Sanyo VPC-CA65EXBL, Руководство по обслуживанию

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1-3. PW1 POWER CIRCUIT DESCRIPTION
1. Outline
This is the main power circuit, and is comprised of the follow-
ing blocks.
Switching controller (IC501)
Motor system power output (L5301)
Digital 3.25 V power output (L5002)
Digital 1.2 V power output (L5003)
Analog -6 V power output (Q5004, L5004)
Analog 12 V power output (Q5005, L5005)
Backlight power output (Q5007, L5007)
Analog 3.4 V power output (IC503)
Digital 1.8 V power output (IC504, L5010)
2. Switching Controller (IC501)
This is the basic circuit which is necessary for controlling the
power supply for a PWM-type switching regulator, and is pro-
vided with seven built-in channels, only CH1 (motor system),
CH2 (digital 3.25 V), CH3 (digital 1.2 V), CH4 (analog -6 V),
CH5 (analog 12 V) and CH7 (backlight) are used.
Feedback for the each power supply output is received, and
the PWM duty is varied so that each one is maintained at the
correct voltage setting level. Feedback for the backlight power
(CH7) is provided to the both ends voltage of registance so
that regular current can be controlled to be current that was
setting.
2-1. Short-circuit protection circuit
If output is short-circuited for the length of time determined
by the condenser which is connected to Pin (1) of IC501, all
output is turned off. The control signal (P ON) are recontrolled
to restore output.
3. Motor System Power Output
5.3 V is output. Feedback for the 5.3 V is provided to the switch-
ing controller (Pin (36) of IC501) so that PWM control can be
carried out.
4. Digital 3.25 V Power Output
VDD3 is output. Feedback for the VDD3 is provided to the
swiching controller (Pin (45) of IC501) so that PWM control
can be carried out.
5. Digital 1.2 V Power Output
VDD 1.2 is output. Feedback for the VDD 1.2 is provided to
the swiching controller (Pin (44) of IC501) so that PWM con-
trol can be carried out.
6. Analog -6 V Power Output
-6 V (A) is output. Feedback for the -6 V (A) is provided to the
swiching controller (Pin (38) of IC501) so that PWM control
can be carried out.
7. Analog 12 V Power Output
+12 V (A) is output. Feedback for the +12 V (A) is provided to
the swiching controller (Pin (39) of IC501) so that PWM con-
trol can be carried out.
8. Backlight Power Output
Regular current is being transmitted to LED for LCD back-
light. Feedback for the both ends voltage of registance that is
being positioned to in series LED are provided to the switch-
ing controller (Pin (42) of IC501) so that PWM control to be
carried out.
9. Analog 3.4 V Power Output
+3.4 V (A) is output. +3.4 V (A) is output to drop 3.4 V by
regulator IC503 from motor system power output.
10. Digital 1.8 V Power Output
VDD 1.8 is output. Feedback for the VDD 1.8 is provided to
the switching controller (Pin (3) of IC504) so that PWM con-
trol to be carried out.