TC835CPI Microchip Technology, TC835CPI Datasheet - Page 8

• Manufacturer Part Number: TC835CPI
• Description: IC ADC 4 1/2DGT BCD 28-DIP
• Manufacturer: Microchip Technology

Specifications of TC835CPI

• Display Type: LED
• Configuration: 7 Segment
• Interface: BCD
• Digits Or Characters: A/D 4.5 Digits
• Current - Supply: 1mA
• Voltage - Supply: 4 V ~ 6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 28-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

TC835
4.0
4.1
The TC835 operates with differential voltages within
the input amplifier Common mode range. The input
amplifier Common mode range extends from 0.5V
below the positive supply to 1V above the negative
supply. Within this Common mode voltage range, an
86dB Common mode rejection ratio is typical.
The integrator output also follows the Common mode
voltage. The integrator output must not be allowed to
saturate. An example of a worst case condition would
be when a large positive Common mode voltage with a
near full scale negative differential input voltage is
applied. The negative input signal drives the integrator
positive when most of its swing has been used up by
the positive Common mode voltage. For these critical
applications, the integrator swing can be reduced to
less than the recommended 4V full scale swing, with
the effect of reduced accuracy. The integrator output
can swing within 0.3V of either supply without loss of
linearity.
4.2
ANALOG COMMON is used as the -INPUT return dur-
ing auto zero and de-integrate. If -INPUT is different
from ANALOG COMMON, a Common mode voltage
exists in the system. This signal is rejected by the
excellent CMRR of the converter. In most applications,
-INPUT will be set at a fixed, known voltage (power
supply common, for instance). In this application,
ANALOG COMMON should be tied to the same point,
thus removing the common-mode voltage from the
converter. The reference voltage is referenced to
ANALOG COMMON.
DS21478C-page 8
ANALOG SECTION
FUNCTIONAL DESCRIPTION
Differential Inputs
Analog Common Input
4.3
The REF IN input must be a positive voltage with
respect to ANALOG COMMON. A reference voltage
circuit is shown in
FIGURE 4-1:
Reference.
TC835
COMMON
Reference Voltage Input
ANALOG
V+
REF
IN
Figure
Using An External
© 2007 Microchip Technology Inc.
4-1.
10 kΩ
10 kΩ
Analog Ground
1 µF
MCP1525
2.5 V
REF
V+