AS1116 DB-RED austriamicrosystems, AS1116 DB-RED Datasheet - Page 15

• Manufacturer Part Number: AS1116 DB-RED
• Description: BOARD DEMO AS1116 RED
• Manufacturer: austriamicrosystems

Specifications of AS1116 DB-RED

• Current - Output / Channel: *
• Outputs And Type: 8, Non-Isolated
• Voltage - Output: *
• Features: 64 LED Driver with Error Detection, SPI
• Voltage - Input: 2.7 ~ 5.5 V
• Utilized Ic / Part: AS1116
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption

AS1116
Datasheet - Ty p i c a l A p p l i c a t i o n
9 Typical Application
Selecting R
Brightness of the display segments is controlled via R
current that flows through the LEDs.
Segment current is about 200 times the current in I
ing voltages, and LED voltage drop (V
drive is 47mA. If higher currents are needed, external drivers must be used, in which case it is no longer necessary
that the devices drive high currents.
Note: The display brightness can also be logically controlled
Table 21. R
Table 22. R
Calculating Power Dissipation
The upper limit for power dissipation (PD) for the AS1116 is determined from the following equation:
Where:
V
DUTY is the duty cycle set by intensity register
N is the number of segments driven (worst case is 8)
V
I
Dissipation Example:
Thus, for a QSOP-24 package
In this example the maximum ambient temperature must stay below 73.88°C.
www.austriamicrosystems.com/LED-Driver-ICs/AS1116
SEG
(mA)
I
I
DD
LED
SEG
SEG
40
30
20
10
is the supply voltage.
= segment current set by RSET
40
30
20
10
is the LED forward voltage
(mA)
36.89k Ω 35.7k Ω
17.7k Ω
11.6k Ω
8.6k Ω
SET
SET
1.5V
vs. Segment Current and LED Forward Voltage, V
vs. Segment Current and LED Forward Voltage, V
SET
10.7k Ω
22.2k Ω
6.9k Ω
1.5V
5k Ω
Resistor Value and Using External Drivers
17.3k Ω
11.2k Ω
I
8.3k Ω
SEG
2.0V
T
V
J,MAX
LED
= 40mA, N = 8, DUTY = 15/16, V
PD = 5V(5mA) + (5V - 2.2V)(15/16 x 40mA x 8) = 0.865W
20.7k Ω
4.4k Ω
5.9k Ω
9.6k Ω
PD = (V
2.0V
Θ
= T
10.8k Ω
16.6k Ω 15.6k Ω 13.6k Ω
34.5k Ω 32.5k Ω 29.1k Ω
V
7.9k Ω
2.5V
LED
JA
AMB
= +88°C/W, the maximum allowed T
DD
LED
+ PD x
x 5mA) + (V
7.6k Ω
9.9k Ω
) are given in
3.0V
13.9k Ω
28.8k Ω
6.7k Ω
9.1k Ω
1.5V
Θ
(page
JA
5.2k Ω
7.8k Ω
= 150°C = T
SET
3.5V
DD
SET
13).
. Typical values for R
13.3k Ω
27.7k Ω
6.4k Ω
8.8k Ω
Table 21
Revision 1.05
V
2.0V
- V
LED
. The current that flows between V
LED
LED
11.35k Ω 11.12k Ω 10.84k Ω 10.49k Ω 10.2k Ω 9.9k Ω
)(DUTY x I
(see Intensity Control Register (0x0A) on page
15.4k Ω
23.6k Ω
48.9k Ω
AMB
= 2.2V at 40mA, V
1.5V
&
12.6k Ω
5.7k Ω
8.1k Ω
26k Ω
DD
DD
Table
2.5V
+ 0.865W x 88°C/W
= 2.7V & 3.3V & 3.6V
= 4.0V & 5.0V
AMB
15.1k Ω
23.1k Ω
47.8k Ω
22. The maximum current the AS1116 can
SEG
2.0V
SET
is given by:
x N)
10.18k Ω
15.6k Ω
31.9k Ω
for different segment currents, operat-
7.5k Ω
1.5V
DD
14.7k Ω
22.6k Ω
46.9k Ω
2.5V
= 5V
V
LED
7.2k Ω
9.8k Ω
15k Ω
31k Ω
2.0V
DD
14.4k Ω 13.6k Ω 13.1k Ω
45.4k Ω 43.8k Ω 42k Ω
22k Ω
3.0V
and I
V
LED
SET
14.3k Ω
29.5k Ω
6.6k Ω
9.2k Ω
21.1k Ω 20.2k Ω
2.5V
3.5V
defines the
12).
27.3k Ω
5.5k Ω
7.5k Ω
13k Ω
(EQ 1)
(EQ 2)
(EQ 3)
(EQ 4)
3.0V
4.0V
15 - 20