Service manual

Page 22

MODEL: L423FR

The output format of this IC is LVDS data stream (differential signals).

In 28 bits, 24-bits digital video signal and horizontal sync signal, vertical sync signal, and an enable

signal and a clock signal for LCD panel are pointed out.

A phase-locked transmit clock is transmitted in parallel with the data streams over a fifth LVDS link.

And this output is sent to LCD panel through J402.

(N)IC405 : 4M bit Flash Memory(PM39LV040-70JCE : PMC)

This IC is installed the firmware of IC400(gm1601), helps that IC400(gm1601) serves as another

MPU. (This model operates by 2 MPU)

(O)IC403 : 128M-bit DDR SDRAM( HY5DU283222AQ-5 : HYNIX)

This IC is used as external frame buffer of IC400(gm1601), provides the storage required for the

frame rate conversion process and integrated OSD.

2.2.

Audio circuitsAudio circuits

Audio circuits

It explains the audio circuits and speaker system of L423FR.

Our design spec is as follows.

- High Power outputs : Total 20W(5W*2(L,R) + 10W(woofer))

- 2.1ch Sub woofer speaker system

- Impedance : 6+/-0.9 ohms

- Compact and high performance sound enclosure box (3 pieces).

- Care for minimizing the vibration noise

(Refer to an attached “Audio block diagram of LT-4260”, regarding as the flow of video signal.)

2-1. Audio select circuits

(P)IC601 : Analog-switch IC (CXA2089 : SONY)

In this IC, the audio from COMPONENT(J602), PC(J604), INPUT(J601), DVI(J603),

HDMI(outputs for IC602) is selected by register control of IC601 via

5V IIC-bus5V IIC-bus

5V IIC-bus

2-2. Audio process circuits

(Q)IC610 : Audio processor IC (MSP3440G : Micronus)

This models are used the MSP3440G as the audio processor.

This IC’s functions are as follows.

- Volume control

- Tone control

- Surround

- L/R mixing

- Sub-woofer output

- Audio line output

This model has some sound effect features on user menu, Bass, Treble, Balance, Surround, Level

Sound, Sub Woofer.

Audio adjustment of those in this model is performed by this IC.