LTC1695

10

DEFINITIONS

divide the full-scale range. The resolution does not imply

linearity.

if all DAC bits are set to zeros. The LDO amplifier can have

a true negative offset, but due to the LTC1695’s single

transfer curve shown in Figure 1.

4.5V

70.3mV

4.430V

5.0V

78.1mV

4.922V

5.5V

85.9mV

5.414V

INL: Integral nonlinearity is the maximum deviation from

a straight line passing through the endpoints of the DAC

transfer curve. Due to the LTC1695’s single supply opera-

linearity is measured between full scale and the first code

(code 01) that guarantees a positive output. The INL error

at a given input code is calculated as follows:

measured at the given input code

DNL: Differential nonlinearity is the difference between the

measured change and the ideal 1LSB change between any

two adjacent codes. The DNL error between any two codes

is calculated as below:

DNL = (

between two adjacent codes

The

for the effect of negative offset in Figure 1. This is relevant

for code 1’s DNL.

The offset of the part is measured at the first code (code 1)

that produces an output voltage 0.5LSB greater than the

previous code.

ideal voltage difference between two successive codes.

Figure 1. Effect of Negative Offset

OUTPUT

VOLTAGE

DAC CODE

0V

NEGATIVE

OFFSET

1695 • F01