Horizontal Deflection Signal Processing - NEC MultiSync FE700 Serviceanleitung

4. Horizontal deflection signal processing

LM1290:
1. Full-automatic synchronization from 22 kHz to 90 kHz. No component changeover nor external
adjustment is required.
2. DC control H phase and duty cycle.
3. The resistance corresponds to the frequency programmable down to VCO.
4. X-ray input invalid.
5. H-drive invalid due to low VCC (when VCC<9.5V). The H OUT transistor is protected as a result.
6. The capacitor protects the H output transistor during the change of the scanning mode, by means of
the programmable frequency ramming H VO/dt.
System Block Diagram
X-RAY 5
SD
V
14
CC
VOLTAGE
V
13
REFERENCE
8
GND
FVC
11
FILTER
FCV
H/HV
H SYNC
3
SYNC
PROCESSOR
2
H/HV POLARITY
Typical Application LM1290
H
POLARITY
OUTPUT
50k
H/HV
SYNC
INPUT
2k
V
CC
10k
DUTY
5k
CYCLE
CONTROL
DISABLE
LATCH
1.8V
PD2
S/H VCO
V DETECT
20k
1 1 1 1 f f f f
0.1µF
MIN
/
H HV
2 2 2 2
POLARITY
/ PD
H HV
3 3 3 3
SYNC
LM LM
LM LM
DUTY
4 4 4 4
1290 1290
1290 1290
CYCLE
5 5 5 5
-
X RAY
0.1µF
6 6 6 6
FLYBACK
7 7 7 7
H DRIVE
DUTY CNTL
4
H DRIVE
1 10
f PHASE
MIN
CNTL
V
CC
+ 100µF
+ 470µF
14 14
V 14 14
0.47µF
CC
3.9k
V 13 13
13 13
REF
1 /
FILTER
12 12 12 12
4.7nF
VCO IN
+
FVC
11 11
11 11
1µF
FILTER
10 10
10 10
PHASE
1µF
+
PD2
9 9 9 9
FILTER
8 8 8 8
GND
0.1µF
8 - 19
7
H DRIVE
9 PD2
FILTER
6
FLYBACK
PD1 FILTER/
12
VCO IN
PD1
3.3k
H PHASE
5k
CONTROL
V
CC
1.2k
H DRIVE
OUTPUT
FLYBACK
PULSE IN
X-RAY
PROTECTION