Audio/Video A/V Board, Reset Circuit | Philips DVD963SA guide

Circuit Descriptions and List of Abbreviations

DVD963SA

EN 83

The SACD DSD/DST decoder Furore 2 uses 1.8V for its core and analogue portion, and 3.3V for its interface. The on-board 1.8V linear regulator LF18ABDT and 3.3V linear LD1117DT33 are used to generate 1.8V and 3.3V power supply respectively. The back-end section mainly uses the 1.8V or 2.5V and 3.3V, which depend on which back-end processor is used. The on- board linear regulators LF25ABDT or LF18ABDT are used to generate the 2.5V (or 1.8V) required by the STi55xx.

The front-end section mainly uses the 5V and 12V. An on- board linear regulator LD1117DT33 can be used to generate the 3.3V required by the front-end. The 12V is used by the motor and servo drivers.

Reset Circuit

9.4.2Control

The control of the A/V board is done by I2C-decoder IC7107 (see table below):

Table 9-2 Control lines overview IC7107

Description	Pin	Hi	Lo
CLK_SEL	12	External clock	Internal clock
		(DSD stream)	(PCM stream)

UPSAMPLING	11	No upsampling	Upsampling

DAC_RESET	10	Normal	Reset

CENTER_ON	9	Off	On

SPDIF-MUTE	5	Mute	No mute

Low Voltage Detection 4.5V

STi55xx

	Power On
	Reset	RESETn
	Circuit	RESETn
	Circuit
	Delay 1

Furore 2

192k/96k

4 192k PCM

96k PCM

9.4.3 Video

The analogue video signals from the Mono Board are buffered

before they are fed to the A/V board. The video outputs from

the A/V Board are RGB/YUV, YC, and CVBS. These signals

Low Voltage Detection 4.5V

RSTN

Power On

Reset

Circuit

Delay 2

CLK_STBCTRL

Clock Factory

RES_P	Basic Engine

CL 26532053_018.eps 260402

are also fed to the double SCART board.

9.4.4 Audio

The digital audio signals for Surround, Centre and LFE

(subwoofer) are fed to a 6-channel DAC CS4362 (item 7300,

48-pin LQFP) for the audio output. This DAC accepts both DSD

and PCM data streams.

Figure 9-10 Block diagram of reset circuit

This reset circuit takes care that booting the different devices on the mono board takes place in the correct order. The correct reset order is:

1.The Power On Reset circuit (delay t1) creates a reset signal 'RESETn' to reset the STi55xx and Furore .

2.In the meantime, the Power On Reset circuit (delay t1) creates a reset signal 'CLK_STBCTRL', which is inverted to 'RESETn', to enable the Clock Factory.

3.Then, the Power On Reset circuit (delay t2) generates a reset signal 'RES_P' to reset the Basic Engine.

4.The STI55xx can now reset the Basic Engine via 'RSTN'.

9.4Audio/Video (A/V) Board

This board is the interface panel between the DVD-player and its peripherals.

9.4.1Block diagram

The digital audio signals for Front and Stereo are fed to a high

performance current output DAC AD1955 (item 7301) via a

multiplexer (item 7200) which selects either the direct PCM or

an upsampled data stream (determined by the UPSAMPLING

control line.

The Upsampling is only applicable for CD playback, and the

AD1895 sample rate converter (item 7201) converts the 44.1

kHz/16 bit audio to various formats such as 96 kHz/24 bit or

192 kHz/24 bit.

The bit and word clock, required by the upsampling DAC

AD1955 (item 7301), are derived from the 24.576 MHz master

clock (item7103) via counter (item 7204/7205).

The S/PDIF, only supports digital output upsampling of 96 kHz/

24 bit and is encoded by the digital audio transmitter AK4103

(item7203).

There is a control line from IC7107, called CENTRE_ON, which

is used to switch between the centre channel and front

channels for both SACD- and DVD modes.

See Block diagram A/V Board in chapter 6.