DG534A/538A

Vishay Siliconix

www.vishay.com

14

Document Number: 70069

S-05734—Rev. G, 29-Jan-02

PIN DESCRIPTION

Pin Number

Symbol

DG534ADJ

DG538A

Description

2

2

Analog Output/Input

V+

3

3

Positive Supply Voltage

4

4

Analog Input/Output

6

6

Analog Input/Output

–

8

Analog Input/Output

–

10

Analog Input/Output

4/2

7

–

4 x 1 or 2 x 2 Select

8/4

–

11

8 x 1 or 4 x 2 Select

RS

8

12

Reset

WR

9

13

Write command that latches A, EN

11, 10, –

16, 15, 14

Binary address inputs that determine which channel(s) is/are connected to the out-

put(s)

EN

12

17

Enable. Input/Output, if EN = 0, all channels are open

I/O

13

18

Input/Output control. Used to write to or read from the address latches

14

19

Logic Supply Voltage, usually +5 V

–

20

Analog Input/Output

–

22

Analog Input/Output

15

24

Analog Input/Output

17

26

Analog Input/Output

V–

18

27

Negative Supply Voltage

19

28

Analog Output/Input

GND

1, 5, 16

1, 5, 7, 9, 21, 23, 25

Analog and Digital Grounds. All grounds should be connected externally to optimize

dynamic performance

APPLICATIONS

Device Description

The DG534A/538A D/CMOS wideband multiplexers offer

single-ended or differential functions. A 8/4 or 4/2 logic input

pin selects the single-ended or differential mode.

To meet the high dynamic performance demands of video,

high definition TV, digital data routing (in excess of 100 Mbps),

etc., the DG534A/538A are fabricated with DMOS transistors

configured in ‘T’ arrangements with second level ‘L’

configurations (see Functional Block Diagram).

Use of DMOS technology yields devices with very low

high frequency signal handling and higher switching speeds,

while maintaining low insertion loss figures. The ‘T’ and ‘L’

switch configurations further improve dynamic performance

by greatly reducing crosstalk and output node capacitances.

The

DG534A/DG538A

are

improved

pin-compatible

replacements for the non-A versions. Improvements include:

higher current readback drivers, readback of the EN bit,

latchup protection

Frequency Response

A single multiplexer on-channel exhibits both resistance

This RC combination

causes a frequency dependent attenuation of the analog

signal. The –3-dB bandwidth of the DG534A/538A is typically

500 MHz (into 50

W). This figure of 500 MHz illustrates that the

switch-channel cannot be represented by a simple RC

combination. The on capacitance of the channel is distributed

along the on-resistance, and hence becomes a more complex