Sanyo VPC-PD1EXBK, Руководство по обслуживанию

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1-3. PWA POWER CIRCUIT DESCRIPTION
1. Outline
This is the main power circuit, and is comprised of the follow-
ing blocks.
Switching power controller (IC501)
Digital VDD 3 output system (L5031)
Digital VDD 1.8 output system (L5041)
Digital VDD 1.1 output system (L5021)
Motor system BOOST output system (L5301, D5301)
CMOS system VAA 2.8 output system
2. Switching Power 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 four built-in channels and linear regulator is pro-
vided with one channel.
Only CH1 (BOOST system), CH2, CH3, CH4 (digital system)
and CH5 (CMOS system) are used.
Feedback from BOOST system (CH1) and digital system
(CH2, CH3, CH4) power supply outputs are received, and
the PWM duty is varied so that each one is maintained at the
correct voltage setting level.
Feedback for the CMOS system (CH5) is so that output can
be adjusted to be regulated output.
2-1. Short-circuit protection circuit
If output is short-circuited, all output is turned off after approx.
100 ms. The control signal (P ON) are recontrolled to restore
output.
3. (CH1) BOOST system 5.0 V Output
+5.0 V is output. Feedback for the BOOST 5.0 V output is
provided to the switching controller (Pin (22) of IC501) so that
PWM control can be carried out at the internal circuit.
4. (CH2) Digital 1.1 V Output
+1.1 V is output. Feedback for the VDD 1.1 is provided to the
switching controller (Pin (21) of IC501) so that PWM control
can be carried out at the internal circuit.
5. (CH3) Digital 3.3 V Output
+3.3 V is output. Feedback for the VDD 3.3 output is provided
to the switching controller (Pin (15) of IC501) so that PWM
control can be carried out at the internal circuit.
6. (CH4) Digital 1.8 V Output
+1.8 V is output. Feedback for the VDD 1.8 output is provided
to the switching controller (Pin (4) of IC501) so that PWM
control can be carried out at the internal circuit.
7. (CH5) CMOS +2.8 V (A) Output
+2.8 V is output. Feedback for the VAA 2.8 output is provided
to the switching controller (Pin (10) of IC501) so that regula-
tor output control can be carried out at the internal circuit.