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ADS820

4

SBAS037B

PIN

DESIGNATOR

DESCRIPTION

1

GND

Ground

2

B1

Bit 1, Most Significant Bit (MSB)

3

B2

Bit 2

4

B3

Bit 3

5

B4

Bit 4

6

B5

Bit 5

7

B6

Bit 6

8

B7

Bit 7

9

B8

Bit 8

10

B9

Bit 9

11

B10

Bit 10, Least Significant Bit (LSB)

12

DNC

Do not connect.

13

DNC

Do not connect.

14

GND

Ground

15

+VS

+5V Power Supply

16

CLK

Convert Clock Input, 50% Duty Cycle

17

+VS

+5V Power Supply

18

OE

HIGH: High Impedance State. LOW or Floating:

Normal Operation. Internal pull-down resistor.

19

MSBI

Most Significant Bit Inversion, HIGH: MSB in-

verted for complementary output. LOW or Float-

ing: Straight output. Internal pull-down resistor.

20

+VS

+5V Power Supply

21

REFB

Bottom Reference Bypass. For external bypass-

ing of internal +1.25V reference.

22

CM

Common-Mode Voltage. It is derived by (REFT +

REFB)/2.

23

REFT

Top Reference Bypass. For external bypassing

of internal +3.25V reference.

24

+VS

+5V Power Supply

25

GND

Ground

26

IN

Input

27

IN

Complementary Input

28

GND

Ground

PIN DESCRIPTIONS

PIN CONFIGURATION

Top View

SO

GND

Bit 1(MSB)

Bit 2

Bit 3

Bit 4

Bit 5

Bit 6

Bit 7

Bit 8

Bit 9

Bit 10 (LSB)

DNC

DNC

GND

GND

IN

IN

GND

+V

S

REFT

CM

REFB

+V

S

MSBI

OE

+V

S

CLK

+V

S

1

2

3

4

5

6

7

8

9

10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

15

ADS820

DNC: Do Not Connect

TIMING DIAGRAM

SYMBOL

DESCRIPTION

MIN

TYP

MAX

UNITS

tCONV

Convert Clock Period

50

100

µsns

tL

Clock Pulse LOW

24

25

ns

tH

Clock Pulse HIGH

24

25

ns

tD

Aperture Delay

2

ns

t1

Data Hold Time, CL = 0pF

3.9

ns

t2

New Data Delay Time, CL = 15pF max

12.5

ns

Track

Hold

"N"

Hold

"N + 1"

Hold

"N + 2"

Hold

"N + 3"

Hold

"N + 4"

Hold

"N + 5"

Hold

"N + 6"

Track

Data Valid

N – 7

Data Valid

N – 6

Internal

Track-and-Hold

Convert

Clock

Output

Data

t

D

t

2

t

1

Data Latency

(6.5 Clock Cycles)

t

CONV

t

L

t

H

Track

Track

Track

Track

N – 3

N – 5N – 4N – 2N – 1

N

Track

Track

Data Valid

N – 8

(1)

Data Invalid

NOTE: (1) “

” indicates the portion of the waveform that will stretch out at slower sample rates.