LTC1044A
12V CMOS
Voltage Converter
FeaTures
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DescripTion
The
LTC
®
1044A
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 frequency
by a factor of seven. 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
+
.
L,
LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
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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
applicaTions
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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 applicaTion
Generating –10V from 10V
LTC1044A
1
BOOST
CAP
+
+
Output Voltage vs Load Current, V
+
= 10V
0
–1
–2
OUTPUT VOLTAGE (V)
–3
–4
–5
–6
–7
–8
–9
–10
0
10 20 30 40 50 60 70 80 90 100
LOAD CURRENT (mA)
1044a TA01b
V
8
7
6
5
10V INPUT
T
A
= 25°C
C1 = C2 = 10µF
+
2
10µF
3
4
OSC
LV
V
OUT
1044a TA01a
GND
CAP
–
–10V OUTPUT
10µF
+
SLOPE = 45
1044afa
For more information
www.linear.com/LTC1044A
1
LTC1044A
absoluTe MaxiMuM raTings
(Note 1)
Supply Voltage ..........................................................13V
Input Voltage on Pins 1, 6 and 7
(Note 2) ..................................–0.3V < V
IN
< V
+
+ 0.3V
Current into Pin 6....................................................20µA
Output Short-Circuit Duration
V
+
≤ 6.5V ......................................................Continuous
Operating Temperature Range
LTC1044AC .............................................. 0°C to 70°C
LTC1044AI ........................................... –40°C to 85°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec) .................. 300°C
pin conFiguraTion
TOP VIEW
BOOST 1
CAP
+
2
GND 3
CAP
–
TOP VIEW
8
7
6
5
V
+
OSC
LV
V
OUT
BOOST 1
CAP
+
2
GND 3
CAP
–
4
8
7
6
5
V
+
OSC
LV
V
OUT
4
N8 PACKAGE
8-LEAD PLASTIC DIP
T
JMAX
= 110°C,
θ
JA
= 100°C/W
S8 PACKAGE
8-LEAD PLASTIC SO
T
JMAX
= 110°C,
θ
JA
= 130°C/W
Consult factory for military grade parts
orDer inForMaTion
LEAD FREE FINISH
LTC1044ACN8#PBF
LTC1044AIN8#PBF
LTC1044ACS8#PBF
LTC1044AIS8#PBF
TAPE AND REEL
LTC1044ACN8#TRPBF
LTC1044AIN8#TRPBF
LTC1044ACS8#TRPBF
LTC1044AIS8#TRPBF
PART MARKING
LTC1044 ACN8
LTC1044 AIN8
1044A
1044AI
PACKAGE DESCRIPTION
8-Lead Plastic DIP
8-Lead Plastic DIP
8-Lead Plastic SO
8-Lead Plastic SO
TEMPERATURE RANGE
0°C to 70°C
–40°C to 85°C
0°C to 70°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on nonstandard lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
1044afa
2
For more information
www.linear.com/LTC1044A
LTC1044A
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
+
= 5V, C
OSC
= 0pF, unless otherwise noted.
LTC1044AC
SYMBOL PARAMETER
I
S
Supply Current
CONDITIONS
R
L
= ∞, Pins 1 and 7, No Connection
R
L
= ∞, Pins 1 and 7, No Connection,
V
+
= 3V
R
L
= 10k
R
L
= 10k
I
L
= 20mA, f
OSC
= 5kHz
V
+
= 2V, I
L
= 3mA, f
OSC
= 1kHz
f
OSC
P
EFF
Oscillator Frequency
Power Efficiency
Oscillator Sink or Source
Current
V
+
= 5V, (Note 3)
V
+
= 2V
RL = 5k, f
OSC
= 5kHz
V
OSC
= 0V or V
+
Pin 1 (BOOST) = 0V
Pin 1 (BOOST) = V
+
l
l
l
l
l
l
elecTrical characTerisTics
LTC1044AI
MAX
200
MIN
TYP
60
15
1.5
12
100
120
310
12
100
130
325
5
1
MAX
200
UNITS
μA
μA
V
V
Ω
Ω
Ω
kHz
kHz
98
99.9
3
20
%
%
µA
µA
MIN
TYP
60
15
Minimum Supply Voltage
Maximum Supply Voltage
R
OUT
Output Resistance
1.5
5
1
95
97
98
99.9
3
20
95
97
Voltage Conversion Efficiency RL = ∞
l
l
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
Connecting any input terminal to voltages greater than V
+
or less
than ground may cause destructive latchup. It is recommended that no
inputs from sources operating from external supplies be applied prior to
power-up of the LTC1044A.
