Sony SNC-WR632C Service Manual page 62

5 VDC generation block
IC2502 generates 5 VDC from 24 VDC that is generated using an AC/DC converter block on a PS-858
board.
IC2501 stops IC2502 when a voltage of 24 VDC is not sufficiently high.
IC2502 starts when a voltage of 24 VDC reaches less than 20 V. 5 V is then output.
4-4. MD-151 Board
Local power block
The local power block generates the voltage, used on the MD-151 board, from 24 VDC input to pin 2 of
CN103 on the MD-151 board.
There are voltages below in the local power block.
. 16 VDC: Used for a motor drive system.
. 7 VDC: Used in an FCB camera block.
. 5 VDC: Used in a motor drive control circuit.
. 3.3 VDC: Used in the microcontroller on a board.
. 5 VDC: Used to drive a fan for cooling an FCB camera block.
A voltage of 5 V is turned on and off using the control signal from a microcontroller so as to control
whether to rotate or stop a fan.
Microcontroller block
32-bit RISC microcontroller
The 32-bit RISC microcontroller incorporates flash ROM with the program stored.
The internal firmware of the microcontroller is automatically upgraded when it differs in version from
firmware that SoC on an SY-416 board manages.
Main roles
. Controls pan/tilt operation using the VISCA command from SoC on an SY-416 board.
. Transfers the command to an FCB camera block when an FCB camera block control command is
received.
. Monitors a temperature using a sensor and controls a fan.
. Measures the internal temperature of a doom using a temperature sensor and operates a fan when the
temperature exceeds the specified value.
. Detects the failure of a fan.
Inter-board communication data superimposing circuit
In a full duplex mode, the microcontroller on an MD-151 board communicates with SoC on an SY-416
board using UART.
Transmit data and receive data are bidirectionally multiplexed using a superimposing driver.
Motor driver block
There are motor driver circuits for driving pan and tilt motors. The motor driver circuits are the same in
circuit configuration.
n
The pan and tilt motors are distinguished for reasons of characteristics.
Data that varies for each motor is written in the microcontroller (IC301) on an MD-151 board. Therefore,
do not change the combination of the MD-151 board and motor.
4-6 (E)
SNC-WR632C/WR602C