CAV414 Datasheet, PDF (4/6 Pages) Analog Microelectronics – Converter IC for Capacitive Signals

Converter IC for Capacitive Signals CAV414
BOUNDARY CONDITIONS
Parameter
Current Definition of Ref. Oscillator
Current Adjustment of Cap. Integrator 1
Current Adjustment of Cap. Integrator 2
Lowpass Stage Resistor Sum
Output Stage Resistor Sum
Reference Voltage 5V
Reference Voltage 2V (only for internal use)
Lowpass Capacitance 1
Lowpass Capacitance 2
Oscillator Capacitance
Symbol
RCOSC
RCX1
RCX2
RL1 + RL2
R1 + R2
CREF
CVM
CL1
CL2
COSC
Min.
190
350
350
90
90
1.9
80
100⋅CX1
100⋅CX1
COSC =1.55⋅CX1
Typ.
200
400
400
2.2
100
200⋅CX1
200⋅CX1
COSC =1.60⋅CX1
Max.
210
450
450
200
200
5
120
COSC =1.65⋅CX1
Unit
kΩ
kΩ
kΩ
kΩ
kΩ
µF
nF
Note: The system performance over temperature forces that the resistors R_CX1, R_CX2 and R_OSC have the same temperature
coefficient and a very close placement of them in the circuit. The capacities C_X1, C_X2 and C_OSC are also forced to
have the same temperature coefficient and a very close placement of them in the circuit.
FUNCTIONAL DIAGRAM
12
C_OSC
Reference
Oscillator
16
C_X1
14
C_X2
Integrator 1
V_CX1
Integrator 2
V_CX2
Signal Conditioning _VCX,DIFF
R₀₁
R₀₂
V_LPOUT
IA
V_M
CAV414
9
V_DIFF
OP
8
7
10
Voltage/Current
Reference
11
Figure 2
15
C_L1
13
C_L2
45
R_L1
R_L2
6
2
3
1
C_VM
R_CX1
R_CX2
R_OSC
VCC
OUT
R₁
R₂
GND
C_REF
analog microelectronics
January 2001
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