Note 3:
f
OSC
is tested with C
OSC
= 100pF to minimize the effects of test
fixture capacitance loading. The 0pF frequency is correlated to this 100pF
test point, and is intended to simulate the capacitance at pin 7 when the
device is plugged into a test socket and no external capacitor is used.
1044afa
For more information
www.linear.com/LTC1044A
3
LTC1044A
Typical perForMance characTerisTics
Operating Voltage Range vs
Temperature
14
12
POWER EFFICIENCY (%)
SUPPLY VOLTAGE (V)
10
8
6
4
2
0
–55 –25
100
98
96
94
92
90
88
86
84
82
25
75
0
50
100
AMBIENT TEMPERATURE (°C)
125
80
100
100µF
10µF
100µF
10µF
1µF
I
L
= 1mA
Power Efficiency vs Oscillator
Frequency, V
+
= 5V
T
A
= 25°C
C1 = C2
POWER EFFICIENCY (%)
100
98
96
94
92
90
88
86
84
82
100k
1044a G02
Power Efficiency vs Oscillator
Frequency, V
+
= 10V
100µF
10µF
I
L
= 1mA
10µF
T
A
= 25°C
C1 = C2
100µF
I
L
= 15mA
I
L
= 15mA
1µF
1µF
1µF
100k
1044a G03
1k
10k
OSCILLATOR FREQUENCY (Hz)
80
100
1k
10k
OSCILLATOR FREQUENCY (Hz)
1044a G01
Output Resistance vs Oscillator
Frequency, V
+
= 5V
500
C1 = C2 = 10µF
T
A
= 25°C
I
L
= 10mA
OUTPUT RESISTANCE ( )
500
Output Resistance vs Oscillator
Frequency, V
+
= 10V
POWER CONVERSION EFFICIENCY (%)
T
A
= 25°C
I
L
= 10mA
100
90
80
70
60
50
40
30
20
10
0
Power Conversion Efficiency vs
Load Current, V
+
= 2V
P
EFF
T
A
= 25°C
C1 = C2 = 10µF
f
OSC
= 1kHz
10
9
8
SUPPLY CURRENT (mA)
7
I
S
6
5
4
3
2
1
0
1
4
3
2
5
LOAD CURRENT (mA)
6
7
0
OUTPUT RESISTANCE ( )
400
400
300
200
C1 = C2 = 1µF
300
200
C1 = C2
= 100µF
C1 = C2
= 10µF
C1 = C2 = 1µF
100
C1 = C2 = 100µF
0
100
1k
10k
OSCILLATOR FREQUENCY (Hz)
100k
1044a G04
100
0
100
1k
10k
OSCILLATOR FREQUENCY (Hz)
100k
1044a G05
1044a G06
Power Conversion Efficiency vs
Load Current, V
+
= 5V
100
POWER CONVERSION EFFICIENCY (%)
90
80
70
60
50
40
30
20
10
0
0
10
40
30
20
50
LOAD CURRENT (mA)
60
70
I
S
P
EFF
T
A
= 25°C
C1 = C2 = 10µF
f
OSC
= 5kHz
100
POWER CONVERSION EFFICIENCY (%)
90
80
SUPPLY CURRENT (mA)
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
Power Conversion Efficiency vs
Load Current, V
+
= 10V
300
P
EFF
I
S
270
240
SUPPLY CURRENT (mA)
210
180
150
120
