Vertical Output - Sony CPD-G400 Training Manual

Vertical Output

Vertical Stages
The vertical stage consists of three ICs:
IC IC Number
Name
CPU IC1001 Main D board
(not behind bezel.
shown)
DPU IC801 Small N board
on the D
board.
Vertical IC401 On a heat sink
Output near the FBT.
Vertical Oscillator
CPU IC1001 houses the vertical oscillator. It runs as long as there is
Standby +5V applied. The vertical oscillator free runs at 80 Hz and is
locked to sync when input from the computer.
Location Function
1. V Oscillator free runs at
80Hz or locked to input
sync.
2. CRT protection -
Monitors V Output
voltage (VFBP).
1. V Drive
2. Sets vertical size (saw
amplitude)
3. Limited range DC
centering
Vertical Amplifier
Vertical Flyback voltage
boost circuit is monitored
by the CPU for protection.
53
Inputs
CPU 1. V Sync (not required
IC1001 for an output)
2. Standby +5V
3. 8Mhz Xtal
4. VFBP V
signal for shutdown
protection
Vertical Drive
The DPU IC801 serves as the vertical driver. Input are positive vertical
pulses and output are sawtooth pulses and a DC reference voltage (DCC2).
The sawtooth signal is also used for convergence and geometry control
within IC801 (not shown).
In p u t
D P U + O s c illa to r p u ls e s
S e ria l d a ta & c lo c k
Vertical Output
This output amplifier amplifies the signal and supplies sufficient current to
drive the 8.7ohm yoke.
The voltages about IC401 are found in the chart below:
Pin # Function
1 DC ref input 0V
2 B+ +14V
3 Flyback input -13V
4 B- -14V
5 Saw Output 0V
6 Flyback out +14V
7 Saw Input 0V
IC1001
Outputs
Oscillator output
5Vp-p
output
IC 8 0 1
O u tp u t
V S a w to o th p u ls e s
D C o ffs e t v o lta g e
IC401
DC Peak Voltage
Voltage
1Vp-p
25Vp-p
20V saw + 40V
spike
25Vp-p
1Vp-p
@
Wave Shape