AAT3164 Datasheet, PDF (9/14 Pages) Advanced Analogic Technologies – High Efficiency 1X/1.5X/2X Charge Pump for Six-Channel White LED Applications

AAT3164
High Efficiency 1X/1.5X/2X Charge Pump for
Six-Channel White LED Applications
Data
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
All Outputs D1~D6
100%
84%
71%
60%
51%
43%
35%
30%
25%
21%
17%
14%
1.8mA
1mA
530µA
50µA
Table 1: Current Level Settings as a
Percentage of the Maximum Level Set by R_SET.
The built-in S²Cwire interface records rising edges of
the EN/SET pin and decodes them into these cur-
rent level settings. S²Cwire latches data after the
EN/SET pin has been held high for time T_LAT. A sep-
arate mode is available for ultra-low LED current
operation. This mode is enabled by setting Data 13
to 16. While the AAT3164 is operating in low current
and 1X mode, the total quiescent current is reduced
to typically 70µA. When EN/SET is held low for an
amount of time longer than T_OFF (500µs), the
AAT3164 enters shutdown mode and draws less
than 1µA from IN. Data register is reset to 0 during
shutdown.
Auto-Disable Feature
The AAT3164 is equipped with an auto-disable fea-
ture for each LED channel. After the IC is enabled,
a test current of 150µA (typical) is forced through
each sink channel. The LED must develop a for-
ward voltage of 0.8V for the channel to turn on.
This allows individual channels to be disabled by
connecting the respective sink pin to OUT. This
feature is convenient for disabling an unused chan-
nel or protecting against an LED fail short event.
Thermal Protection
The AAT3164 has a built-in thermal protection cir-
cuit that will shut down the charge pump if the die
temperature rises above the thermal limit, as is the
case during a short-circuit of the OUT pin.
EN/SET
Data Reg
T _HI
T_LO
T_LAT
1
2
n - 1 n ≤ 16
1
T_OFF
n
0
Figure 1: S²Cwire Serial Interface Timing Diagram.
3164.2006.07.1.0
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