Summary - NEC MultiSync LCD1920NX User And Service Manual

1.Summary

LCD1920NX is a dual input, multi-frequency and multi mode color TFT LCD monitor. It supports different
resolutions including SXGA, XGA, SVGA, VGA and other various high-resolution modes up to 1280x1024 for
IBM, PC compatibles, Power PC and Macintosh. LCD1920NX uses a TFT LCD panel with a 0.294mm pixel
pitch, providing 16.7 million color image.
As the previous block diagram illustrates, LCD1920NX uses the Analog/Digital Interface Controller (IC02)
ASIC for mode detection and resolution scaling from its preset values. Digital input we use SiL 153B (IC11).
To extract TMDS link. The purpose of the two set of PLL is to provide the clock from multiple horizontal
synchronous frequencies. The AD9884 (IC01), include PLL1 and A/D converters sample clock. PLL2
produces the LCD panel's pixel clock with the TLC2933 (IC03).
Furthermore, each TFT LCD monitor uses the 24LC21 (IC26) chip to provide DDC2B with Analog Plug &
Play, 24C02 (IC14) for digital interface Plug & Play. The DDC data format is EDID v1.3.
Upon receiving video signal input, the Analog Interface Controller (Digital Process and Control System) will
trigger the mode detection function such that the internal controls can use the ROM preset information to
drive the Analog Interface Controller. In addition, the preset values can determine A/D converter clock; LCD
pixel clock; line buffer input/output rate; V-Sync and H-Sync pulse width; back porch and front porch to
provide optimal performance for the TFT LCD monitors.
Digital process and control system allows uses to control OSM menu values to change monitor setting that
includes Auto-SYNC , AUTO-CONTRAST, brightness, contrast, color adjust, H/V position and H size. The
following sections are a breakdown of the TFT LCD display control boards major section.
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