DS90LV031B datasheet(5/10 Pages) NSC

Part #	DS90LV031B

Description	3V LVDS Quad CMOS Differential Line Driver

Download	10 Pages

Scroll/Zoom	100%

Manufacturer	NSC [National Semiconductor (TI)]

Direct Link	http://www.national.com

Logo

5 / 10 page

Parameter Measurement Information (Continued)

Typical Application

Applications Information

General application guidelines and hints for LVDS drivers

and receivers may be found in the following application

notes: LVDS Owner’s Manual (lit #550062-001), AN808,

AN977, AN971, AN916, AN805, AN903.

LVDS drivers and receivers are intended to be primarily used

in an uncomplicated point-to-point configuration as is shown

in

Figure 6. This configuration provides a clean signaling en-

vironment for the quick edge rates of the drivers. The re-

ceiver is connected to the driver through a balanced media

which may be a standard twisted pair cable, a parallel pair

cable, or simply PCB traces. Typically, the characteristic dif-

ferential impedance of the media is in the range of 100

Ω.A

termination resistor of 100

Ω should be selected to match the

media, and is located as close to the receiver input pins as

possible. The termination resistor converts the current

sourced by the driver into a voltage that is detected by the re-

ceiver. Other configurations are possible such as a

multi-receiver configuration, but the effects of a mid-stream

connector(s), cable stub(s), and other impedance disconti-

nuities as well as ground shifting, noise margin limits, and to-

tal termination loading must be taken into account.

The DS90LV031B differential line driver is a balanced cur-

rent source design. A current mode driver, generally speak-

ing has a high output impedance and supplies a constant

current for a range of loads (a voltage mode driver on the

other hand supplies a constant voltage for a range of loads).

Current is switched through the load in one direction to pro-

duce a logic state and in the other direction to produce the

other logic state. The output current is typically 3.5 mA, a

minimum of 2.5 mA, and a maximum of 4.5 mA. The current

mode requires (as discussed above) that a resistive termi-

nation be employed to terminate the signal and to complete

the loop as shown in

Figure 6. AC or unterminated configu-

rations are not allowed. The 3.5 mA loop current will develop

a differential voltage of 350 mV across the 100

Ω termination

resistor which the receiver detects with a 250 mV minimum

differential noise margin neglecting resistive line losses

(driven signal minus receiver threshold (350 mV – 100 mV =

250 mV)). The signal is centered around +1.2V (Driver Off-

set, V

OS) with respect to ground as shown in Figure 7. Note

that the steady-state voltage (V

SS) peak-to-peak swing is

twice the differential voltage (V

OD) and is typically 700 mV.

The current mode driver provides substantial benefits over

voltage mode drivers, such as an RS-422 driver. Its quies-

cent current remains relatively flat versus switching fre-

quency. Whereas the RS-422 voltage mode driver increases

exponentially in most case between 20 MHz–50 MHz. This

is due to the overlap current that flows between the rails of

the device when the internal gates switch. Whereas the cur-

rent mode driver switches a fixed current between its output

without any substantial overlap current. This is similar to

some ECL and PECL devices, but without the heavy static

I

CC requirements of the ECL/PECL designs. LVDS requires

about 80% less current than similar PECL devices. AC speci-

fications for the driver are a tenfold improvement over other

existing RS-422 drivers.

DS101311-7

FIGURE 5. Driver TRI-STATE Delay Waveform

DS101311-8

FIGURE 6. Point-to-Point Application

www.national.com

5

Similar Part No. - DS90LV031B

Manufacturer	Part #	Datasheet	Description
National Semiconductor ...	DS90LV031B	545Kb / 9P	3V LVDS Quad CMOS Differential Line Driver
	DS90LV031BTM	545Kb / 9P	3V LVDS Quad CMOS Differential Line Driver
	DS90LV031B	545Kb / 9P	3V LVDS Quad CMOS Differential Line Driver

More results

Similar Description - DS90LV031B

Manufacturer	Part #	Datasheet	Description
National Semiconductor ...	DS90LV031B	545Kb / 9P	3V LVDS Quad CMOS Differential Line Driver
	DS90LV031A	181Kb / 11P	3V LVDS Quad CMOS Differential Line Driver
	MNDS90LV031A-X	191Kb / 9P	3V LVDS Quad CMOS Differential Line Driver
Texas Instruments	DS90LV031AQML	347Kb / 15P	[Old version datasheet] 3V LVDS Quad CMOS Differential Line Driver
National Semiconductor ...	DS90LV047A	268Kb / 12P	3V LVDS Quad CMOS Differential Line Driver
STMicroelectronics	STLVDS47	189Kb / 10P	3V LVDS QUAD CMOS DIFFERENTIAL LINE DRIVER December 2002
National Semiconductor ...	DS90LV047A	322Kb / 13P	3V LVDS Quad CMOS Differential Line Driver
Texas Instruments	DS90LV047ATMX	1Mb / 21P	[Old version datasheet] DS90LV047A 3V LVDS Quad CMOS Differential Line Driver
	DS90LV031AQML	249Kb / 14P	[Old version datasheet] DS90LV031AQML 3V LVDS Quad CMOS Differential Line Driver
	DS90LV031ATM-NOPB	912Kb / 19P	[Old version datasheet] DS90LV031A 3V LVDS Quad CMOS Differential Line Driver

More results

DS90LV031B Datasheet(PDF) 5 Page - National Semiconductor (TI)

DS90LV031B Datasheet(HTML) 5 Page - National Semiconductor (TI)

Similar Part No. - DS90LV031B

Similar Description - DS90LV031B

Html Pages

1 2 3 4 5 6 7 8 9 10

Datasheet Download

Link URL