90
T
A
= 25°C
C1 = C2 = 10µF
f
OSC
= 20kHz
0
20
80
60
40
100
LOAD CURRENT (mA)
120
60
30
0
140
1044a G07
1044a G08
1044afa
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For more information
www.linear.com/LTC1044A
LTC1044A
Typical perForMance characTerisTics
Output Resistance vs Supply
Voltage
1000
T
A
= 25°C
I
L
= 3mA
OUTPUT VOLTAGE (V)
2.5
2.0
1.5
C
OSC
= 100pF
100
C
OSC
= 0pF
1.0
0.5
0
– 0.5
–1.0
–1.5
–2.0
10
0
1
2
3
4 5 6 7 8 9 10 11 12
SUPPLY VOLTAGE (V)
1044a G09
Output Voltage vs Load Current,
V
+
= 2V
T
A
= 25°C
f
OSC
= 1kHz
OUTPUT VOLTAGE (V)
5
4
3
2
1
0
–1
–2
–3
–4
0
1
2
3 4 5 6 7 8
LOAD CURRENT (mA)
9
10
–5
Output Voltage vs Load Current,
V
+
= 5V
T
A
= 25°C
f
OSC
= 5kHz
OUTPUT RESISTANCE ( )
SLOPE = 250
SLOPE = 80
–2.5
0
10 20 30 40 50 60 70 80 90 100
LOAD CURRENT (mA)
1044a G11
1044a G10
Output Voltage vs Load Current,
V
+
= 10V
10
8
6
OUTPUT VOLTAGE (V)
4
2
0
–2
–4
–6
–8
–10
0
SLOPE = 45
T
A
= 25°C
f
OSC
= 20kHz
OUTPUT RESISTANCE ( )
400
360
320
280
240
200
160
120
80
40
Output Resistance vs
Temperature
C1 = C2 = 10µF
V
+
= 2V, f
OSC
= 1kHz
OSCILLATOR FREQUENCY (Hz)
100k
Oscillator Frequency as a
Function of C
OSC
, V
+
= 5V
T
A
= 25°C
PIN 1 = V
+
10k
1k
PIN 1 = OPEN
100
V = 5V, f
OSC
= 5kHz
+
10 20 30 40 50 60 70 80 90 100
LOAD CURRENT (mA)
1044a G12
V
+
= 10V, f
OSC
= 20kHz
0
50
25
0
75 100
–55 –25
AMBIENT TEMPERATURE (°C)
125
10
1
100
1000
10000
10
EXTERNAL CAPACITOR (PIN 7 TO GND)(pF)
1044a G14
1044a G13
100k
Oscillator Frequency as a
Function of C
OSC
, V
+
= 10V
V
+
= 10V
T
A
= 25°C
PIN 1 = V
+
100k
Oscillator Frequency vs Supply
Voltage
T
A
= 25°C
C
OSC
= 0pF
35
30
25
20
15
10
5
Oscillator Frequency vs
Temperature
C
OSC
= 0pF
OSCILLATOR FREQUENCY (kHz)
OSCILLATOR FREQUENCY (Hz)
10k
OSCILLATOR FREQUENCY (Hz)
10k
V
+
= 10V
1k
PIN 1 = OPEN
1k
100
V
+
= 5V
10
1
100
1000
10000
10
EXTERNAL CAPACITOR (PIN 7 TO GND)(pF)
1044a G15
0.1k
0
1
2
3
4 5 6 7 8 9 10 11 12
SUPPLY VOLTAGE (V)
1044a G16
0
–55 –25
50
100
25
75
0
AMBIENT TEMPERATURE (°C)
125
1044a G17
1044afa
For more information
www.linear.com/LTC1044A
5
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