AAT1230/1230-1
18V 100mA Step-Up Converter
Option 3: Dynamic Voltage Control Using
S2Cwire Interface
abled, the register is reset to the default value, which
sets the FB2 pin to 0.6V if EN is subsequently pulled
high.
The output can be dynamically adjusted by the host
controller to any of 16 pre-set output voltage levels
using the integrated S2Cwire interface. The
EN/SET pin serves as the S2Cwire interface input.
The SEL pin must be pulled low when using the
S2Cwire interface.
S2Cwire Output Voltage Programming
The AAT1230/1230-1 is programmed through the
S2Cwire interface according to Table 2. The rising
clock edges received through the EN/SET pin
determine the feedback reference and output volt-
age set-point. Upon power up with the SEL pin
low and prior to S2Cwire programming, the default
feedback reference voltage is set to 0.6V.
S2Cwire Serial Interface
AnalogicTech's S2Cwire serial interface is a propri-
etary high-speed single-wire interface available
only from AnalogicTech. The S2Cwire interface
records rising edges of the EN/SET input and
decodes into 16 different states. Each state corre-
sponds to a voltage setting on the FB2 pin, as
shown in Table 2.
EN/SET
Rising
Edges
FB2
Reference
Voltage (V)
EN/SET
FB2
Rising Reference
Edges Voltage (V)
1
2
3
4
5
6
7
8
0.60 (Default)
0.64
9
0.92
0.96
1.00
1.04
1.08
1.12
1.16
1.20
10
11
12
13
14
15
16
0.68
S2Cwire Serial Interface Timing
0.72
The S2Cwire serial interface has flexible timing.
Data can be clocked-in at speeds up to 1MHz. After
data has been submitted, EN/SET is held high to
latch the data for a period TLAT. The output is sub-
sequently changed to the predetermined voltage.
When EN/SET is set low for a time greater than
TOFF, the AAT1230/1230-1 is disabled. When dis-
0.76
0.80
0.84
0.88
Table 2: S2Cwire Voltage Control Settings
(SEL = Low).
THI
TOFF
TLO
TLAT
EN/SET
1
2
n-1
n ≤ 16
0
n-1
Data Reg
0
Figure 2: S2Cwire Timing Diagram to Program the Output Voltage.
14
1230.2006.10.1.4
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
