LINER LT1026CH

LT1026
Voltage Converter
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FEATURES
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DESCRIPTIO
The LT ® 1026 is a switched capacitor voltage doubler and
inverter on a single monolithic die. Capable of operating
from a 4V to 10V input, it provides ±7V to ±18V output.
Output currents of over 10mA are available. Two charge
pumps first double the input voltage then invert the
doubled voltage. Manufactured in bipolar technology, the
LT1026 is not susceptible to latchup and generates up to
36V.
Generates + and – from Single Input
Up to ±18V Output
Only Needs Four 1µF Capacitors
No Inductors
10mA Output Current Minimum
Operates Down to 4V
No Latchup
8-Pin Minidip
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APPLICATIO S
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Line Drivers
Op Amp Suppliers
Battery Splitters
RS232 Power
, LTC and LT are registered trademarks of Linear Technology Corporation.
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The LT1026 offers a convenient way of generating additional system voltages without using inductors. Powering
interface circuits, op amps or data acquisition circuitry off
logic supplies is simplified.
TYPICAL APPLICATIO
Output Voltage
Voltage Doubler and Inverter
C1
1µF
10
C = 1µF
VIN = 5V
TA = 25°C
+
8
C2
1µF
1
C1–
+VOUT
2
C2+
C1+
+
3
4
–VOUT
LT1026
C2–
–VOUT
VIN
GND
8
+
7
6
+VOUT
1µF
VIN
5
OUTPUT VOLTAGE (V)
6
4
2
0
–2
–4
–6
–8
1µF
+
–10
1026 • TA01
0
5
15
20
10
LOAD CURRENT (mA)
25
LT1026 • TA02
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LT1026
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ABSOLUTE MAXIMUM RATINGS
(Note 1)
Supply Voltage ........................................................ 10V
V + ............................................................................ 20V
V – ..........................................................................– 20V
Short-Circuit Duration ......................................... 10 sec
Operating Temperature Range
LT1026C ................................................. 0°C to 70°C
LT1026I .............................................. – 40°C to 85°C
LT1026M (OBSOLETE) ............... – 55°C to 125°C
Lead Temperature (Soldering, 10 sec)................. 300°C
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PACKAGE/ORDER INFORMATION
TOP VIEW
+VOUT
C1– 1
8
C1– 1
7 C1+
8 +VOUT
C2+ 2
C2+ 2
6
C2– 3
TOP VIEW
TOP VIEW
VIN
5
7 C1+
C2– 3
GND
6 VIN
–VOUT 4
4
–VOUT
8 +VOUT
C2+
2
7 C1+
C2–
3
6 VIN
–VOUT 4
5 GND
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 100°C/W (N8)
TJMAX = 150°C, θJA = 150°C/W (S8)
TJMAX = 150°C, θJA = 150°C/W
TJMAX = 150°C, θJA = 150°C/W
5 GND
N8 PACKAGE
8-LEAD PDIP
J8 PACKAGE
8-LEAD CERDIP
H PACKAGE
8-LEAD TO-5 METAL CAN
C1– 1
ORDER PART
NUMBER
ORDER PART
NUMBER
ORDER PART
NUMBER
S8 PART
MARKING
LT1026CH
LT1026MH
LT1026CJ8
LT1026MJ8
LT1026CN8
LT1026CS8
LT1026IS8
1026
1026I
OBSOLETE PACKAGES
Consider the N8 or S8 Packages for Alternate Source
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C.
