Sony DIGITAL BETACAM DVW-707 Maintenance Manual page 113

(6) Servo Control Block
(SV-210 board, SE-210 board, CTL-10 board,
and HN-260 board (2/2))
SV-210 board
The SV-210 board mounts two MPUs. MPU1 controls the
mode control and capstan servo control while serial-
communicating with the System Control CPU. MPU2
controls the drum servo control while interfacing with
MPU1. A drum motor and capstan motor are controlled by
the PWM switching drive based on the feedback servo of
the FG/PG pulses and the FG/CTL pulses, respectively. A
threading motor is controlled by a bi-directional motor
driver.
DVW-790WS/709WS/707
DVW-790WSP/709WSP/707P P1
(7) Power Supply Block
(CNB-11 board (2/2), RE-160 board and RE-161
board)
CNB-11 board (2/2)
The input DC 12 V from the battery pack or DC IN
connector is input to the CNB-11 board (2/2) where the
input 12 V passes through a breaker and the POWER
switch, then it is output as an UNREG +12 V.
This output voltage is sent not only to the camera and VTR
blocks but also to the RE-160 board.
RE-160 and RE-161 boards
The RE-160 and RE-161 boards make up a DC-DC
converter.
The UNREG +12 V supplied from the CNB-11 board
(2/2) is converted to the various output DC voltages which
are sent to the camera and VTR.
The converter system uses an highly efficient synchronous
type PWM switching regulator system.
The PWM switching regulator is equipped with a short-
circuit protection circuit which turns off all outputs when
any of the output power is shorted to GND. The PWM
switching regulator is also equipped with the cut-off circuit
which shuts down the output power when the input voltage
is decreased below the guaranteed operating voltage.
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