Muratec F-110 Field Engineering Manual page 68

4-4-2-10. THV(THV(+)/THV(-) Output Unit)
Transfer(+) output unit is the transfer output control signal 'PWM-LOW ACTIVE'.
When THV-PWM LOW signal is received, Q203 turns on and the steady voltage will be accepted to the non-inverting terminal
of OP-AMP 324. As the voltage is higher than the inverting reference voltage of OP-AMP, OP-AMP output turns high.
The 24V power adjusts the electric potential to ZD201 and ZD202, sends IB to TRANS auxiliary wire through current-restrict-
ing resistance R215 via R212 and C204, and eventually Q204 will turn on. When the current is accepted to Q402, Ic increas-
es to the current proportional to time through the T201 primary coil, and when it reaches the Hfe limit of Q204, it will not retain
the "on" state, but will turn to "off". As Q402 turns 'off', TRANS N1 will have counter-electromotive force, discharge energy to
the secondary coil, sends current to the load and outputs THV voltage through the high voltage output enable, which is com-
prised of Regulation– circuit. The output voltage is determined by the DUTY width. Q203 switches with PWM DUTY cycle to
fluctuate the output by fluctuating the OP-AMP non-inverting end VREF electric potential, and the maximum is output at 0%
and the minimum, at 100%.Transfer(-) output unit is THV-EA 'L' enable.
When THV-EA is 'L', Q302 turns on and the VCE electric potential of Q302 will be formed and sends IB to TRANS auxiliary
wire through R311, C305 and VR302 via current-restricting resistance R314, and eventually Q303 will turn on. When the cur-
rent is accepted to Q303, Q303's Ic increases to the current proportional to time through the T301 primary coil, and when it
reaches the Hfe limit of Q303, it will not retain the "on" state, but will turn to "off". As Q303 turns 'off', TRANS N1 will have
counter-electromotive force, discharge energy to the secondary coil, send current to load and output THV(-) voltage through
the high voltage output enable, which is comprised of Regulation– circuit.
5V
R201
10K
U2
U2
1 2 3
#7 TEV-PWM
R205
1.8K
24VS
+
C101
35V47 F
U
#17
5V
#19
18V
5
TEV-EA
#5
7
D-GND
#24 TEV-READ
18V
R206
100
R208
Q203
30K
A708Y
R209
100KF
R207
C202
C201
2K
R210
103 121
VR201
845KF
50K
D301
R3
1N4148
1/2W560
ZD1 C7
104
5.6V
6
U2
7407
24VS
C4
103
10
+
8
U1
R302 R303
9
_
33K 100KF
KA324
C302
D302
102
1N4148
R301
470K
C301
222
24VS
D201
1N4148
5
+
7
R213
U1
2.2K
_
6
D202
11 KA324
R211
1N4148
1MF
R212 C203 D203
ZD201 ZD202
680K
472 1N4148
5.65V 705V
18V
R309
202K
Q301
A708Y
R307
33K
18V
R310
2.2K
Q302
A708Y
R308
33K
R304 R306
R311
389KF
26.1KF
100KF
C303
103 R305
10KF
C304
500V103Z
VR301
5K
T201
C206
KAB-007
3KV470pF
1 7
C205
2KV68pF
5 6
Q204 2
D526
4
C204
R215
R214
333Z 390
2.2K
R312
1W56
KAB-006
C307
T301
3KW470pF
1
6
R313
1W56
C306
2KV68pF
5
7
Q303
2
D526
VR302
2K
4
C305
R314
333Z
1.7K
Circuit Description
D204
D205
4KV 4KV
C207
3KV470pF
R216 R218
SBR306 MGR1/2W100KF
R217
SBR207
D304
4KV
D303
C308 R315
4KV 3KV470pF SBR306
4-35