PARAMETERS
CONDITIONS
MIN
TYP
Output Voltage
VIN = 4V
(Note 2)
IL = 0mA
IL = 0mA
IL = 10mA
IL = – 10mA
Positive
Negative
Positive
Negative
VIN = 5V
IL = 15mA
IL = – 15mA
VIN = 10V
MAX
UNITS
●
●
●
●
6.5
–6
5.25
– 4.5
7
– 6.7
5.7
–5
V
V
V
V
Positive
Negative
●
●
6.25
– 5.5
7
– 6.2
V
V
IL = 0mA
IL = 0mA
IL = 10mA
IL = – 10mA
IL = 15mA
IL = – 15mA
Positive
Negative
Positive
Negative
Positive
Negative
●
●
●
●
●
●
18
– 17.7
16
– 15.3
15.25
– 14.5
18.5
– 18
17.6
– 17
17
– 16.5
V
V
V
V
V
V
VIN = 5V
IL = 10mA, – 10mA
Positive
Negative
●
●
6.25
– 5.5
7.2
– 6.5
V
V
VIN = 10V
IL = 10mA, – 10mA
Positive
Negative
●
●
15
– 14.25
16.8
– 15.75
V
V
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LT1026
ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C.
PARAMETERS
CONDITIONS
Supply Current
VIN = 4V
VIN = 10V
MIN
IL = 0mA
IL = 0mA
●
●
TYP
MAX
UNITS
7
15
12.5
30
mA
mA
Note 1: Absolute Maximum Ratings are those values beyond which the life of
a device may be impaired.
Note 2: VIN min = – 4.5 for TA ≤ 40°C
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TYPICAL PERFORMANCE CHARACTERISTICS
Load Regulation (Both Outputs
Loaded)
Load Regulation for Positive
Loading
C = 1µF
VIN = 5V
TA = 25°C
8
OUTPUT VOLTAGE (V)
4
2
0
–2
–4
10
8
8
6
6
4
2
–2
–4
–6
–6
–8
–8
–10
0
5
15
20
10
LOAD CURRENT (mA)
–10
25
C = 1µF
VIN = 5V
TA = 25°C
0
IL = 0
0
5
Supply Current
SUPPLY CURRENT (mA)
SUPPLY CURRENT (mA)
–4
30
15
C = 22µF
VIN = 5V
TA = 25°C
NEGATIVE
OUTPUT
LOADED
25
LT1026 • TPC04
15
20
10
LOAD CURRENT (mA)
25
LT1026 • TPC03
40
C = 22µF
VIN = 5V
TA = 25°C
POSITIVE
OUTPUT
LOADED
50
30
20
40
30
20
10
0
10
15
20
OUTPUT CURRENT (mA)
5
Supply Current
10
0
0
60
50
45
5
–2
Supply Current
C = 22µF
VIN = 5V
TA = 25°C
BOTH OUTPUTS
LOADED
C = 1µF
VIN = 5V
TA = 25°C
0
–10
25
60
0
2
LT1026 • TPC02
90
60
4
–8
15
20
10
LOAD CURRENT (mA)
LT1026 • TPC01
75
IL = 0
–6
SUPPLY CURRENT (mA)
OUTPUT VOLTAGE (V)
6
10
OUTPUT VOLTAGE (V)
10
Load Regulation for Negative
Loading
0
0
5
10
15
20
OUTPUT CURRENT (mA)
25
LT1026 • TPC05
0
5
10
15
20
OUTPUT CURRENT (mA)
25
LT1026 • TPC06
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LT1026
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TYPICAL PERFORMANCE CHARACTERISTICS
Ripple
Output Voltage vs Temperature
10
60
VIN = 5V
IL = 5mV
BOTH OUTPUTS
8
6
OUTPUT VOLTAGE (V)
RIPPLE (mVP-P)
50
40
30
20
4
2
0
–2
C = 22µF
VIN = 5V
IL = 1mA
–4
–6
10
–8
0
1.0
2.2
47
4.7
10
22
OUTPUT CAPACITOR (µF)
100
1026 • TPC07
–10
–50 –25
50
25
0
75
TEMPERATURE (°C)
100
125
LT1026 • TPC08
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APPLICATIONS INFORMATION
The LT1026 is a nonregulating voltage converter that
converts a single input voltage into both a positive and
negative output at up to 15mA. A positive input voltage is
first doubled and then the doubled voltage is inverted. The
voltage output level is dependent on both the input voltage
and the output loading. The total output current available
depends on the individual loading of the outputs since
loading on one output affects the load and the voltage of
the other.
