Dc electrical characteristics, Bandgap reference electrical characteristics – Rainbow Electronics ADC08161 User Manual

Page 5

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DC Electrical Characteristics

(Continued)

The following specifications apply for V

+

= 5V unless otherwise specified. Boldface limits apply for T

A

= T

J

= T

MIN

to T

MAX

;

all other limits T

A

= T

J

= 25˚C.

Symbol

Parameter

Conditions

ADC08161BIN, ADC08161CIN,

Units

(Limit)

ADC08161BIWM, ADC08161CIWM

Typical

Limit

(Note 7)

(Note 8)

I

SINK

Output Sink Current

V

OUT

= 5V

24

7

mA (min)

DB0–DB7, OFL , INT , RDY

I

C

Supply Current

CS = WR = RD = 0

11.5

20

mA (max)

C

OUT

Logic Output Capacitance

5

pF

C

IN

Logic Input Capacitance

5

pF

Bandgap Reference Electrical Characteristics

The following specifications apply for V

+

= 5V unless otherwise specified. Boldface limits apply for T

MIN

to T

MAX

; all other

limits T

A

= T

J

= 25˚C.

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 7)

(Note 8)

(Limit)

V

REFOUT

Internal Reference Output Voltage

“B” Grade

2.5

2.5

±

1.5%

V (max)

“C” Grade

2.5

±

2.0%

V

REF

/

T

Internal Reference Temperature

40

ppm/˚C

Coefficient

V

REF

/

I

L

Internal Reference Load

Sourcing (0

I

L

+10 mA)

0.01

0.1

%/mA (max)

Regulation

Line Regulation

4.75V

V

+

5.25V

0.5

6.0

mV (max)

I

SC

Short Circuit Current

V

REV

= 0V

35

mA (max)

V

REF

/

t

Long Term Stability

200

ppm/kHr

Start-Up Time

V

+

: 0V

5V, C

L

= 220 µF

40

ms

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not apply when operating
the device beyond its specified operating ratings. Operating Ratings indicate conditions for which the device is functional, but do not guarantee performance limits.
For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed specifications apply only for the test conditions listed. Some per-
formance characteristics may degrade when the device is not operated under the listed test conditions.

Note 2: All voltages are measured with respect to the GND pin, unless otherwise specified.

Note 3: When the input voltage (V

IN

) at any pin exceeds the power supply voltage (V

IN

<

GND or V

IN

>

V

+

), the absolute value of the current at that pin should be

limited to 5 mA or less. The 20 mA package input current specification limits the number of pins that can exceed the power supply boundaries with a 5 mA current
limit to four.

Note 4: The power dissipation of this device under normal operation should never exceed 875 mW (Quiescent Power Dissipation + TTL Loads on the digital outputs).
Caution should be taken not to exceed absolute maximum power rating when the device is operating in a severe fault condition (e.g., when any input or output ex-
ceeds the power supply). The maximum power dissipation must be derated at elevated temperatures and is dictated by T

JMAX

(maximum junction temperature),

θ

JA

(package junction to ambient thermal resistance), and T

A

(ambient temperature). The maximum allowable power dissipation at any temperature is PD

max

= (T

JMAX

− T

A

)/

θ

JA

or the number given in the Absolute Maximum Ratings, whichever is lower. The table below details T

JMAX

and

θ

JA

for the various packages and versions

of the ADC08161.

Part Number

T

JMAX

θ

JA

ADC08161B/CIN

105

51

ADC08161B/CIWM

105

85

Note 5: See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of soldering surface mount devices.

Note 6: Human body model, 100 pF discharged through a 1.5 k

resistor.

Note 7: Typicals are at 25˚C and represent most likely parametric norm.

Note 8: Limits are guaranteed to National’s AOQL (Average Output Quality Level).

Note 9: Total unadjusted error includes offset, full-scale, and linearity errors.

Note 10: Two on-chip diodes are tied to each analog input and are reversed biased during normal operation. One is connected to V

+

and the other is connected to

GND. They will become forward biased and conduct when an analog input voltage is equal to or greater than one diode drop above V

+

or below GND. Therefore,

caution should be exercised when testing with V

+

= 4.5V. Analog inputs with magnitudes equal to 5V can cause an input diode to conduct, especially at elevated tem-

peratures. This can create conversion errors for analog signals near full-scale. The specification allows 50 mV forward bias on either diode; e.g., the output code will
be correct as long as the analog input signal does not exceed the supply voltage by more than 50 mV. Exceeding this range on an unselected channel will corrupt
the reading of a selected channel. An absolute analog input signal voltage range of 0V

V

IN

5V can be achieved by ensuring that the minimum supply voltage ap-

plied to V

+

is 4.950V over temperature variations, initial tolerance, and loading.

5

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