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Fig.6 shows power circuit diagram of NS500.
In AC/DC convert blotck, AC input voltage is converted to DC+15V and DC+41V. DC+15V/+41V is distributed to each card.

Base

Trunk#2

MPR/SPR

DSP

RMT

EXP-M

AC/DC

FGPlate

+41 V

+15 V

15V/3.3V

Extension#2

Extension#1

Trunk#1

15V/3.3V

15V/5V

PMIC

15V/5V

USB

Fig.6 Power Circuit Block Diagram

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This unit is switching regulator power supply and supplies DC voltages to DCPU Board (MPR), and optional card (free slot).
PSU (power supply unit) has two outputs (41V, 15V). 15V output is supplied only in DCPU Board (MPR)  and option card. Other
outputs are mainly used as an object for the electric supply to a terminal. 

This circuit consists of the following components and removes the exogenous noise or the noise generated at power supply.
C1, C2: normal mode filter (X condenser)
L1, L2: common mode noise filter
C3, C4: common mode noise filter (Y condenser)

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This circuit consists mainly of the following components and performs DC-AC conversion.
D1: Diode Bridge
C5: Primary Smoothing Condenser

As the main component of this circuit, Z1 protects against exogenous noise such as lightning surge.
Z1: Varistor

Immediately after AC input applies voltage, the following components control inrush current to the Smoothing Condenser.
NTC1, NTC3: thermistor

This circuit consists of the following components and detects AC input.
Main components: D81,D82,R80-R95,Q80,Q81,Q82,PC80
AC voltage commutates through D81, D82.
When AC voltage is over the threshold, Q80, Q81, and Q82 are switched ON to allow AC Detection Circuit to transfer AC input

status to the secondary side AC alarm signal delivery section through PC80

This section describes the main converter circuit which insulates the primary DC voltage and converts the voltage to a Secondary
voltage (41V output).

This main converter consists of the following components; Isolated, and Self-excited Pseudo Resonance Type Converter.
Q1: main switch FET
T101: isolation transformer
IC1: IC controls Q1
PC1: device for transfer control secondary side
Other peripheral circuit

Secondary side output condition is transferred by PC1 to the primary side.
Q1 is switched to ON/OFF in IC1 to control the secondary side voltage.

T101: The output of this isolation transformer is 41V, and is the power supply for output voltage in section 3.

This output consists of the Rectification Smoothing Circuit of D101, C101.
This is the output described in section 3, 15V and 41V output for power supply, and also for battery output as described in
section 4.

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The main converter latch circuit works to prevent output voltage from reaching an abnormally high state.
This circuit uses mainly the latch function of IC1.
When secondary side protection circuit reaches an abnormal state (section 6 protection circuit), the signal is sent to primary side
through PC50.
The main converter latch circuit then works to stop the operation.
To release the latch status, release abnormal state, then switch the AC input OFF and leave for over 60 seconds before restart-
ing AC input again

This section describes the operation of the circuit that converts the main converter output to 15V and 41V.

This separately-excited depressor chopper converter consists mainly of IC202, D204, L201, C209, C210, R212-R214.
Input power supply is 41V output of the Main converter described in section 2.
15V output is supplied by the ON/OFF switching action of IC202, D204 and Smoothing Circuit of L201, C209, C210.
Output voltage is set by the resistance rate of IC202, R212-R214.
Oscillating frequency IC202 is 300kHz(typ).

Operation is protected the IC202 internal Overcurrent Protection Circuit.