ICM7216DIPI Intersil, ICM7216DIPI Datasheet - Page 7

• Manufacturer Part Number: ICM7216DIPI
• Description: IC COUNTER/TIMER FREQ 8DIG 28DIP
• Manufacturer: Intersil

Specifications of ICM7216DIPI

• Rohs Status: RoHS non-compliant
• Other names: 7216DIPI; NT5007

Typical Performance Curves
Description
INPUTS A and B
INPUTS A and B are digital inputs with a typical switching
threshold of 2V at V
peak-to-peak input signal should be at least 50% of the
supply voltage and centered about the switching voltage.
When these inputs are being driven from TTL logic, it is
desirable to use a pullup resistor. The circuit counts high to
low transitions at both inputs. (INPUT B is available only on
lCM7216B).
Note that the amplitude of the input should not exceed the
device supply (above the V DD and below the V SS ) by more
than 0.3V, otherwise the device may be damaged.
Multiplexed Inputs
The FUNCTION, RANGE, CONTROL and EXTERNAL
DECIMAL POINT inputs are time multiplexed to select the
function desired. This is achieved by connecting the
appropriate Digit driver output to the inputs. The function,
range and control inputs must be stable during the last half
of each digit output, (typically 125µs). The multiplexed inputs
are active low for the common cathode lCM7216B and
lCM7216D.
Noise on the multiplex inputs can cause improper operation.
This is particularly true when the unit counter mode of
operation is selected, since changes in voltage on the digit
drivers can be capacitively coupled through the LED diodes
to the multiplex inputs. For maximum noise immunity, a
10kΩ resistor should be placed in series with the multiplexed
inputs as shown in the application circuits.
Table 1 shows the functions selected by each digit for
these inputs.
200
150
100
50
0
0
V
DD
FIGURE 4. TYPICAL I
= 5V
DD
= 5V. For optimum performance the
1
V
7
OUT
DIGIT
(V)
vs V
-20
2
(Continued)
o
OUT
C
85
ICM7216B, ICM7216D
25
o
o
C
C
3
.
FUNCTION INPUT
(Pin 3, lCM7216B Only)
RANGE INPUT, Pin 14
CONTROL INPUT, Pin 1
External DP INPUT
(Pin 13, ICM7216D Only)
200
100
50
50
0
0
TABLE 1. MULTIPLEXED INPUT FUNCTIONS
T
A
FIGURE 5. TYPICAL I
= 25
o
C
V
DD
1
= 5V
Frequency
Period
Frequency Ratio
Time Interval
Unit Counter
Oscillator Frequency
0.01s/1 Cycle
0.1s/10 Cycles
1s/100 Cycles
10s/1K Cycles
Display Off
Display Test
1MHz Select
External Oscillator Enable
External Decimal Point
Enable
Decimal point is output for same digit
that is connected to this input.
V
OUT
DIGIT
FUNCTION
(V)
V
DD
vs V
2
= 5.5V
V
OUT
DD
= 4.5V
D4 and
DIGIT
Hold
D1
D8
D2
D5
D4
D3
D1
D2
D3
D4
D8
D2
D1
D3
3