tc7126a Microchip Technology Inc., tc7126a Datasheet - Page 13

• Manufacturer Part Number: tc7126a
• Description: 3-1/2 Digit Analog-to-digital Converters
• Manufacturer: Microchip Technology Inc.

6.6
A full scale reading (2000 counts) requires the input
signal be twice the reference voltage.
In some applications, a scale factor other than unity
may exist between a transducer output voltage and the
required digital reading. Assume, for example, a
pressure transducer output for 2000lb/in
Rather than dividing the input voltage by two, the
reference voltage should be set to 200mV. This permits
the transducer input to be used directly.
The differential reference can also be used where a
digital zero reading is required when V
zero. This is common in temperature measuring instru-
mentation. A compensating offset voltage can be
applied between analog common and V
ducer output is connected between V
common.
© 2006 Microchip Technology Inc.
Required Full Scale Voltage*
Note:
Reference Voltage Selection
V
20mV
FS
2V
= 2V
REF
.
IN
IN
100mV
IN
is not equal to
+ and analog
V
2
-. The trans-
1V
REF
is 400mV.
TC7126/A
DS21458C-page 13