AAT3128_08 Datasheet, PDF (8/12 Pages) Advanced Analogic Technologies – RGB LED Fashion Lighting Controller

ChargePump^TM
based on the current set level programmed by the R_SET
resistor. The second dimming 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 set-
tings based on an internal preset ROM table. The inter-
face 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 transi-
tions 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, mul-
tiple 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
PRODUCT DATASHEET
AAT3128
RGB LED Fashion Lighting Controller
timeout 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 possibility of losing synchroni-
zation between the AAT3128 and the system MCU.
Mood
M1
M2
M3
M4
Name
Rainbow 1
Electric Beat
Rainbow 2
Firelight
Color Description
Full color wheel control with continu-
ous 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.”
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.
EN/SET Timing
EN/SET
Code OFF
t_HI
t_LO
t_OFF
1
2
3
OFF
Figure 1: S²Cwire Timing Diagram.
8
www.analogictech.com
3128.2008.02.1.1