Dc-Dc Unit - Icom IC-7800 Service Manual Addendum

11-30 DC-DC UNIT

DC-DC UNIT
J4
LG_PWR
GND
- 12V
+15V
+15V
to LOGIC
+15V
unit J820
+8V
+5V
+3R3V
GND
J3
GND
VDD1R5
VDD3R3
to LOGIC VDD5
unit J821 PWRS
C15V
GND
J2
GND
VDD5
GND
+3R3V
+3R3V
+3R3V
to MAIN
+5V
unit J450
+8V
+15V
- 12V
GND
J5
+15V
+15V
to PA 200W
GND
unit J450
GND
HF50ACC322513
VDD3R3
BLM31PG121SN1
BLM31PG121SN1
+3R3V
MESUREMENT CONDITIONS
voltage at RX
frequency: 14.1 MHz
mode: J3E(USB)
ANT(RX): no input
(TX): no modulation Explanatory notes
Digital tester
range: input impedance
VOLTAGE LINE
200mV: 100MΩ
2V: 11MΩ
20V,200V,1000V: 10MΩ
LG_PWR
- 12V
+15V
+8V
+5V
VDD1R5
PWRS
C15V
VDD5
IC21
LM2673S
3.28V
L21
7.95V
L22
15µ
L23
33µ
IC41
LM2673S
L44
3.28V
L41
7.89V
L42
15µ
L43
33µ
LG_PWR
- 12V
+15V
+8V
+5V
VDD1R5
VDD5
VDD5
H8V
VDD1R5
+8V H8V
- 12V
FRONT SW ON: 1.92V
OFF: 0V
+15V
C15V C15V
RL142
AW3023
D141
DAN222
PWRS
FRONT SW ON: 20.7mV
C15V
OFF: 15.1V
L141
10µ
Q141
DTD113ZK
FRONT SW ON: 20.7mV
OFF: 0V
+15V
IC61
LM2673S
4.96V
L61
HF50ACC322513
+5V_ 7.98V
L62
CDRH104R
IC81
LM2673S
4.97V
L81
HF50ACC322513
7.98V
VDD5
L82
CDRH104R
IC101
LM2673S
1.54V 1.21V
L101
R101
HF50ACC322513 270
L102
33µ
H8V
14.8V
197mV
IC121
LM2594M
1 8
2 7
3 6
R122 C122
4 5
0.1
47k
-11.8V
- 12V - 12V
D122
MBRD835LT4
11 - 29
LG_PWR
W1
+8V GND 12
GND
LG_PWR 6
LG_PWR
GND 11
C15V C15V 5
C15V GND 10
GND C15V 4
to
GND GND 9
REG unit
GND H8V 3
GND GND 8
15.1V
H8V H8V 2
H8V NC 7
NC 1
H8V
8.0V
+15V
L63
33µ
L83
H8V
33µ
7.97V
L103
D10F-A814AY
H8V
H8V
L122
D10F-A814AY
D123
RB081L
+15V