AND8020D datasheet(14/18 Pages) AD

14 / 18 page

AND8020/D

http://onsemi.com

SECTION 5. DIODE TERMINATION

VBB

Driver

Receiver

*All Media

Alternative to the resistor network termination schemes,

a Diode method shown in Figure 19 may afford certain

advantages when a design has the following constraints.

1. Impedance controlled media line is not required

(coax, twisted pair, striplines, etc.)

2. Impedance matched termination network is not

required.

3. Overshoot and Noise need to be clamped to logic

HIGH/LOW levels.

Figure 19. Diode Termination

VBB

Driver

Receiver

*All Media

VBB

Driver

Receiver

*All Media

D1 and D2 diodes may be an MBD301, MMBD301,

MBD701, MMBD701LT1, or a dual package MMBD452LT1.

Diode forward voltage curves from a data sheet, such as shown

in Figure 20, will determine specific current and voltage

operation range. Frequency limitations may be a consideration

when selecting the diodes. The Silicon Hot−Carrier Schottky

Barrier diode MBD701, for example, displays a forward Vf of

about 0.55 V and an If of about 11 mA (at 25°C) to match a

W impedance line. At higher temperatures, the current

decreases.

Figure 20. MMBD701 Diode Forward Voltage

0.1

1.0

100

0.2

0.4

0.8

1.2

1.6

2.0

VF, FORWARD VOLTAGE (V)

TA = 85°C

TA =−40°C

TA = 25°C

AND8020D Scheda tecnica(PDF) 14 Page - Analog Devices

AND8020D Scheda tecnica(HTML) 14 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Scheda tecnica Scarica

Link URL