AAT3128 Datasheet, PDF (8/13 Pages) Advanced Analogic Technologies – RGB LED Fashion Lighting Controller

AAT3128
RGB LED Fashion Lighting Controller
selects a preset group of 64 unique colors that the
system controller repeatedly sequences through at
a selected fast or slow rate.
RGB LED brightness and color change timing may
be varied by a choice of two levels for both. The
Brightness control permits the full current to power
the RGB LED based on the current set level pro-
grammed by the R_SET resistor. The second dim-
ming level is fixed at 6dB below that programmed
by the R_SET resistor. The pace of the color change
for a given mood light option can be set to a fast or
slow rate.
Through the S²Cwire interface, mood options allow
the user to select between four different moods,
each with two brightness levels and two speeds,
based on the number of rising edges of the
EN/SET pin. 16 unique moods are selected based
on the settings in Table 2.
EN/SET Serial Interface
The lighting mood output is controlled by the
EN/SET pin, using AnalogicTech’s Simple Serial
Control™ (S²Cwire) interface. The interface records
rising edges of the EN/SET pin, and decodes them
into 16 individual settings based on an internal pre-
set ROM table. The interface counter can be
clocked at speeds up to 1MHz. The rising edges of
EN/SET input enable the IC and are counted for 1
to 16 edges based on the desired mode. Once the
final clock cycle is input for the desired mode the
EN/SET pin is held high to enable the device output.
The device is disabled 500µs after the EN/SET pin
transitions to a logic low state.
The EN/SET timing is designed to accommodate a
wide range of data rates. After the first rising edge of
EN/SET, the charge pump is enabled and reaches
full capacity after the soft-start time (T_SS). During the
soft start time, multiple clock pulses may be entered
on the EN/SET pin to set the final output current level
with a single burst of clocks. A constant current is
sourced and the programmed color mood is enabled
as long as EN/SET remains in a logic high state. The
current source outputs are switched off after EN/SET
has remained in a low state for at least the T_OFF time-
out period. After the T_OFF time out time, all internal
registers are reset and the charge pump is disabled.
It is advisable to issue a 500µs low pulse to reset
the data registers before send new sets of data to
change lighting modes. This will avoid any possi-
bility of losing synchronization between the
AAT3128 and the system MCU.
Mood Name
M1 Rainbow 1
M2 Electric Beat
M3 Rainbow 2
M4
Firelight
Color Description
Full color wheel control
with continuous smooth
transitions
Pulsing Blue – White –
Red color tones
Full color wheel control
with varied timing for
transitions
Red-Orange-Yellow
flickering light
Table 1: Programmable RGB LED Color
Lighting “Moods.”
8
Data
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Bright/Dim
B
B
B
B
B
B
B
B
D
D
D
D
D
D
D
D
Fast/Slow
F
F
F
F
S
S
S
S
F
F
F
F
S
S
S
S
Mood
M1
M2
M3
M4
M1
M2
M3
M4
M1
M2
M3
M4
M1
M2
M3
M4
Table 2: AAT3128 S²Cwire Programming Modes.
3128.2007.09.1.0