Icom IC-7000 Service Manual - Page 14

3-5-2 MAIN UNIT VOLTAGE LINE Line Description 3.3 V Common 3.3 V converted from the 5 V line by the 3.3 V regulator circuit (IC1801). The output voltage is applied to the D/A converter ICs (IC2151-IC5155), etc. Common 5 V converted from the H V line by the 5 V regulator circuit (IC1951). The output 5 V voltage is applied to the CODEC IC (LOGIC unit; IC551), low-pass filters (LOGIC unit; IC451, IC502), etc. Common 8 V line converted from the HV line by the 8 V regulator circuit (IC1901). 8 V The output voltage is applied to the buffer amplifiers (IC2101-IC2103), analog switches (IC2156, IC2251), etc. Transmit 8 V controlled by the T8 regulator circuit (Q1703, Q1704) using TXS signal T8 from the CPU (LOGIC unit; IC1302, pin 106). The output voltage is applied to the RF switch (Q101), 2nd IF amplifier (Q701), 3rd IF amplifier (Q901), etc. Receive 8 V controlled by the R8 regulator circuit (Q1701, Q1702) using RXS signal R8 from the CPU (LOGIC unit; IC1302, pin 105). The output voltage is applied to the 2nd IF amplifier (Q702), 3rd IF amplifier (Q1001), 3rd mixer (Q1101), etc. 3-6 PORT ALLOCATIONS 3-6-1 SUB-CPU (DISPLAY UNIT; IC2003) Pin Port number name Description 3, 5 MDBK, MDAK Input ports for [DIAL]. 13, 14 S1AK, S1BK Input ports for [PBT2/M-ch] control. 15, 16 S2AK, S2BK Input ports for [PBT1/RIT] control. 21 VRK Input port for [AF] switch. 22 PBTK Input port for [PBT/M-ch] switch. 23 TUNK Input port for [TUNER/CALL] key. 24 TSK Input port for [TS] key. 25 LCKK Input port for [LOCK] key. 26 BUPK Input port for [Y(BAND)] key. 27 BDNK Input port for [Z(BAND)] key. 28 FMSL Input port for the HM-151 connection detection. 35 PHNK Input port for the headphones connection detection. 37 LCK Outputs clock signal for the LCD driver (IC506). Pin number 38 39 47 48 54 55 56 57 58 70 71 73 74 75 77 78 79 80 Port name LDT LDST FSQS RXD BLV KLV TXD PBT1D PBT2D LRXD LTXD AFGL SQLL PTTL FUDL KI0L KI1L KI2L Description Outputs data signal for the LCD driver (IC506). Outputs strobe signal for the LCD driver (IC506). Outputs the squelch control signal. High: Squelch is opened. Outputs the RX LED control signal. High: While receiving or squelch is opened. Outputs the dimmer control signal for the LCD backlights. Outputs the dimmer control signal for the key backlights. Outputs TX LED control signal. Low : While transmitting. Outputs control signal for [PBT/M-ch/ RIT] indicator. Low : While the RIT function is ON. Outputs control signal for [PBT/M-ch/ RIT] indicator. Low : While the PBT function is ON. Input port for data signal from the main CPU (LOGIC unit; IC1302). Outputs data signal to the main CPU (LOGIC unit; IC1302). Input port for [AF] control. Input port for [RF/SQL] control. Input port for PTT control signal from the microphone that is connected to the FRONT unit. Input port for [UP] and [DN] switches from the optional microphone (HM-103, SM-20) that is connected to the FRONT [MIC] connector. Input port for [MODE], [P.AMP/ATT], [Y(MENU/GRP)] and [Z(MENU/ GRP)] keys. Input port for [F-1], [F-2], [F-3] and [F-4] keys. Input port for [NB LEV], [NR LEV], [N/ ANF] and [SET/REC] keys. 3 - 9