TLC7528C, TLC7528E, TLC7528I

DUAL 8BIT MULTIPLYING

DIGITALTOANALOG CONVERTERS

SLAS062E − JANUARY 1987 − REVISED NOVEMBER 2008

11

POST OFFICE BOX 655303

APPLICATION INFORMATION

REFB

19

RFBB

OUTB

AGND

TLC7528

REFA

DB0 − DB7

CS

WR

DACA / DACB

DGND

Vref

Data Inputs

4

5

18

6

16

15

14 − 7

Test Input

0 to −Vref

RFBA

3

VDD

17

OUTA

2

1

20

PASS / FAIL Output

1 k

Ω

VCC

DACB

DACA

8

Figure 8. Digitally-Programmable Window Comparator (Upper- and Lower-Limit Tester)

digitally-controlled signal attenuator

Figure 9 shows a TLC7528 configured as a two-channel programmable attenuator. Applications include stereo

audio and telephone signal level control. Table 3 shows input codes vs attenuation for a 0dB to 15.5dB range.

Output

A1

A2

VOB

VDD

TLC7528

DGND

AGND

REFB

DACA / DACB

WR

CS

DB0 − DB7

OUTA

RFBA

REFA

RFBB

OUTB

Data Bus

3

2

15

16

6

18

1

5

19

17

4

20

DACA

DACB

Attenuation dB = − 20 log10 D/256, D = digital input code

8

14 − 7

VIA

Figure 9. Digitally Controlled Dual Telephone Attenuator