Only four external components are needed for operation.
Two charge pump capacitors and two output storage
capacitors. Nominal value for these capacitors is 1µF, but
the LT1026 will operate (with reduced performance) down
to 0.1µF. Higher value capacitors (22µF) will reduce ripple
and slightly lower output impedance. For higher output
currents the outputs of several converters may be paralleled with common output capacitors.
The substrate diodes are an inherent part of the IC, and
must always be reversed biased to isolate the individual
transistors. In the LT1026 the substrate is tied to the
negative output. If the negative output is not used, such as
when only the voltage doubler output is needed, – VOUT
must be tied to ground so the substrate diodes are
properly biased. The substrate diodes must never become
forward biased even during overload conditions. For example, pulling – VOUT positive with respect to ground can
forward bias the substrate diodes. Clamping the substrate
to ground with an external diode would be needed to
ensure proper operation and prevent the substrate from
carrying any current.
No overload protection is included on the LT1026. Neither
output is damaged by momentary shorts, but during
sustained shorts the resulting high current flow will overheat the IC.
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LT1026
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TYPICAL APPLICATIONS
Positive to Negative Converter
1
C1–
2
C2+
+
1µF
3
4
–VOUT
+VOUT
C1+
LT1026
C2–
VIN
–VOUT
GND
8
1µF
NC
+
NC
Voltage Doubler
7
1
6
C1–
VIN
2
5
C2+
C2–
+
4
1026 • TA03
C1+
LT1026
3
1µF
+VOUT
VIN
–VOUT
GND
8
+
7
6
VOUT
1µF
VIN
5
1026 • TA04
Standard Configuration Voltage Doubler and Inverter
Voltage Quadrupler
C1
1µF
C1
1µF
2
+
3
4
–VOUT
+VOUT
C2+
C1+
LT1026
C2–
VIN
–VOUT
GND
8
+
7
6
1
+VOUT
2
1µF
C2
1µF
VIN
+
3
5
4
C1–
+VOUT
8
+
7
C1+
C2+
LT1026
C2–
VIN
–VOUT
GND
+VOUT
1µF
6
5
VIN (FLOATING)
+
1µF
+
1026 • TA05
1026 • TA06
1µF
Parallel Converters for Higher Output Current and Lower Output Impedance
C1
1µF
C1
1µF
2
C2
1µF
+
3
4
C1–
+
+
1
+VOUT
C2+
C1+
LT1026
C2–
–VOUT
VIN
GND
8
1
7
2
6
VIN
+
C2
1µF
3
5
4
C1–
+VOUT
C2+
C1+
LT1026
C2–
–VOUT
VIN
GND
8
+
7
6
+VOUT
1µF
VIN
5
1026 • TA07
–VOUT
+
C2
1µF
C1–
+
+
1
1µF
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LT1026
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TYPICAL APPLICATIONS
5V Powered RS232 Line Driver
C1
1µF
+
1
C1–
+VOUT
2
C2+
C1+
+
3
4
LT1026
C2–
VIN
–VOUT
GND
8
+
7
6
LT1030
1µF
5VIN
5
LOGIC
LINE
+
1026 • TA08
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PACKAGE DESCRIPTION
H Package
8-Lead TO-5 Metal Can (.230 Inch PCD)
(Reference LTC DWG # 05-08-1321)
.335 – .370
(8.509 – 9.398)
DIA
.305 – .335
(7.747 – 8.509)
.040
(1.016)
MAX
.027 – .045
(0.686 – 1.143)
45°TYP
.050
(1.270)
MAX
SEATING
PLANE
.165 – .185
(4.191 – 4.699)
GAUGE
PLANE
.010 – .045*
(0.254 – 1.143)
.028 – .034
(0.711 – 0.864)
PIN 1
.230
(5.842)
TYP
REFERENCE
PLANE
.500 – .750
(12.700 – 19.050)
H8 (TO-5) 0.230 PCD 0801
.110 – .160
(2.794 – 4.064)
INSULATING
STANDOFF
.016 – .021**
(0.406 – 0.533)
*LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE
AND THE SEATING PLANE
.016 – .024
**FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS
(0.406 – 0.610)
OBSOLETE PACKAGE
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LT1026
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PACKAGE DESCRIPTION
J8 Package
8-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
.300 BSC
(7.62 BSC)
CORNER LEADS OPTION
(4 PLCS)
.008 – .018
(0.203 – 0.457)
.015 – .060
(0.381 – 1.524)
.023 – .045
(0.584 – 1.143)
HALF LEAD
OPTION
0° – 15°
.045 – .068
(1.143 – 1.650)
FULL LEAD
OPTION
.405
(10.287)
MAX
.005
(0.127)
MIN
.200
(5.080)
MAX
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NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE
OR TIN PLATE LEADS
.014 – .026
(0.360 – 0.660)
5
.025
(0.635)
RAD TYP
.220 – .310
(5.588 – 7.874)
1
.045 – .065
(1.143 – 1.651)
6
7
2
3
4
J8 0801
.125
3.175
MIN
.100
(2.54)
BSC
OBSOLETE PACKAGE
N8 Package
8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
.300 – .325
(7.620 – 8.255)
.008 – .015
(0.203 – 0.381)
(
+.035
.325 –.015
+0.889
8.255
–0.381
.400*
(10.160)
MAX
.130 ± .005
(3.302 ± 0.127)
.045 – .065
(1.143 – 1.651)
.065
(1.651)
TYP
)
8
7
6
5
1
2
3
4
.255 ± .015*
(6.477 ± 0.381)
.120
(3.048) .020
MIN
(0.508)
MIN
.018 ± .003
.100
(2.54)
BSC
N8 1002
(0.457 ± 0.076)
NOTE:
1. DIMENSIONS ARE
INCHES
MILLIMETERS
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
.189 – .197
(4.801 – 5.004)
NOTE 3
.010 – .020
× 45°
(0.254 – 0.508)
.008 – .010
(0.203 – 0.254)
.004 – .010
(0.101 – 0.254)
8
7
6
.045 ±.005
5
.050 BSC
0°– 8° TYP
.016 – .050
(0.406 – 1.270)
NOTE:
1. DIMENSIONS IN
.053 – .069
(1.346 – 1.752)
.014 – .019
(0.355 – 0.483)
TYP
INCHES
(MILLIMETERS)
2. DRAWING NOT TO SCALE
3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
.050
(1.270)
BSC
.150 – .157
.245
(3.810 – 3.988) MIN
NOTE 3
.228 – .244
(5.791 – 6.197)
1
2
3
4
.030 ±.005
TYP
.160 ±.005
SO8 0303
RECOMMENDED SOLDER PAD LAYOUT
1026fb
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
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LT1026
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TYPICAL APPLICATION
Regulated Converter
C1
1µF
+
1
2
+
C2
1µF
3
4
C1–
+VOUT
C2+
C1+
LT1026
C2–
–VOUT
VIN
GND
8
+
7
6
+VOUT
9
1µF
8
VIN ≥ 4V
INPUT –
3
VIN
GND
OUT
2
5V
500k
5
5
LT1020
COMP/PNP
FB
INPUT +
1µF
REFOUT
+
7
COMP/NPN
4
6
0.001µF
+
11
10µF
500k
+
10µF
0.001µF
1M
500k
500k
–5V REG 10mA
1026 • TA09
2N3904
51k
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PART NUMBER
DESCRIPTION
COMMENTS
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Can be Used as Inverter/Doubler/Divider or a Multiplier,
VIN = 1.5V to 9V, IQ = 60µA, SO-8
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IOUT to 100mA/125mA, VIN = 3.5V to 15V, Inverter,
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2.7V to 10V, > 10kV ESD, Short-Circuit and Overtemp Protection
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Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
LT/TP 0203 REV B 1K • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 1988