10-1038

Thermal Drift

larger of the two values is given as a specification represent-

ing worst case drift.

Gain Drift, Offset Drift, Reference Drift and Total Bipolar Drift

NOTE: FSR = Full Scale Output Voltage - Zero Scale Output

Voltage

Total Bipolar Drift is the variation of output voltage with

temperature, in the bipolar mode of operation. It represents

the net effect of drift in Gain, Offset, Linearity and Reference

Voltage. Total Bipolar Drift values are calculated, based on

measurements as explained above. Gain and Offset need

TBD apply for any input code and for any power supply set-

ting within the specified operating range.

Accuracy

Linearity Error (Short for “Integral Linearity Error.” Also,

sometimes called “Integral Nonlinearity” and “Nonlinearity”.)

The maximum deviation of the actual transfer characteristic

from an ideal straight line. The ideal line is positioned

according to end-point linearity for D/A converter products

from Intersil Corporation , i.e., the line is drawn between the

end-points of the actual transfer characteristic (codes 00...0

and 11...1).

Differential Linearity Error The difference between one

LSB and the output voltage change corresponding to any

two consecutive codes. A Differential Nonlinearity of

±1 LSB

or less guarantees monotonicity.

Monotonicity The property of a D/A converter’s transfer

function which guarantees that the output derivative will not

change sign in response to a sequence of increasing (or

decreasing) input codes. That is, the only output response to

a code change is to remain constant, increase for Increasing

code, or decrease for decreasing code.

Total Error The net output error resulting from all internal

effects (primarily non-ideal Gain, Offset, Linearity and

Reference Voltage). Supply voltages may be set to any

values within the specified operating range. Gain and offset

limits for Total Error apply for any input code and for any

temperature within the specified operating range.

Power Supply Sensitivity

Power Supply Sensitivity is a measure of the change in gain

and offset of the D/A converter resulting from a change in

expressed as full scale range percent of change divided by

power supply percent change.

Glitch

A glitch on the output of a D/A converter is a transient spike

resulting from unequal internal ON-OFF switching times.

Worst case glitches usually occur at half-scale, i.e., the

major carry code transition from 011...1 to 100...0 or vice

versa. For example, if turn ON is greater than OFF for

011...1 to 100...0, an intermediate state of 000...0 exists,

such that, the output momentarily glitches toward zero out-

put. Matched switching times and fast switching will reduce

glitches considerably. (Measured as one half the Product of

duration and amplitude.)

Decoupling and Grounding

For best accuracy and high frequency performance, the

grounding and decoupling scheme shown in Figure 1 should

be used. Decoupling capacitors should be connected close

to the HI-DAC80V/HI-DAC85V (preferably to the device pins)

and should be tantalum or electrolytic bypassed with

ceramic types for best high frequency noise rejection.

GainDrift

∆FSR ∆°C

⁄

FSR

--------------------------------

10

6

×

=

OffsetDrift

∆Offset ∆°C

⁄

FSR

-------------------------------------

10

6

×

=

ReferenceDrift

∆V

REF

∆°C

()

⁄

V

REF

---------------------------------------

×

=

To talBipolarDrift

∆V

O

∆°C

()

⁄

FSR

--------------------------------

10

6

×

=

PSS

∆FullScaleRange 100

×

FSR Nominal

()

-------------------------------------------------------------------

∆V

S

100

×

V

----------------------------------

-------------------------------------------------------------------

=

18

19

20

15

-

+

0.01

µF

1

µF

14

21

22

0.01

µF

1

µF

24

16

FIGURE 1.

HI-DAC80V, HI-DAC85V