Features

Full differential input, output and feedback

350MHz-3DB bandwidth

1200 伏/micro seconds Conversion rate

-75DB distortion, the frequency is 5MHz

single 5V to 12V operations

minimum output current 50 mia 50 mia

Low-power -36MA total typical power current

provides lead-free (conforms to ROHS)

Application

# 8226; twisted tie driver

Differential line driver

vga on the twisted twisted line

in the noise environment Transmitting analog signal

Three differences in twisted divers

Common -mode synchronous encoding

EL4543

is a high -bandwidth three -difference amplifier, an integrated video integrated video Code of synchronous signals. These inputs are suitable for high -speed videos or other communication signals for processing single -end or differential forms, and the scope input range of the co -mode has been extended to negative, so as to achieve ground reference signals in the application of single power supply. The high bandwidth transmission of the differential signal to the standard twisted twisted or coaxial cables, the harmonic distortion is very low, and the internal feedback ensures the gain and phase balance of the output terminal, thereby reducing the harmonious radiation EMI. Embedded logic encodes the standard video level and vertical synchronization signal to the co -mode of the twisted line, and transmits these additional information without an additional buffer or transmission line. Compared with the discrete line driver, EL4543 can significantly save system costs.

EL4543 can be used for 24 LD QSOP packaging and 20 LD QFN packaging, and is specified in the temperature range of -40 ° C to+85 ° C.

Order information

*20 LD 4X4 QFN, exposed pad 2.7 x 2.7 mm connected to vs ** See TB347 to understand the detailed information about the volume specifications.

Note: These Intersil lead-free plastic packaging products use a special lead-free material group; mold/mold connection material and 100%matte tin panel to increase the fire-E3 final decoration, which meets the ROHS standard, and and with SNPB and lead -free welding operations are compatible. The lead-free product is classified as MSL under the peak of lead-free return welding, which meets or exceeded the lead-free requirements of IPC/JEDEC J STD-020.

Typical performance curve

Operation description and application information Introduction

EL4543 Design to use the composite RGB video signal differential to the twisted line, and at the same time encoding the horizontal and vertical synchronization signals to the same to the vertical synchronous signal to as to Common model output. Therefore, the entire video signal plus synchronization can be transmitted through 3 pairs of twisted pair. When using 5 types of cables, the fourth pair can be used to transmit audio, data or control information. Compared with traditional coaxial cables, a composite video distributed on the standard CAT5 cable can save a lot of costs and labor with relatively low prices and easy to drive the CAT5 cable.

Function description

EL4543 provides three full differential high -speed amplifiers, which is suitable for high -resolution composite video signals on the twisted or standard coaxial cable. The input co -mode range extends to the negative, allowing simple ground reference input to be used with a single power supply. The amplifier provides a fixed gain of +2 to compensate the standard video cable terminal solution. The horizontal and vertical synchronous signals (Hsync and Vsync) are passed to the internal logical coding block, encoding the synchronous information into three discrete signals with three different voltage levels. Usually, in the differential amplifier, the external VREF PIN is used to control the co -mode level of the differential output; in the case of EL4543, each VREF of each of the three internal amplifier channels receives the encoding Hsync and vsync information from the logic encoding block. Signal. The final output consists of three full differential video signals, which are synchronized on the co -mode of the three RGB differential signals. Hsync and vsync can easily be separated from the differential output signal, decodate and transmit it to the video monitor with the RGB video signal.

Synchronous transmission

EL4543 encoded Hsync and Vsync signals on the co -mode output of differential video signals; red, green and blue. Data maps 16, 17, and 18 clearly illustrate the sum of the sum of the common mode voltage that leads to the fixed average DC level of non -communication content, and illustrates the logic level. This eliminates electromagnetic interference radiation that enters any co -mode signal along the 5 -type cable twisted line.

