www.austriamicrosystems.com/LED-Driver-ICs/AS1118

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AS1118

Datasheet - P i n o u t

4 Pinout

Pin Assignments

Figure 2. Pin Assignments (Top View)

Pin Descriptions

Table 2. Pin Descriptions

Pin Name

TQFN(4x4)-24

Description

SDI

22

Serial-Data Input. Data is loaded into the internal 16-bit shift register on the

rising edge of pin SCL.

DIG0:DIG7

1, 2, 4, 5, 7, 8, 23,

24

Digit Drive Lines. Eight digit drive lines that sink current from the display

cathode.

GND

3

Ground.

LD

9

Load. Serial Data is loaded into the shift register while this pin is low. The last

16 bits of serial data are latched on the rising edge of this pin.

RESETN

6

Reset Input. Pull this pin to low to resest all registers (set to default values) and

to put the device into shutdown.

10

set the peak segment current (see Selecting RSET Resistor Value and Using

External Drivers on page 15).

SCL

11

Serial-Clock Input. 10MHz maximum rate. Data is shifted into the internal shift

register on the rising edge of this pin. Data is clocked out of pin SDO on the

rising edge of this pin.

SEGA:SEGG,

SEGDP

12-15,

17-20

Seven Segment and Decimal Point Drive Lines. 8 seven-segment drives and

decimal point drive that source current to the display.

VDD

16

Positive Supply Voltage. Connect to +2.7V to +5.5V supply. Bypass this pin to

GND with a 10µF and a 0.1µF capacitor to avoid power supply ripple.

SDO

21

Serial-Data Output. The data into pin SDI is valid at pin SDO 16 clock cycles

later. This pin is used to daisy-chain several devices and is never high-

impedance.

Exposed Pad

Exposed Pad. This pin also functions as a heat sink. Solder it to a large pad or

to the circuit-board ground plane to maximize power dissipation.

SEG E

8

18

SEGB

14

DIG2

1

GND

3

AS1118

DIG5

5

10

12

VDD

16

SEGC

17

SEGG

15

SEGF

13

DIG3

2

DIG4

4

RESETN

6

11

9

7

23

21

19

20

22

24