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Dc electrical characteristics – Rainbow Electronics ADC1001 User Manual

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DC Electrical Characteristics

The following specifications apply for V

CC

e

5 V

DC

and T

MIN

s

T

A

s

T

MAX

unless otherwise specified

Symbol

Parameter

Conditions

MIn

Typ

Max

Units

CONTROL INPUTS

Note CLK IN is the input of a Schmitt trigger circuit and is therefore specified separately

V

IN

(1)

Logical ‘‘1’’ Input Voltage

V

CC

e

5 25 V

DC

2 0

15

V

DC

(Except CLK IN)

V

IN

(0)

Logical ‘‘0’’ Input Voltage

V

CC

e

4 75 V

DC

0 8

V

DC

(Except CLK IN)

I

IN

(1)

Logical ‘‘1’’ Input Current

V

IN

e

5 V

DC

0 005

1

m

A

DC

(All Inputs)

I

IN

(0)

Logical ‘‘0’’ input Current

V

IN

e

0 V

DC

b

1

b

0 005

m

A

DC

(All Inputs)

CLOCK IN

V

T

a

CLK IN Positive Going

2 7

3 1

3 5

V

DC

Threshold Voltage

V

T

b

CLK IN Negative Going

1 5

1 8

2 1

V

DC

Threshold Voltage

V

H

CLK IN Hysteresis

0 6

1 3

2 0

V

DC

(V

T

a

)b(V

T

b

)

OUTPUTS AND INTR

V

OUT

(0)

Logical ‘‘0’’ Output Voltage

I

OUT

e

1 6 mA V

CC

e

4 75 V

DC

0 4

V

DC

V

OUT

(1)

Logical ‘‘1’’ Output Voltage

I

O

e b

360 mA V

CC

e

4 75 V

DC

2 4

V

DC

I

O

e b

10 mA V

CC

e

4 75 V

DC

4 5

V

DC

I

OUT

TRI-STATE Disabled Output

V

OUT

e

0 4 V

DC

0 1

b

100

m

A

DC

Leakage (All Data Buffers)

V

OUT

e

5 V

DC

0 1

3

m

A

DC

I

SOURCE

V

OUT

Short to GND T

A

e

25 C

4 5

6

mA

DC

I

SINK

V

OUT

Short to V

CC

T

A

e

25 C

9 0

16

mA

DC

POWER SUPPLY

I

CC

Supply Current (Includes

f

CLK

e

410 kHz

Ladder Current)

V

REF

2eNC T

A

e

25 C

and CSe1

2 5

5 0

mA

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 conditions

Note 2

All voltages are measured with respect to GND unless otherwise specified The separate A GND point should always be wired to the D GND

Note 3

A zener diode exists internally from V

CC

to GND and has a typical breakdown voltage of 7 V

DC

Note 4

For V

IN

(

b

)

t

V

IN

(

a

) the digital output code will be all zeros Two on-chip diodes are tied to each analog input (see Block Diagram) which will forward

conduct for analog input voltages one diode drop below ground or one diode drop greater than the V

CC

supply Be careful during testing at low V

CC

levels (4 5V)

as high level analog inputs (5V) can cause this input diode to conduct

especially at elevated temperatures and cause errors for analog inputs near fullscale The

spec allows 50 mV forward bias of either diode This means that as long as the analog V

IN

does not exceed the supply voltage by more than 50 mV the output

code will be correct To achieve an absolute 0 V

DC

to 5 V

DC

input voltage range will therefore require a minimum supply voltage of 4 950 V

DC

over temperature

variations initial tolerance and loading

Note 5

With an asynchronous start pulse up to 8 clock periods may be required before the internal clock phases are proper to start the conversion process The

start request is internally latched see

Figure 1

Note 6

The CS input is assumed to bracket the WR strobe input and therefore timing is dependent on the WR pulse width An arbitrarily wide pulse width will hold

the converter in a reset mode and the start of conversion is initiated by the low to high transition of the WR pulse (see Timing Diagrams)

Note 7

All typical values are for T

A

e

25 C

Note 8

Accuracy is guaranteed at f

CLK

e

410 kHz At higher clock frequencies accuracy can degrade

Note 9

The V

REF 2

pin is the center point of a two resistor divider (each resistor is 2 4kX) connected from V

CC

to ground Total ladder input resistance is the sum

of these two equal resistors

Note 10

Human body model 100 pF discharged through a 1 5 kX resistor

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