LTC1043
Dual Precision
Instrumentation Switched Capacitor
Building Block
FEATURES
DESCRIPTIO
Instrumentation Front End with 120dB CMRR The LTC 1043 is a monolithic, charge-balanced, dual
Precise, Charge-Balanced Switching switched capacitor instrumentation building block. A pair
Operates from 3V to 18V of switches alternately connects an external capacitor to
Internal or External Clock an input voltage and then connects the charged capacitor
Operates up to 5MHz Clock Rate across an output port. The internal switches have a
Low Power break-before-make action. An internal clock is provided
Two Independent Sections with One Clock and its frequency can be adjusted with an external
capacitor. The LTC1043 can also be driven with an external
U
CMOS clock.
APPLICATIO S
The LTC1043, when used with low clock frequencies,
Precision Instrumentation Amplifiers
provides ultra precision DC functions without requiring
Ultra Precision Voltage Inverters, Multipliers
precise external components. Such functions are
and Dividers
differential voltage to single-ended conversion, voltage
VF and FV Converters
inversion, voltage multiplication and division by 2, 3, 4, 5,
Sample-and-Hold
etc. The LTC1043 can also be used for precise VF and
Switched Capacitor Filters
FV circuits without trimming, and it is also a building
block for switched capacitor filters, oscillators and
modulators.
The LTC1043 is manufactured using Linear Technologys
TM
enhanced LTCMOS silicon gate process.
, LTC and LT are registered trademarks of Linear Technology Corporation.
LTCMOS is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
Instrumentation Amplifier CMRR vs Frequency
5V
140
C = C = 1F
4 S H
5V
120
8
3
7 8 +
1
1F
1/2 LTC1013 V 100
OUT
C
H
2
11
4
80
DIFFERENTIAL 1F
5V
C
S
INPUT (EXTERNAL)
60
12
1F
40
13 14
20
R1 R2
100 1k 10k 100k
FREQUENCY OF COMMON MODE SIGNAL
CMRR > 120dB AT DC
16 1/2 LTC1043
LTC1043 TA02
CMRR > 120dB AT 60Hz
0.01F DUAL SUPPLY OR SINGLE 5V
GAIN = 1 + R2/R1
17
LTC1043 TA01 V 150V
OS
5V
V
OS
2V/C
T
COMMON MODE INPUT VOLTAGE INCLUDES THE SUPPLIES
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CMRR (dB)
U
ULTC1043
UUW
ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO
(Note 1)
TOP VIEW
ORDER PART
Supply Voltage ........................................................ 18V
1 18 S3B
SH NUMBER
+ B
Input Voltage at Any Pin .......... 0.3V V V + 0.3V
IN
+
2 17 V
C
B
Operating Temperature Range
LTC1043CN
3 16 C
C
B OSC
LTC1043C ................................... 40C T 85C
LTC1043CSW
A +
4 15 S4B
V
LTC1043M (OBSOLETE).............55C T 125C
A
5 14 S4A
S2B
Storage Temperature Range ................. 65C to 150C
6 13 S3A
S1B
Lead Temperature (Soldering, 10 sec).................. 300C
7 12 C
S1A
A
+
8 11 C
S2A
A
9 10 SH
NC
A
N PACKAGE SW PACKAGE
18-LEAD PDIP
18-LEAD PLASTIC SO
T = 100C, = 100C/W PACKAGE (N)
JMAX JA
T = 150C, = 85C/W PACKAGE (SW)
JMAX JA
D PACKAGE
LTC1043MD
18-LEAD SIDE BRAZED (HERMETIC)
OBSOLETE PACKAGE
Consider the N18 Package as an Alternate Source
LTC1043 POI01
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The denotes specifications which apply over the full operating temperature
+
range, otherwise specifications are at T = 25C. V = 10V, V = 0V, LTC1043M operates from 55C T 125C; LTC1043C operates from
A A
40C T 85C, unless otherwise noted.
A
LTC1043M LTC1043C
SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
I Power Supply Current Pin 16 Connected High or Low 0.25 0.4 0.25 0.4 mA
S
0.7 0.7 mA
C (Pin 16 to V ) = 100pF 0.4 0.65 0.4 0.65 mA
OSC
11mA
I OFF Leakage Current Any Switch, Test Circuit 1 (Note 2) 6 100 6 100 pA
I
6 500 6 nA
R ON Resistance Test Circuit 2, V = 7V, 1 = 0.5mA 240 400 240 400
ON IN
+
V = 10V, V = 0V 700 700
R ON Resistance Test Circuit 2, V = 3.1V, 1 = 0.5mA 400 700 400 700
ON IN
+
V = 5V, V = 0V 11k
f Internal Oscillator Frequency C (Pin 16 to V ) = 0pF 185 185 kHz
OSC OSC
C (Pin 16 to V ) = 100pF 20 34 50 20 34 50 kHz
OSC
Test Circuit 3 15 75 15 75 kHz
+
I Pin Source or Sink Current Pin 16 at V or V 40 70 40 70 A
OSC
100 100 A
Break-Before-Make Time 25 25 ns
Clock to Switching Delay C Pin Externally Driven 75 75 ns
OSC
f Max External CLK Frequency C Pin Externally Driven with CMOS Levels 5 5 MHz
M OSC
+
CMRR Common Mode Rejection Ratio V = 5V, V = 5V, 5V < V < 5V 120 120 dB
CM
DC to 400Hz
Note 1: Absolute Maximum Ratings are those values beyond which the life
Note 2: OFF leakage current is guaranteed but not tested at 25C.
of a device may be impaired.
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