AS1108
Datasheet - P i n o u t
4 Pinout
Pin Assignments
Figure 2. Pin Assignments (Top View)
DOUT 1
DIN 2
DIG 0 3
GND 4
DIG 2 5
DIG 3 6
GND 7
DIG 1 8
LOAD/CSN 9
CLK 10
20 SEG D
19 SEG DP
18 SEG E
17 SEG C
AS1108
16 VDD
15 ISET
14 SEG G
13 SEG B
12 SEG F
11 SEG A
Pin Descriptions
Pin Number
1
Table 1. Pin Descriptions
3, 5, 6, 8
4, 7
11, 12, 13, 14,
17, 18, 19, 20
15
Te
c
hn
ic a
al m
co s
A
nt G
en
ts
til
Pin Name
DOUT
DIN
2
DIG 0:DIG 3
GND
9
LOAD/CSN
10
CLK
SEG A:SEG G,
SEG DP
ISET
VDD
16
Revision 2.13
Description
Serial-Data Output.
The data into pin DIN is valid at pin DOUT 16.5 clock
cycles later. This pin is used to daisy-chain several AS1108 devices and is
never high-impedance.
Serial-Data Input.
Data is loaded into the internal 16-bit shift register on the
rising edge of pin CLK.
Digit Drive Lines.
4 four-digit drive lines that sink current from the display
common cathode. The AS1108 pulls the digit outputs to V
DD
when turned off.
Ground.
Both GND pins must be connected.
Load-Data Input.
The last 16 bits of serial data are latched on the rising edge
of this pin.
Chip-Select Input
(AS1108 SPI-enabled only). 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.
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 DOUT on the
falling edge of this pin. On the AS1108 SPI-enabled, the CLK input is active
only while pin LOAD/CSN is low.
Seven Segment and Decimal Point Drive Lines.
8 seven-segment drives
and decimal point drive that source current to the display. When a segment
driver is turned off it is pulled to GND.
Set Segment Current.
Connect to V
DD
through R
SET
to set the peak segment
current (see Selecting RSET Resistor Value and Using External Drivers on
Positive Supply Voltage.
Connect to +2.7 to +5.5V supply.
lv
2 - 20
al
id
AMSCO [ AUSTRIAMICROSYSTEMS AG ]
