Circuit Description; Components Description - Kenwood KGP-2A Service Manual Supplement

KGP-2A/2B
1. Power Supply Circuit
The KGP-2A/2B power supply circuit uses a dedicated
regulator IC for each circuit application so that the circuits
do not interfere with each other. (Figure 1)
2. Digital Control Circuit
■ GPS module (KGP-2A only)
The location data is measured by the internal GPS mod-
ule. When the KGP-2A is turned OFF, it enters the backup
mode and the power is supplied by the internal rechargeable
lithium battery. It takes approximately 40 seconds to calcu-
late the location data when the KGP-2A is "cold" started (full
initializing).
Control Unit (X53-3980-XX)
Ref. No. Use / Function
IC1 Reset IC
IC3,4 Regulator
IC6 RS-232C driver
IC7 Regulator
IC9 Extended I/O
IC10,11 Regulator
IC12 Shift register
IC13 Regulator
IC14 Reset IC
IC15 EEPROM
IC16 Amplifi er
IC17 CPU
IC18 D/A converter
IC19 Level converter
IC20,21 Level converter
IC22 CODEC IC
IC23 Gate IC
IC24 Gate IC
IC25 Memory IC
IC26 Ampifi er
IC28 Clock demultiplier for DSP
IC29 DSP IC
IC31 Level converter
8

CIRCUIT DESCRIPTION

COMPONENTS DESCRIPTION

Operation / Condition
Monitor of SB power supply voltage
8V (1A)
Level converter 5V↔RS-232C
5V (500mA)
Radio control, Serial/parallel conver-
sion
3.3V
LED (D26~28) control, Power
switch of GPS module
1.8V
Monitor of CPU power supply voltage
Memory backup
Input data
16 Bit
5V↔3V
5V→3V
A/D,D/A conversion
IC19 direction control
A19 (IC17) Logic inverter
3.3V FLASH ROM
Output data
5V→3V
IC3
SB 8V
IC4
8V
Fig. 1
Ref. No. Use / Function
IC32 Amplifi er Microphone input signal
IC34 Regulator 3.3V
Q1,2 Switching Level converter 3V→5V
Q4 Switching Power switch of GPS module
Q5,6 Switching Output terminal open-collector
Q7,8 Switching Output terminal open-collector
Q10~14 Switching Level converter 3V→5V
Q15 Switching Logic inverter
Q16~26 Switching Level converter 3V→5V
Over current
D1 0.75A
protection
Backward voltage
D2
protection
Reverse current
D5
protection
D7~9 Surge absorption
D12 Surge absorption
Reverse current
D18
protection
D24 Surge absorption
D26 LED DC SOURCE (Power)
D27 LED GPS
D28 LED DATA (TX/RX)
Reverse current
D30
protection
D31~48 Surge absorption
D50~62 Surge absorption
IC10
3.3V DSP I/O
3.3V
(KGP-2B CPU)
IC13
1.8V 1.8V DSP Core
IC7
5V analog
5V
(KGP-2A CPU)
IC11
GPS module
3.3V
3.3V analog
IC34
GPS module
3.3V
VANT
Operation / Condition