Power Supply Circuits; Port Allocations - Icom IC-R2 Service Manual

4-3 POWER SUPPLY CIRCUITS

VOLTAGE LINE
DESCRIPTION
LINE
The voltage from the attached battery.
BATT
Common 13 V converted from BATT line by the
DC-DC convertors (IC10 and D3, D5, D15). The
VP
output voltage is applied to the PLL circuit (RF
unit).
Receive 3V controlled by the R3V regulator cir-
R3V
cuit (Q4) using the "RX" signal from CPU (IC11).
Common 3V converted by the +3S regulator cir-
cuit (Q3, Q39) using the "+3SC" signal from CPU
+3S
(IC11).
Common 3V converted by the +3V regulator cir-
cuit (Q6) using the "POWERC" signal from CPU
+3V
(IC11).

4-4 PORT ALLOCATIONS

4-4-1 CPU (LOGIC UNIT IC11)
Pin Port
number name
1 ADJ
2 ATT
3 K2
4 K1
5 AMUTE
6 BATT
7 RSSI
8 RTONE
9 TRC
10 FSET
11 CTON
12 SQL
13 KFUNC
14 KTS
15 VRC
16 DCK
17 AM
18 WFM
21 BEEP
22 DUD
23 POWER
24 AFON
25 DBL1
4 - 4
Description
Output control signal for the adjust-
ment mode.
Outputs RF attenuator control signal
to attenuator switch.
Input port for [LOCK], [BAND], [V/M]
switches.
Input port for [UP], [DOWN] switches.
Output AF mute switch (LOGIC unit;
Q37) control signal.
LOW : While squelched.
Input port for the Low battery detec-
tion.
Input port for the RSSI signal from the
FM IF IC (RF unit; IC2, pin12) to
detect receiving signal strength.
Input port for the receiving tone signal.
Outputs control signal for the tunable
band-pass filter.
Outputs control signal for the RIT fre-
quency.
Outputs control signal for the CTCSS
requlator circuit.
Pulse signal input port for the squelch.
Input port for the [FUNC] switch.
Low : While [FUNC]
pushed.
Input port for the [TS] switch.
Low : While [TS] switch is pushed.
Outputs level control signal for AF vol-
ume.
Input port for the DOWN signal from
the [DIAL].
Outputs AM mode select signals.
Low : When AM is selected.
Outputs WFM mode select signals.
Low : When WFM is selected.
Outputs beep audio signals.
Input port for the UP signal from the
[DIAL].
Input for the [POWER] switch.
Low : While [POWER] switch is
pushed
Outputs control signal for the AF
amplifier requlator circuit.
High : Activates the AF amplifier cir-
cuit.
Outputs control signal for the 1st dou-
bler circuit.
Low : Activates the 1st doubler cir-
cuit.
switch is