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AS1520/AS1521

4 Pinout

Pin Assignments

Figure 2. Pin Assignments (Top View)

Pin Descriptions

Table 1. Pin Descriptions

Pin Number

Pin Name

Description

1:8

CH0:CH7

Analog Sampling Inputs. These eight pins serve as analog sampling inputs.

9COM

Common Analog Inputs. Tie this pin to ground in single-ended mode.

10

Positive Supply Voltage

11

REF

Reference-Buffer Output/A/DC Reference Input. This pin serves as the reference

voltage for analog-to-digital conversions. In internal reference mode, the reference

buffer provides a +2.50V nominal output, externally adjustable at pin REFADJ. In

12

REFADJ

Reference-Buffer Amplifier Input. To disable the reference-buffer amplifier, tie this

13

GND

Analog and Digital Ground

14

DOUT

Serial Data Output. Data is clocked out at the rising edge of pin SCLK. DOUT is high

impedance when CSN is high.

15

SSTRB

Serial Strobe Output. SSTRB pulses high for one clock period before the MSB is

clocked out. SSTRB is high impedance when CSN is high.

16

DIN

Serial Data Input. Data is clocked in at the rising edge of SCLK.

17

CSN

Active-Low Chip Select. Data will not be clocked into pin DIN unless CSN is low.

When CSN is high, pins DOUT and SSTRB are high impedance.

18

SCLK

Serial Clock Input. This pin clocks data into and out of the serial interface, and is used

to set the conversion speed.

Note: The duty cycle must be between 40 and 60%.

19

Positive Supply Voltage

20

Positive Supply Voltage

AS1520/

AS1521

1

CH0

2

CH1

3

CH2

4

CH3

5

CH4

6

CH5

7

CH6

8

CH7

9

COM

10

18 SCLK

17 CSN

16 DIN

15 SSTRB

14 DOUT

13 GND

12 REFADJ

11 REF