Arcam DiVA CD73 Servis Kılavuzu - Sayfa 5

CD Çalar Arcam DiVA CD73 için çevrimiçi göz atın veya pdf Servis Kılavuzu indirin. Arcam DiVA CD73 13 sayfaları. Compact disc player

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1. Mechanism and Micro Engine

The CPU is located at component position U701 and

can be found on the front panel display board, the

CPU contains a Keyboard scan this is driven from

the resistive array powered by the VREF output at

Pin 98 the voltage drop sensed can be seen on Pin

97 (AVSS) and as 4.9 V on R701.

The CPU also receives and decodes the IR from

both the display board remote receiver and the rear

panel remote input 3.5mm jack.

Please note: The IR from the from the display panel

pickup device is not driven directly into the CPU it

takes a path onto the main board and into the IR

micro circuit the signal is mixed into the rear panel

sourced IR signal by the circuit based around Q301,

Q302, Q303 the result is a signal called RMIN this

signal is fed back to the display board and into Pin 32

of the CPU.

IR RC5 electrical signals driven into the rear panel

3.5 mm jack passed thru the Opto-isolator package at

location OP301 the signal is then clamped to 3v9 by

Zener diode D301 before reaching R-C filter network

provided by C340, C341 and R304 final drive is

supplied by U301(a) and U301(b).

Digital to Analogue conversion

The BCK, PCMD and LRCK lines from the DSP are

buffered by U406 (74HCU04) before arriving at the

D to A converter at location U401 (WM8740) these

lines are now labelled as BCLK, ADATA and

LRCKIN (left, right clock in).

The WMA740 DAC is driven from its own 5 Volt

supply, this can be seen on pin 8 as DVDD.

The de-emphasis flag arrives from the DSP on pin

number 27 (high = on)

The master audio clock arrives at pin 5 labelled at

DACLK and is supplied by the previously mentioned

circuit built around U402

The Audio outputs from the DAC can be seen via

an x10 probe on R416 and R414 Left channel and

R415 and R417 Right channel, these are differential

outputs and as such will have +/- offset respectively.

The differential Audio outputs from the DAC are

summed by U403a and U404a before driving into the

output Op-amps U403b and U404b, D.C errors are

removed by servo Op-amps U405a and U405b

providing a D.C coupled output.

(see page

Optional DAC stage notes

As previously mention the main board has been

designed to provide a platform for other players

within the Diva range and as such provisions

have been made for the addition of optional D to

A stages; these can be connected to the flexi foil

sockets at locations SK203 and SK301 see Fig

3a/b for relevant pin information for these

sockets.

When fitting an optional Audio stage we need to

adjust the jumper settings on the existing main

board information on jumper settings appear

within Fig 4.

Fig 3a Pin connections for SK203.

Pin Number(s)

Power supply and function

Digital ground

2,6,7,12,13,19,20

Analogue ground

3,4,5

+11v unregulated

9,10,11

+5v Digital supply (DAC)

14,15

+5v Analogue supply

16,17,18

-12v Analogue supply

21,22,23

+12v Analogue supply

Fig 3b Pin connections for SK301.

Pin Number(s)

Function

1,2,5-9,18-

Analogue ground

20,23,26,28,30,32.

Emphasis

Reset

Mute

Left/Right clock in (LRCKIN)

A DATA

B-Clock (BCLK)

Fig 4. Option jumper settings.

Location

CD73

PL100

Open

PL202

Open

PL203

Short

PL204

Open

PL205

Short

PL300

1/2 Short

PL300

2/3 Open

PL400

Short

PL401

Short

PL402

Short

PL403

Open

Option

Open

Short

Open

Short

Open

1/2 Open

2/3 Short

Open

Short