Features

Provides lead

full differential input, output and feedback

Differential input range ± 2.3V

550MHz 3DB bandwidth

1100V/μs conversion rate

20MHz

#8226; single 5V or dual ± 5V power supply

40mA maximum output current

Low-power -12.5ma typical power supply current

Application

Application

Application

Application

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double twisted wire driver

Differential line driver

double twisted line vga

# 8226; ADSL/HDSL driver

Single -end differential release

transmit analog signal in the noise environment

Description

] 550MHz Differential Piece Drive

EL5177 is a high -bandwidth placed, with differential outputs. It is mainly used to drive the twisted pair or any application that may occur. The input signal can be a single -end or differential form, but the output is always different.

On EL5177, the two feedback input provided users with the ability to set the equipment gain (the minimum gain was stable at 1).

The output consensus level is set by reference pin (Ref), and the -3DB bandwidth of the pin is 110MHz. Generally speaking, this pin is grounded, but it can be connected to any reference voltage. The two outputs (OUT+, OUT-) have short-circuit protection to withstand the temporary overload conditions. EL5177 can be used in 10-pin MSOP packaging, and can work within the entire temperature range of -40 ° C to+85 ° C. Order information

Note: Intersil lead -free product uses special lead -free materials; molded compounds/mold connection materials and 100%matte tin tin The panel terminal is compatible with SNPB and lead -free welding operations. The lead-free product of Intersil is classified by MSL according to a lead-free peak return welding temperature, which meets or exceeds or exceeds the lead-free requirements of IPC/JEDEC J STD-020B.

Wiring diagram

typical performance curve

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123]

Simplified schematic diagram

Operation and application information description [123 ] Product description

EL5177 is a wide -band wide, low power consumption, single/differential end to differential output amplifier. It can be used as a single/differential end to differential converter. The closed -loop gain of EL5177 is +1 or larger. The connection gain is 1 and drives 1K Differential load, EL5177's -3DB bandwidth is 550MHz. At the gain of 2, the difference of 200 differential load, the bandwidth is about 130MHz. EL5177 has a power -off function and can reduce power when disabled the amplifier.

EL5177 input, output, and power supply voltage range is designed as a single power supply voltage from 5V to 10V, or working under the division of 5V to 10V. For the power supply of ± 5V, the input covarurative voltage range of the amplifier is -4.3V to 3.4V. The input range (DMIR) between the two inputs is -2.3V to+2.3V. The input voltage range at the REF pin is -3.3V to 3.7V. If the input co -mode or differential model signals exceed the scope of the above regulations, the output signal distortion will be caused.

Under the differential load of 1K Differential load of ± 5V power supply, the output of EL5177 can be swinged from -3.8V to+3.8V. As the load resistance decreases, the output swing is reduced.

Differential mode and co -modular gain setting applied the voltage on the REF pin, which can set the output co -mode voltage, the gain is 1. Differential gain is set by RF and RG networks.

EL5177's gain setting is:

Feedback resistance and gain bandwidth The choice of accumulation

For applications that require +1 gain, no feedback resistance is required. Just short -connect output+pins to the FBP pin and output pin to the FBN pin. For gains greater than +1, the feedback resistance forms a pole with parasitic capacitors at the inverter input terminal. When this pole becomes an hour, the phase margin of the amplifier decreases. This will lead to the peak of the time domain and the frequency domain. Therefore, RF has some maximum values that should not exceed to get the best performance. If a larger radio frequency value must be used, then small electric containers that are connected to the radio frequency in several pickups can help reduce bells and peaks, but it will reduce bandwidth.

