TC7106/A/TC7107/A
DS21455D-page 6
2008 Microchip Technology Inc.
2.0
PIN DESCRIPTIONS
The descriptions of the pins are listed in
Table 2-1.
TABLE 2-1:
PIN FUNCTION TABLE
Pin Number
(40-Pin PDIP)
Normal
Pin No.
(40-Pin PDIP)
(Reversed
Symbol
Description
1
(40)
V+
Positive supply voltage.
2
(39)
D1
Activates the D section of the units display.
3
(38)
C1
Activates the C section of the units display.
4
(37)
B1
Activates the B section of the units display.
5
(36)
A1
Activates the A section of the units display.
6
(35)
F1
Activates the F section of the units display.
7
(34)
G1
Activates the G section of the units display.
8
(33)
E1
Activates the E section of the units display.
9
(32)
D2
Activates the D section of the tens display.
10
(31)
C2
Activates the C section of the tens display.
11
(30)
B2
Activates the B section of the tens display.
12
(29)
A2
Activates the A section of the tens display.
13
(28)
F2
Activates the F section of the tens display.
14
(27)
E2
Activates the E section of the tens display.
15
(26)
D3
Activates the D section of the hundreds display.
16
(25)
B3
Activates the B section of the hundreds display.
17
(24)
F3
Activates the F section of the hundreds display.
18
(23)
E3
Activates the E section of the hundreds display.
19
(22)
AB4
Activates both halves of the 1 in the thousands display.
20
(21)
POL
Activates the negative polarity display.
21
(20)
BP/GND
LCD Backplane drive output (TC7106A). Digital Ground (TC7107A).
22
(19)
G3
Activates the G section of the hundreds display.
23
(18)
A3
Activates the A section of the hundreds display.
24
(17)
C3
Activates the C section of the hundreds display.
25
(16)
G2
Activates the G section of the tens display.
26
(15)
V-
Negative power supply voltage.
27
(14)
VINT
Integrator output. Connection point for integration capacitor. See INTEGRATING
CAPACITOR section for more details.
28
(13)
VBUFF
Integration resistor connection. Use a 47 k
Ω resistor for a 200 mV full scale range
and a 47 k
Ω resistor for 2V full scale range.
29
(12)
CAZ
The size of the auto-zero capacitor influences system noise. Use a 0.47 F capacitor
for 200 mV full scale, and a 0.047 F capacitor for 2V full scale. See Section 7.1 30
(11)
VIN-
The analog LOW input is connected to this pin.
31
(10)
VIN+
The analog HIGH input signal is connected to this pin.
32
(9)
ANALOG
COMMON
This pin is primarily used to set the Analog Common mode voltage for battery
operation or in systems where the input signal is referenced to the power supply. It
32)” on ANALOG COMMON for more details.
33
(8)
CREF-
See Pin 34.
34
(7)
CREF+
A 0.1 F capacitor is used in most applications. If a large Common mode voltage
exists (for example, the VIN- pin is not at analog common), and a 200 mV scale is
used, a 1 F capacitor is recommended and will hold the rollover error to 0.5 count.
35
(6)
VREF-
See Pin 36.