18

®

DAC7644

2.5

2.0

1.5

1.0

0.5

0

–0.5

–1.0

–1.5

2.5

2.0

1.5

1.0

0.5

0

–0.5

–1.0

–1.5

LINEARITY ERROR AND

DIFFERENTIAL LINEARITY ERROR vs CODE

(DAC A, +25

°C)

0000

H

2000

H

4000

H

6000

H

8000

H

Digital Input Code

A000

H C000H

E000

H FFFFH

2.0

1.5

1.0

0.5

0

–0.5

–1.0

–1.5

–2.0

2.0

1.5

1.0

0.5

0

–0.5

–1.0

–1.5

–2.0

LINEARITY ERROR AND

DIFFERENTIAL LINEARITY ERROR vs CODE

(DAC A, +25

°C)

0000

H

2000

H

4000

H

6000

H

8000

H

Digital Input Code

A000

H C000H

E000

H FFFFH

+2.5V

+V

+1.25V

+V

NC

NC

NC

NC

V

OUTA Sense

V

OUTA

V

REFL AB Sense

V

REFL AB

V

REFH AB

V

REFH AB Sense

V

OUTB Sense

V

OUTB

48

47

46

45

44

43

42

41

40

39

38

37

DAC7644

1000pF

2200pF

+V

OPA2350

100

Ω

1000pF

2200pF

100

Ω

V

OUT

V

OUT

FIGURE 9. Single-Supply Buffered Reference with VREFL = +1.25V and VREFH = +2.5V (1/2 DAC7644).

FIGURE 7. Integral Linearity and Differential Linearity

Error Curves for Figure 6.

FIGURE 8. Integral Linearity and Differential Linearity

Error Curves for Figure 9.

FIGURE 10. Single-Supply Buffered VREFH (1/2 DAC7644).

NC

NC

NC

NC

V

OUTA Sense

V

OUTA

V

REFL AB Sense

V

REFL AB

V

REFH AB

V

REFH AB Sense

V

OUTB Sense

V

OUTB

48

47

46

45

44

43

42

41

40

39

38

37

DAC7644

+V

1000pF

100

Ω

+2.5V

OPA350

+V

V

OUT

V

OUT

2200pF