LTC1044A
12V CMOS
Voltage Converter
FEATURES
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s
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s
s
DESCRIPTIO
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s
1.5V to 12V Operating Supply Voltage Range
13V Absolute Maximum Rating
200µA Maximum No Load Supply Current at 5V
Boost Pin (Pin 1) for Higher Switching Frequency
97% Minimum Open Circuit Voltage Conversion
Efficiency
95% Minimum Power Conversion Efficiency
I
S
= 1.5µA with 5V Supply When OSC Pin = 0V or V
+
High Voltage Upgrade to ICL7660/LTC1044
The LTC1044A is a monolithic CMOS switched-capacitor
voltage converter. It plugs in for ICL7660/LTC1044 in
applications where higher input voltage (up to 12V) is
needed. The LTC1044A provides several conversion func-
tions without using inductors. The input voltage can be
inverted (V
OUT
= – V
IN
), doubled (V
OUT
= 2V
IN
), divided
(V
OUT
= V
IN
/2) or multiplied (V
OUT
=
±nV
IN
).
To optimize performance in specific applications, a boost
function is available to raise the internal oscillator fre-
quency by a factor of 7. Smaller external capacitors can be
used in higher frequency operation to save board space.
The internal oscillator can also be disabled to save power.
The supply current drops to 1.5µA at 5V input when the
OSC pin is tied to GND or V
+
.
APPLICATI
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Conversion of 10V to
±10V
Supplies
Conversion of 5V to
±5V
Supplies
Precise Voltage Division: V
OUT
= V
IN
/2
±20ppm
Voltage Multiplication: V
OUT
=
±nV
IN
Supply Splitter: V
OUT
=
±V
S
/2
Automotive Applications
Battery Systems with 9V Wall Adapters/Chargers
TYPICAL APPLICATI
Generating – 10V from 10V
LTC1044A
1
2
BOOST
CAP
+
GND
CAP
–
V
+
OSC
LV
V
OUT
LTC1044A • TA01
Output Voltage vs Load Current, V
+
= 10V
0
8
7
10V INPUT
OUTPUT VOLTAGE (V)
–1
–2
–3
–4
–5
–6
–7
–8
–9
–10
0
T
A
= 25°C
C1 = C2 = 10µF
+
10µF
3
4
6
5
–10V OUTPUT
10µF
10 20 30 40 50 60 70 80 90 100
LOAD CURRENT (mA)
LTC1044A • TA02
U
SLOPE = 45Ω
+
UO
UO
1
LINER [ LINEAR TECHNOLOGY ]
