DG308B/309B

Vishay Siliconix

Document Number: 70047

S-52896—Rev. E, 14-Jul-97

www.vishay.com

S FaxBack 408-970-5600

4-7

APPLICATIONS

LM101A

+15 V

–15 V

30 pF

15 V

–15 V

V+

V–

DG309B

50 pF

1000 pF

J202

J500

J507

+15 V

2N4400

–15 V

1 k

W

200

W

5 M

W

5.1 M

W

Aquisition Time

= 25

ms

Aperature Time

= 1

ms

Sample to Hold Offset

= 5 mV

Droop Rate

= 5 mV/s

Logic Input

Low = Sample

High = Hold

–

+

FIGURE 7. Sample-and-Hold

TTL

Control

150 pF

1500 pF

+15 V

DG309B

GND

30 pF

LM101A

+15 V

–15 V

Frequency – Hz

1

10

100

1 k

10 k

100 k

1 M

–40

0

160

120

80

Select

Select

Select

Select

V–

= 100 (40 dB)

1

2

1

2

Max Attenuation =

10 k

W

[ –40 dB

0.015

mF

0.15

mF

–15 V

–

+

40

FIGURE 8. Active Low Pass Filter with Digitally Selected Break Frequency