www.ams.com/LED-Driver-ICs/AS1109

Revision 1.21

2 - 24

AS1109

Datasheet

4 Pin Assignments

Figure 2. Pin Assignments (Top View)

4.1 Pin Descriptions

Table 1. Pin Descriptions

Pin Number

Pin Name

Description

16-pin QSOP-150

16-pin SOIC-150

16-pin QFN

(4x4mm)

115

GND

Ground

216

SDI

Serial Data Input

31

CLK

Serial Data Clock. The rising edge of the CLK signal is used to clock data into and at

the falling edge out of the AS1109 shift register. In error mode, the rising edge of the CLK

signal is used to switch error modes.

42

LD

Serial Data Load. Data is transferred to the data register at the rising edge of this pin.

5:12

3:10

OUTN0:7

Output Current Drivers. These pins are used as LED drivers or for input sense for

diagnostic modes.

13

11

OEN

Output Enable. The active-low pin OEN signal can always enable output drivers to sink

current independent of the AS1109 mode.

0 = Output drivers are enabled.

1 = Output drivers are disabled.

14

12

SDO

Serial Data Output. In normal mode SDO is clocked out 8.5 clock cycles after SDI is

clocked in.

In global error detection mode this pin indicates the occurrence of a global error.

0 = Global error mode returned an error.

1 = No errors.

15

13

REXT

External Resistor Connection. This pin connects through the external resistor (REXT)

to GND, to setup the load current.

16

14

VDD

Positive Supply Voltage

1

GND

AS1109

16 VDD

2

SDI

3

CLK

4

LD

5

OUTN0

15 REXT

14 SDO

13 OEN

9 OUTN4

8

OUTN3

7

OUTN2

6

OUTN1

12 OUTN7

11 OUTN6

10 OUTN5

SDO

GND VDD

REXT

13

6

12

OUTN7

10

5

14

15

CLK

1

LD

2

OUTN1

4

AS1109

16-pin QFN

(4x4mm)

OUTN0

3

7

8

OUTN6

9

OEN

11

SDI

16

16-pin QSOP-150

16-pin SOIC-150