MAX1454_11 Datasheet, PDF (22/25 Pages) Maxim Integrated Products – Precision Sensor Signal Conditioner with Overvoltage Protection

MAX1454
Precision Sensor Signal Conditioner
with Overvoltage Protection
Applications Information
Typical Ratiometric Operating Circuit
Ratiometric output configuration provides an output that is
proportional to the power-supply voltage. This output can
then be applied to a ratiometric ADC to produce a digital
value independent of supply voltage. Ratiometricity is an
important consideration for battery-operated instruments,
automotive, and some industrial applications.
The device provides a high-performance ratiometric output
with a minimum number of external components (Figure 5).
These external components include the following:
U Supply bypass capacitor (V_DDX)
U 0.1FF output capacitor (V_DD)
U Optional output capacitor (OUT/DIO)
Typical Nonratiometric Operating Circuit
(6V DC < V_PWR < 40V DC)
Nonratiometric output configuration enables the sensor
power to vary over a wide range. A high-performance
voltage reference, such as the MAX15006B, is incorpo-
rated in the circuit to provide a stable supply and refer-
ence for device operation. A typical nonratiometric circuit
is shown in Figure 6. Nonratiometric operation is valuable
when a wide range of input voltage is to be expected
and the system ADC or readout device does not enable
ratiometric operation.
15
VDDX
5
14
BDR
V_DD
6
IN-
13
VDDF
MAX1454
4
12
IN+ OUT/DIO
GND
9
0.1µF
Figure 5. Basic Ratiometric Output Configuration
+5V
0.1µF
OUT/DIO
0.01µF
GND
15
5
VDDX
14
BDR
6
IN-
VDD
13
VDDF
MAX1454
4
IN+
OUT/DIO ¹²
8 ^MAX15006B 1
OUT
IN
GND
5
2N4392
VPWR
+6V TO +40V
OUT/DIO
GND
0.1µF
2.2µF
9
0.1µF
0.01µF
GND
Figure 6. Basic Nonratiometric Output Configuration
���������������������������������������������������������������� Maxim Integrated Products   22