MAX1365 Datasheet, PDF (17/25 Pages) Maxim Integrated Products – Stand-Alone, 4.5-/3.5-Digit Panel Meters with 4-20mA Output

Stand-Alone, 4.5-/3.5-Digit Panel Meters
with 4–20mA Output
LED
1----
19,999
2
1
0
-0
-1
-2
-19,999
-1----
-2V
-100µV 0 100µV
+2V
ANALOG INPUT VOLTAGE
Figure 7. MAX1365 Transfer Function—±2V Range
LED
1----
19,999
2
1
0
-0
-1
-2
-19,999
-1----
-200mV
-10µV 0 10µV
+200mV
ANALOG INPUT VOLTAGE
Figure 8. MAX1365 Transfer Function—±200mV Range
Transfer Functions
ADC Transfer Functions
Figures 7–10 show the transfer functions of the
MAX1365/MAX1367. The output data is stored in the
ADC data register in two’s complement.
The transfer function for the MAX1365 with AIN+ - AIN-
≥ 0 and RANGE = GND is:
(1)
COUNT
=
1.024


V_AIN+
V_REF+
−
−
V_AIN−
V_REF−

x 20,000_
LED
1---
1999
2
1
0
-0
-1
-2
-1999
-1---
-200mV
-100µV 0 100µV
+200mV
ANALOG INPUT VOLTAGE
Figure 9. MAX1367 Transfer Function—±200mV Range
LED
1---
1999
2
1
0
-0
-1
-2
-1999
-1---
-2V
-1mV 0 1mV
+2V
ANALOG INPUT VOLTAGE
Figure 10. MAX1367 Transfer Function—±2V Range
The transfer function for the MAX1365 with AIN+ - AIN-
< 0 and RANGE = GND is:
(2)
COUNT
=
1.024


V_AIN+
V_REF+
−
−
V_AIN−
V_REF−
x

20,000_ +1
The transfer function for the MAX1367 with AIN+ - AIN-
≥ 0 and RANGE = GND is:
(3)
COUNT
=
1.024


V_AIN+
V_REF+
−
−
V_AIN−
V_REF−

x 2000_
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