Sony PMW-200, Руководство по обслуживанию

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1-3-7. Power Supply System
RE-298/299/300 Boards
The RE-298, RE-299, and RE-300 boards consist of a power circuit (RE-299/RE-300 boards) and a power control unit
(RE-298 board).
However, a part of low-voltage power supply circuit is mounted on the DCP-56 and DPR-343 boards.
Input power supply (UNREG) system operations
An UNREG power voltage is input and is changed to the EVER power voltage state. The power switch ON/OFF state
can be recognized in this mode.
When the power microcomputer (RE-298 board: IC202) recognizes the power switch ON state, the power
microcomputer controls power of each block according to instructions of the system controller (DPR-343 board:
IC2101).
The ordinary input power (UNREG) value is approx. +11 V to +17 V.
• Battery/EXT-DC inputs
These two inputs cannot be physically connected at the same time. Either one power input is selected and supplied.
• Protection of input overvoltage
When a high UNREG power voltage is supplied, the overvoltage protection circuit is activated at the set value of
+19.5 V and the camera body is shut down. This circuit automatically resumes power when the input power voltage
lowers to +19.5 V or less.
• Protection of input low voltage
When a low UNREG power voltage is supplied, the low-voltage protection circuit is activated at the set value of
+10.5 V by the power microcomputer control and the camera body is shut down.
Once the low-voltage protection circuit is activated, the state is maintained. In that case, therefore, turn off the
power switch and replace the battery pack with a charged battery pack or take other appropriate actions.
• UNREG overcurrent detection
An overcurrent detection circuit consisting of IC100 is provided on the RE-299 board. The set value is approx. 4.3
A. Once overcurrent is detected, the circuit is not automatically reset even after the overcurrent is cleared, and
power must be turned on again.
• Protection of reverse power connection
If reverse input power voltage is supplied, Q102 on the RE-299 board is immediately turned off and the UNREG
power is shut off.
• Power-saving function in the standby state
While the camera power switch is turned off, the power microcomputer (RE-298 board: IC202) enters the sleep
mode to save power. Furthermore, Q107 on the RE-298 board is turned off to reduce current in the control system.
DC/DC converter function
Power supply is grouped into four blocks as shown below.
• CMOS/camera block system (Name: xx_IM)
• Audio/video signal system (Name: xx_DP)
• System controller system (Name: xx_SY)
• Media recording/playback system (Name: xx_MD)
Power in each block is turned on and off according to the power sequence control by the power microcomputer.
Short-circuit protection for each power supply system
Each power system monitors respective output voltages and the protection circuit is configured so that it works for each
block. When a short-circuit is detected even in a single block, entire camera is shut down. The protection circuit is not
automatically reset even after the short-circuit is cleared, and power must be turned on again.
PMW-200/PMW-EX280
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