Extra the common mode synchronization and decoding Hsync and vsync

Hsync and vsync can synchronize the voltage from the mode. The relationship between Hsync, VSYNC and 3 co -mold levels are shown in Table 1. Using this simple resistance network at the input terminal of each differential channel, it can easily separate the common modulus level from the differential output terminal of EL4543; see Figure 39.

Two -twisted lineTerminal

The schematic diagram in FIG. 39 illustrates the 50Ω series terminal and 100Ω twisted lines. Note: RCM is a co -mode terminal that allows VCM to measure, and it should not be too small because it loads EL4543; RCM is recommended slightly higher than 100Ω.

Video Transmission

EL4543 is a type of twisted line differential line driver, which is used to transmit video signals through a cable of up to 100 feet. However Signal losses increase with the length of the transmission line, EL4543 will require additional support to balance the videos signal along the long twist wire transmission line. A complete solution is the SXGA video transmission system introduced in the EL4543 data table. Please note that EL9110 contains EL9110, which is used for EL9110, for EL9110 for EL9110 for more than 1,000 feet 5 cable signal balance and co -mode extraction. For more information, please refer to the data table.

Remote video transmission

SXGA video transmission system can transmit red, green, and blue (RGB) videos through 5 cables and synchronize to 1,000 feet. The input of the SXGA video transmission system is the output of the RGB video signal and the video source of SYNC. The signal was originally accepted by EL4543; EL4543 converted the RGB signal input by a single -ended input to three completely differential waveforms, and performed synchronized encoding in the discrete public mode of each color channel, and then driven the signal through a CAT5 cable. This signal is accepted by EL9110, and EL9110 can provide a 6 pole equilibrium for high -frequency and low -frequency signal transmission line loss. Then, while extracting the co -mode component for decoding, the EL9110 converts the differential RGB video signal back to a single -end format. The single -end RGB signal is obtained directly from the output terminal of the EL9110 and prepares for the output device. The co -mode decoder circuit is directly from each receiving co -mode signal from the three EL9110 co -mode output pipes, decoding and sending Hsync and Vsync to the output device.

Synchronous transmission

EL4543 encodes Hsync and vsync signals on the co -mode output of different video signals; red, green, and blue. Data Tap 8 clearly illustrates the sum of the sum of the co -mode voltage that causes the fixed DC level of non -communication content; thereby eliminating EMI interference.

Output drive protection

The internal short -circuit protection settings of EL4543 are usually 60 mAh. If the output is short -term, the increased power consumption will eventually destroy the components. In order to achieve the maximum reliability, the output current should not exceed 60 mAh. The 50Ω series carrying the matching resistor provides additional protection.

Power supply voltage

Although EL4543 can work on the ± 5V split guide rail, the most commonly used single power supply 0V to 5V. It should be noted that the input logic threshold and negative power supplyWhen the pin is related, when EL4543 is driven on the split orbit, the reference logic of the single power supply will not work. The input co -mode range of the amplifier is 0V to 2.3V, and the power supply voltage is 0V to 5V. As the power supply voltage increases, it increases (see Figure 7). The DC level range of the co -mode output is the linear function of the power supply (see Figures 16, 17, 18, and 19). The threshold and enable/disable input of the co -mode input switch are linear functions of the power supply voltage (see Figure 8 and 11). If EL4543 is used together with the ± 5V split orbit, enter the synchronous signal before entering EL4543. The circuit configuration shown in FIG. 40 provides appropriate level offset.

Disable and turn off the power

EL4543 to provide a enable-disable function, turn off the logic input high level in 900ns, open logic input in 212ns in 212ns Low level. Disable the power supply of the amplifier to 1.8mA (positive power supply) and 0MA (negative power supply). Please note that the enable/disable threshold is a linear function of the power level of the power supply. Enable/disabled threshold voltage levels are compatible with standard TTL/CMOS, and refer to the minimum power supply voltage.

Reasonable layout technology

Any key issue of any printing circuit board layout is to establish a healthy " ground plane. The ground plane near the input must be provided to minimize the input capacitance. In addition