EL5177 bandwidth depends on the load and feedback network. For non -+1 gains, RF and RG appear in parallel with loads. When this combination changes, the bandwidth will decrease. Therefore, RF has another minimum value that should not exceed to obtain the best bandwidth performance. For gain +1,RF 0 is the best. For non -+1 gains, the best response is obtained when RF comes between 500 to 1K

For RLD 1K , the gain bandwidth multiplication of EL5177 is 200MHz. For gain ≥5, its bandwidth can be predicted through the following equivalent:

Drive capacitance load and cable

EL5177 can drive 23pf differential capacitors and 1K #8486; Differential load parallel, the peak value is less than 5DB at the time of gain +1. If you need less peak in the application, you can connect a small series resistor (usually between 5 to 50 ) to eliminate most of the peak values. However, this will slightly reduce gain. If the gain setting is greater than 1, you can choose the gain resistor RG to compensate for any gain loss of the additional string of the additional string resistor at the output terminal.

When used as a cable driver, it is recommended to always use double -end connections to achieve non -reflective performance. For these applications, an amplifier output terminal connection connector will beolate the amplifier from the cable and allows a wide range of capacitor drivers. However, other applications may have a high -capacitance load without the back terminal resistor. Similarly, installing a small series resistance at the output end can help reduce the peak.

Disable/power off

EL5177 can be disabled and put it out of high impedance. The shutdown time is about 1.2 μs, and the turnover time is about 130ns. When disabled, the power current of the amplifier is reduced to 1.7 μA, and the IS-usually decreases to 120 μA, which effectively eliminates power consumption. The power outage of the amplifier can be controlled by the standard CMOS signal level of the EN pin. The logic signal of the application is related to VS+pin. Signals that make EN pin float or apply lower than VS+1.5V will enable the amplifier. When the signal at the EN pin is higher than VS+-0.5V, the amplifier will be disabled.

Output driving capacity

EL5177 has internal short circuit protection. Its typical short -circuit current is ± 40mA. If the output is short -term, the power consumption is easy to increase, which will cause components to damage. If the output current has never exceeded ± 40mA, it remains to the maximum reliability. This limit is set by the design of internal metal interconnection.

Power loss

has the high output driving capacity of EL5177. Under certain load current conditions, the absolute maximum temperature of more than 135 ° C may be exceeded. Therefore, it is important to calculate the maximum temperature of the application to determine whether the load conditions or packaging types need to be modified so that the amplifier is maintained in a safe working area.

The maximum power consumption allowed in a component is determined according to the following conditions:

Among them:

tjmax the highest knot temperature

tamax the highest ambient temperature

#8226; θja The thermal resistance of the package

The maximum power consumption generated by IC is the total static power supply current multiply at the total power supply voltage, plus the power generated by the IC due to the load, or: [ 123]

where:

vs total power supply voltage

ismax maximum static power current of each channel [123 123 [123 ]

#8710; vo Maximum output voltage of the application

RLD Differential Dynamic load resistance

# 8226; ILOAD load current

By setting up two PDMAX equations equal, the output current and RLD can be solved to avoid overheating device.

Power bypass and printing circuit board layout

Like any high -frequency device, good printing circuit board layout is necessary for optimization performance. The length of the lead should be as reasonable as possible. The power pipe foot must be bypassed to reduce the risk of oscillation. For normal single power operations, when the VS pin is connected to the ground layer, from VS+to GND, a 4.7μF 钽 capacitor is enough to connect with a 0.1 μF ceramic capacitor. If you want to use a split power supply, the same capacitor should be placed on each power supply foot of the ground. In this case, VS-Pin has become a negative power rail.

In order to obtain good communication performance, parasitic capacitors should be maintained at the minimum value. Avoid using a wire wound, because they have an additional series of inductors. If possible, you should also avoid using sockets. The socket will increase the parasitic inductance and capacitance, which will cause performance damage. To minimize the parasitic capacitor of the reverse input pins in the amplifier. The feedback resistance should be placed in a very close to the input pin. It is recommended to use band -line design technology.

Typical application

When the signal is transmitted through the cable, the high -frequency signal will be attenuated. One way to compensate this loss is to increase high -frequency gain on the side of the receiver.

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