeVersion judgementIBK32.768kHzIC49RTC32KOUTI2CIC47EEPROMIC48Buffer5B33B 33B33B1SS388F5D33B33B33B33B 33B33B 33BRT32SIBKCN3PH2PFrom X43-322CN2PH4PFrom X43-32233SD5ACN1PH4PFrom X43-32214SD14SD33B 33BIC381Scope DSPFrequency: 331.776MHz(Max.333MHz)Core1.2VI/O3.3V24.576MHzSDTI1MCLKSCLKLRCK(96kHz)1.2V 33SDSDTI01.2VDC-DCIC380ScopeMCUFrequency:18.432MHz18.432MHz.IC390Parallel frash(8Mbit)IC389Latch ICIC388Latch IC33SDUARTSPIIC382ADC96kHzIC384OP_AMPDifferentialconversionIC387FilterIC385OP_AMPRef. for OP-AMP33SD 5A 5A 5A5AIC386ADC96kHzCN45333SD 5ACN450CN451LchLch+Lch-Rch33SD 33SD33SD33BIC23.3V Reg.33BTo X53-453X50-323 FFC CN(CN47) X50-323 FFC CN(CN43) X57-827 FFC CN(CN37) X55-313 FFC CN(CN32)X54-385 FFC CN(CN65) X43-322 FFC CN(CN70) X46-339 FFC CN(CN71) X53-453 FFC CN(CN72) X42-343 FFC CN(CN73)33B 33B33B33B33B33BOP_AMPTypeVersion judgement9-4. Scope DSP and Its PeripheryThe scope DSP (IC381) is powered by two supply volt-ages, i.e., 3.3 V (I/O) and 1.2 V (Core). The scope DSP isoperated at a clock frequency of 331.776MHz obtained bydividing 24.576MHz in the scope DSP and multiplying thedivided frequency by 27.The flash memory (IC390) for program storage, latch ICs(IC388 and IC389) for address decoding, and ADCs (IC382and IC386) are connected as peripheral devices for thescope DSP. The scope DSP and the scope MCU are in theSPI communication mutually (at a communication speed ofapproximately 1.15MHz). Drawing data for a single screenis transferred at a cycle of 150 ms to the application MCU(X46-339). Such drawing data is transferred under the SPIcommunication at a speed of approximately 2MHz.9-5. Scope IF SignalA 24kHz IF signal received from the scope unit (X42-343 A/10) passes through the quaternary LPFs (IC384 andIC387), and is converted to a differential signal at a singleend. This signal is applied to the ADC (IC382) and convertedto drawing data in the scope DSP (IC381) (Band scope).Fig. 42 Scope IF signalIC382ADC96kHzIC384OP_AMPDifferential conversionIC387OP_AMPFilterCN453 Lch+Lch-Total fc40kHzFrom X42-343IF signal24kHz9-6. MSCPI signalThe audio signal of the main receiver is received from theDSP unit (X53-453) and input into the ADC (IC386 L chan-nel). The signal is converted to drawing data in the scopeDSP (IC381) (Audio scope).9-7. SSCPI signalThe audio signal of the sub receiver is received from theDSP unit (X53-453) and input into the ADC (IC386 R chan-nel). The signal is converted to drawing data in the scopeDSP (IC381) (Audio scope).