TLV5580

8BIT, 80 MSPS LOW POWER A/D CONVERTER

SLAS205B − DECEMBER 1998 − REVISED OCTOBER 2003

www.ti.com

7

ELECTRICAL CHARACTERISTICS OVER RECOMMENDED OPERATING CONDITIONS WITH FCLK = 80

MSPS AND USE OF EXTERNAL VOLTAGE REFERENCES (unless otherwise noted)

DC ACCURACY

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Integral nonlinearity (INL), best-fit

Internal references (see Note 1)

TA = −40°C to 85°C

−2.4

±1

2.4

LSB

Integral nonlinearity (INL), best-fit

Internal references (see Note 1)

TA = −40°C to 85°C

−2.4

±1

2.4

LSB

Differential nonlinearity (DNL)

Internal references (see Note 2)

TA = −40°C to 85°C

−1

±0.6

1.3

LSB

Zero error

AVDD = DVDD = 3.3 V, DRVDD = 3 V

See Note 3

5

%FS

Full scale error

AVDD = DVDD = 3.3 V, DRVDD = 3 V

See Note 3

5

%FS

1. Integral nonlinearity refers to the deviation of each individual code from a line drawn from zero to full scale. The point used as zero

occurs 1/2 LSB before the first code transition. The full−scale point is defined as a level 1/2 LSB beyond the last code transition. The deviation

is measured from the center of each particular code to the true straight line between these two endpoints.

2. An ideal ADC exhibits code transitions that are exactly 1 LSB apart. DNL is the deviation from this ideal value. Therefore this measure indicates

how uniform the transfer function step sizes are. The ideal step size is defined here as the step size for the device under test (i.e., (last transition

level − first transition level)

÷ (2n − 2)). Using this definition for DNL separates the effects of gain and offset error. A minimum DNL better than −1

LSB ensures no missing codes.

3. Zero error is defined as the difference in analog input voltage − between the ideal voltage and the actual voltage − that will switch the ADC output

from code 0 to code 1. The ideal voltage level is determined by adding the voltage corresponding to 1/2 LSB to the bottom reference level. The

voltage corresponding to 1 LSB is found from the difference of top and bottom references divided by the number of ADC output levels (256).

Full-scale error is defined as the difference in analog input voltage – between the ideal voltage and the actual voltage – that will switch the ADC

output from code 254 to code 255. The ideal voltage level is determined by subtracting the voltage corresponding to 1.5 LSB from the top reference

level. The voltage corresponding to 1 LSB is found from the difference of top and bottom references divided by the number of ADC output levels

(256).

ANALOG INPUT

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

CI

Input capacitance

4

pF

REFERENCE INPUT (AVDD = DVDD = DRVDD = 3.6 V)

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Rref

Reference input resistance

200

Ω

Iref

Reference input current

5

mA

REFERENCE OUTPUTS

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

V(REFTO)

Reference top offset voltage

Absolute min/max values valid

2.07

2 + [(AVDD − 3) ÷ 2]

2.21

V

V(REFBO)

Reference bottom offset voltage

Absolute min/max values valid

and tested for AVDD = 3.3 V

1.09

1 + [(AVDD − 3) ÷ 2]

1.21

V