Kenwood TS-990S Service Manual

TS-990S
50
COMPONENTS DESCRIPTION
Ref. No. Use/Function Operation/Condition/Compatibility
D280~288 Protection Surge protection
D360
Reverse voltage
prevention
Surge protection
CONTROL UNIT (X53-452X-XX)
Ref. No. Use/Function Operation/Condition/Compatibility
IC1
1.2V switching
regulator
Power supply for 1.2V
(Scope DSP internal (core) sup-
ply)
IC2
3.3V linear regu-
lator
Power supply for 3.3V
(Main MCU power supply)
IC30 Multiplexer For PCB version
IC31~34 Latch IC Extension port of main MCU
IC35 Multiplexer For type and PCB version
IC36~39 Latch IC Extension port of main MCU
IC40
Level converter
(5V

3.3V)
For external antenna tuner signal
IC41
Level converter
(3.3V

5V)
For external antenna tuner signal
IC42,43 Latch IC Extension port of main MCU
IC44 Reset IC System reset
IC45
Level converter
(5V

3.3V)
USB connection detection
IC46 MCU Main MCU
IC47 EEPROM EEPROM for backup
IC48 Buffer For serial clock and data
IC49 Real time clock Real time clock
IC380 MCU Scope DSP-Sub MCU
IC381 DSP Scope DSP
IC382 A/D converter
A/D converter for band scope IF
signal
IC384,387 OP amplifi er
Active fi lter for band scope IF sig-
nal
IC385 OP amplifi er Reference signal for OP amplifi er
IC386 A/D converter
A/D converter for audio scope
signal (Main RX/ Sub RX)
IC388,389 Latch IC Address decoder for scope DSP
IC390 Flash memory Program for scope DSP
Q380 Switching 3.3V switch
Q381 Switching 3.3V switch
D1 Switching
Catch diode for 1.2V switching
regulator
D30
Reverse current
prevention
For standby switch signal (SS)
D31
Reverse current
prevention
For KEY jack judgement signal
(KYSR)
D32
Reverse current
prevention
For real time clock IC power
D380
Reverse current
prevention
For reduced voltage detection
(BKC)
DSP UNIT (X53-4530-00)
Ref. No. Use/Function Operation/Condition/Compatibility
IC1
1.2V switching
regulator
Power supply for 1.2V
(DSP internal (core) Supply)
IC50 Phone amplifi er Phone output
IC51
Audio power
amplifi er
SP1 (internal SP)/ Ext. SP1
IC52
Audio power
amplifi er
Ext. SP2
IC101 MCU DSP-Sub MCU
IC200,
201
Latch
Address decoder for TXMRX-
DSP
IC202 DSP TX/Main RX DSP
IC203 Flash memory Program for TXMRX-DSP
IC300 DSP Sub RX DSP
IC301 Flash memory Program for SRX-DSP
IC302 Buffer Extension output for SRX-DSP
IC322 Inverter X'tal buffer
IC380 Flip-fl op
A frequency divider for SCLK/
LRCK
IC381 Buffer Buffer for SCLK48K
IC382 Buffer Buffer for LRCK48K
IC383 Buffer Buffer for MCLK48K
IC385 D/A converter
D/A converter for BEEP and
MSCPI signal
IC386 D/A converter
D/A converter for MUANO and
SUANO signal
IC387 D/A converter
D/A converter for MRECI and
SRECI signal
IC388 D/A converter
D/A converter for SAGCV and
SSCPI signal
IC389 A/D converter
A/D converter for MRECO and
SRECO signal
IC390 D/A converter
D/A converter for SP1 and SP2
signal
IC391 D/A converter
D/A converter for MANO and
SANO signal
IC392 A/D converter
A/D converter for SRIF/SFMD
and ANI/UANI signal
IC397 D/A converter
D/A converter for TIF/FMOD and
MAGCV signal
IC398 A/D converter
A/D converter for MRIF/MFMD
and MIC signal
IC399 NAND gate For SCLK96K
IC650 OP amplifi er
Active fi lter for SP1 and SP2
signal
IC651 OP amplifi er
Active fi lter for MANO and SANO
signal
IC652 OP amplifi er
Active fi lter for BEEP signal and
reference voltage of OP amplifi er
IC653 OP amplifi er Active fi lter for MUANO signal
IC654 OP amplifi er Active fi lter for SUANO signal

Kenwood TS-990S Specifications

General

Receiver Type	Triple Conversion Superheterodyne
Antenna Tuner	Built-in automatic antenna tuner
DSP	Yes
IF DSP	Yes
Modes	SSB, CW, AM, FM
Display	7-inch TFT color LCD
Weight	25 kg (55.1 lbs)
Antenna Connectors	SO-239
Power Supply	13.8V DC