Sony LMT-300, Service Manual

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4-4 (E)
LMT-300
4-9. CN-3058 Board
Two fans are connected to the CN-3058 board, which mounts two coin batteries. The fan rotation and
battery voltage are monitored using an I
2
C interface (IC2) and voltage monitoring circuit (consisting of
IC100 and IC101). The obtained status information is sent to CPU on the PU-131 board. Mounted battery
BT100 is used for the PU-131 board, and BT101 is used for the SSP-27/27A board. The redundancy of
batteries is realized by mounting fan units A and B including the CN-3058 board.
m
.
The PU-131 or SSP-27/27A board mounts a circuit that stores data using a battery mounted in CN-3058
board. Therefore, do not pull out two fan units simultaneously while the power of this unit is off.
.
A battery voltage cannot be normally monitored when coin batteries are not mounted or when the coin
battery voltage is low extremely. Replace four coin batteries immediately when the voltage monitoring
alarm of this unit is output. (Refer to Section 3-4-3.)
4-10. CP-406 Board
The CP-406 board has a function that interfaces with external dedicated equipment. It is connected to a
UPS serial control system (CN201), an audio serial control system (CN203), STATUS LIGHT (CN204),
and DCOUT (CN205) using connectors on the front panel. PLD (IC102) always communicates with SMS
CPU through FPGA (IC1602) on the PU-131 board so as to control the whole system.
4-11. IO-243 Board
The IO-243 board has a GPIO control interface function. Six GPO systems and four GPI systems are
mounted on one IO-243 board. Three IO-243 boards are connected to the MB-1143 board. PLD (IC102)
always communicates with SMS CPU through FPGA (IC1602) on the PU-131 board so as to control the
whole system.
4-12. Power Unit
This unit mounts one power unit that supplies power to each board. A power switch is provided on the
rear panel. It can turn on and off
+
12 VDC that is output from the power unit. One power unit (option)
can be added to obtain redundant con fi guration.