www.ams.com/LED-Driver-ICs/AS1105

Revision 1.36

2 - 15

AS1105

Datasheet - Pin Assignm ents

4 Pin Assignments

Figure 2. Pin Configuration (Top View)

4.1 Pin Descriptions

Table 1. Pin Descriptions

Pin Number

Pin Name

Description

1

DOUT

Serial data output for cascading drivers. The output is valid after 16.5 clock cycles. The output is

never set to high impedance.

2

DIN

Data input. Data is programmed into the 16-bit shift register on the rising CLK edge.

3,8,5,6

DIG0 : DIG3

4-digit driver lines that sink the current from the common cathode of the display. In shutdown mode

the AS1105 switches the outputs to VDD.

4,7

GND

Both GND pins must be connected.

9

LOAD

Strobe input. With the rising edge of the LOAD signal the 16-bit of serial data is latched into the

register.

10

CLK

Clock input. The interface is capable to support clock frequencies up to 10MHz. The serial data is

clocked into the internal shift register with the rising edge of the CLK signal. On the DOUT pin the

data is applied with the falling edge of CLK.

11:14, 17:20

SEGA:G, DP

Seven segment driver lines including the decimal point. When a segment is turned off the

output is connected to GND.

15

ISET

The current into ISET determines the peak current through the segments and therefore the

brightness.

16

VDD

Positive Supply Voltage (+5V)

AS1105

10

1

2

11

3

4

5

6

7

8

9

20

19

18

17

16

15

14

13

12

DOUT

DIN

DIG0

GND

DIG2

DIG3

GND

DIG1

LOAD

CLK

SEG D

SEG DP

SEG E

SEG C

VDD

ISET

SEG G

SEG B

SEG F

SEG A

SO