TC7126CPL Microchip Technology, TC7126CPL Datasheet - Page 14

• Manufacturer Part Number: TC7126CPL
• Description: IC ADC 3 1/2DGT LCD DVR 40-DIP
• Manufacturer: Microchip Technology

Specifications of TC7126CPL

• Display Type: LCD
• Configuration: 7 Segment
• Digits Or Characters: A/D 3.5 Digits
• Current - Supply: 55µA
• Voltage - Supply: 9V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 40-DIP (0.600", 15.24mm)
• Resolution (bits): 3.5bit
• Input Channel Type: Differential
• Data Interface: Parallel
• Supply Voltage Range - Analogue: 9V
• Supply Current: 55µA
• No. Of Pins: 40
• Operating Temperature Range: 0°C To +70°C
• Digital Ic Case Style: DIP
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Interface: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: TC7126CPLR; TC7126CPLR

TC7126/A
7.0
(Pin Numbers Refer to the 40-Pin PDIP.)
7.1
The TC7126A is designed with true differential inputs
and accepts input signals within the input stage
Common mode voltage range (V
V+ – 1V to V- + 1V. Common mode voltages are
removed from the system when the TC7126A operates
from a battery or floating power source (isolated from
measured system), and V
common (V
In systems where Common mode voltages exist, the
TC7126A’s 86 dB Common mode rejection ratio
minimizes error. Common mode voltages do, however,
affect the integrator output level. A worst-case condi-
tion exists if a large positive V
with a full scale negative differential signal. The
negative signal drives the integrator output positive
along with V
the integrator output swing can be reduced below the
recommended 2V full scale swing. The integrator
output will swing within 0.3V of V+ or V- without
increased linearity error.
FIGURE 7-2:
DS21458C-page 14
DEVICE PIN FUNCTIONAL
DESCRIPTION
Differential Signal Inputs
V
IN
COM
CM
+ (Pin 31), V
(see Figure 7-1). For such applications,
) (see Figure 7-2).
V+
Source
Power
V-
Common Mode Voltage Removed in Battery Operation with V
GND
IN
V+
IN
- is connected to analog
V-
Measured
CM
System
- (Pin 30)
CM
exists in conjunction
GND
). Typical range is
ANALOG
COMMON
V
V
V
IN
IN
BUFF
+
-
V
TC7126A
REF
C
FIGURE 7-1:
Reduces Available Integrator Swing (V
7.2
The reference voltage can be generated anywhere
within the V+ to V- power supply range.
To prevent rollover type errors being induced by large
Common mode voltages, C
compared to stray node capacitance.
The TC7126A offers a significantly improved analog
common
provides a very stable voltage, suitable for use as a ref-
erence. The temperature coefficient of analog common
is typically 35ppm/°C for the TC7126A and 80 ppm/°C
for the TC7126.
AZ
-
V
–
+
V
V
REF
CM
IN
V
+
INT
V+
Differential Reference
V
+
REF
temperature
Segment
+
–
9V
Drive
Input
Buffer
POL
+ (Pin 36), V
OSC1
OSC3
OSC2
Where:
V-
BP
Common Mode Voltage
V
C
R
© 2006 Microchip Technology Inc.
I
t
I
I
I
R
coefficient.
=
= Integration capacitor
= Integration resistor
= Integration time =
I
LCD
IN
R I C I
= Analog Common
REF
REF
t I
- (Pin 35)
[
should be large
V
–
+
CM
C
This
Integrator
I
– V
COM
IN
4000
F
potential
OSC
[
≠ V
V
IN
I
)