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Pin descriptions and equivalent circuits – Rainbow Electronics ADC10080 User Manual

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Pin Descriptions and Equivalent Circuits

Pin No.

Symbol

Equivalent Circuit

Description

ANALOG I/O

12

V

IN−

Inverting analog input signal. With a 1.2V reference the

full-scale input signal level is 1.0 V

P-P

. This pin may be tied to

V

COM

(pin 4) for single-ended operation.

13

V

IN+

Non-inverting analog input signal. With a 1.2V reference the

full-scale input signal level is 1.0 V

P-P

.

6

V

REF

Reference input. This pin should be bypassed to V

SSA

with a

0.1 µF monolithic capacitor. V

REF

is 1.20V nominal. This pin

may be driven by a 1.20V external reference if desired. Do

not load this pin.

7

V

REFT

V

REFT

and V

REFB

are high impedance reference bypass pins

only. Connect a 0.1 µF capacitor from each of these pins to

V

SSA

. These pins should not be loaded. V

COM

should also be

bypassed with a 0.1 µF capacitor to V

SSA

. V

COM

may be used

to set the input common voltage V

CM

.

4

V

COM

8

V

REFB

DIGITAL I/O

1

CLK

Digital clock input. The range of frequencies for this input is

20 MHz to 80 MHz. The input is sampled on the rising edge

of this input.

15

DF

DF = “1” Two’s Complement

DF = “0” Offset Binary

28

STBY

This is the standby pin. When high, this pin sets the converter

into standby mode. When this pin is low, the converter is in

active mode.

5

IRS (Input Range

Select)

IRS = “V

DDA

” 2.0 V

P-P

input range

IRS = “V

SSA

” 1.5 V

P-P

input range

IRS = “Floating” 1.0 V

P-P

input range

If using both V

IN

+ and V

IN

- pins, (or differential mode), then

the peak-to-peak voltage refers to the differential voltage

(V

IN

+ - V

IN

-).

ADC10080

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