LTC6943 Datasheet, PDF (1/16 Pages) Linear Technology – Micropower, Dual Precision Instrumentation Switched Capacitor Building Block

FEATURES
■ _{Low Power, IS = 60µA(Max)}
■ _{Robust, Latch Up Proof}
■ _{Instrumentation Front End with 120dB CMRR}
■ _{Precise, Charge-Balanced Switching}
■ _{Operates from 5V to 18V}
■ _{Internal or External Clock}
■ _{Operates up to 5MHz Clock Rate}
■ _{Two Independent Sections with One Clock}
■ _{Tiny SSOP-16 PaUckage}
APPLICATIO S
■ _{Ultra Precision Voltage Inverters, Multipliers}
and Dividers
■ _{V–F and F–V Converters}
■ _{Sample-and-Hold}
■ _{Current Sources}
■ _{Precision Instrumentation Amplifiers}
, LTC and LT are registered trademarks of Linear Technology Corporation.
LTCMOS is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
Precision Voltage Controlled Current Source
with Ground Referred Input and Output
5V
INPUT 3 ₊
5
0V TO 3.7V
1
LTC2050
4_–
2
0.68µF
5V
1k
3
1/2 LTC6943
7
6
9
1µF
1µF
1k
10
12
11
15
14
0.001µF
I_OUT =
V_IN
1000Ω
OPERATES FROM A
SINGLE 5V SUPPLY
6943 • TA01a
LTC6943
Micropower, Dual Precision
Instrumentation Switched
Capacitor Building Block
DESCRIPTIO
The LTC^®6943 is a monolithic, charge-balanced, dual
switched capacitor instrumentation building block. A pair
of switches alternately connects an external capacitor to
an input voltage and then connects the charged capacitor
across an output port. The internal switches have a
break-before-make action. An internal clock is provided
and its frequency can be adjusted with an external
capacitor. The LTC6943 can also be driven with an external
CMOS clock.
The LTC6943, when used with low clock frequencies,
provides ultra precision DC functions without requiring
precise external components. Such functions are
differential voltage to single-ended conversion, voltage
inversion, voltage multiplication and division by 2, 3, 4, 5,
etc.
The LTC6943 is manufactured using Linear Technology’s
enhanced LTCMOS^TM silicon gate process, and it is func-
tionally compatible with the LTC1043.
Precision Current Sensing in Supply Rails
I
POSITIVE OR
NEGATIVE RAIL
E
R_SHUNT
1/2 LTC6943
11
12
10
1µF
1µF
9
E I= ^E
R_SHUNT
6
7
14
15
0.01µF
6943 • TA01b
6943f
1