ICM7216DIPI Intersil, ICM7216DIPI Datasheet - Page 8

• 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

9.
INPUT A OR
Frequency (f
Period (t
Ratio (f
INPUT A
FIGURE 6. WAVEFORM FOR GUARANTEED MINIMUM
FIGURE 7. WAVEFORM FOR GUARANTEED MINIMUM
FUNCTION
INPUT B
A
A
/f
4.5V
0.5V
)
B
)
4.5V
0.5V
A
f
FREQUENCY RATIO, UNIT COUNTER
f
AND TIME INTERVAL
)
TABLE 2. 7216B INPUT ROUTING
A
B
(MAX) FUNCTION = FREQUENCY,
(MAX) AND f
Input A
Oscillator
Input A
COUNTER
INTERNAL OR
50ns MIN
OSCILLATOR
MAIN
EXTERNAL
INPUT A
INPUT B
INPUT A
100Hz
A
250ns
FIGURE 8. SIMPLIFIED BLOCK DIAGRAM OF FUNCTIONS IMPLEMENTATION
MIN
(MAX) FOR FUNCTION = PERIOD
8
100Hz (Oscillator ∏÷10
10
Input A
Input B
MEASURED
INTERVAL
4
REFERENCE COUNTER
)
250ns
MIN
INTERNAL CONTROL
INTERNAL CONTROL
t r = t f = 10ns
50ns MIN
SELECTOR
SELECTOR
COUNTED
TRANSITIONS
INPUT
INPUT
ICM7216B, ICM7216D
t r = t f = 10s
5
or
INTERNAL CONTROL
Function Input
The six functions that can be selected are: Frequency,
Period, Time Interval, Unit Counter, Frequency Ratio and
Oscillator Frequency. This input is available on the
lCM7216B only.
The implementation of different functions is done by routing
the different signals to two counters, called “Main Counter”
and “Reference Counter”. A simplified block diagram of the
device for functions realization is shown in Figure 8. Table 2
shows which signals will be routed to each counter in
different cases. The output of the Main Counter is the
information which goes to the display. The Reference
Counter divides its input by 1, 10, 100 and 1000. One of
these outputs will be selected through the range selector
and drive the enable input of the Main Counter. This means
that the Reference Counter, along with its associated blocks,
directs the Main Counter to begin counting and determines
the length of the counting period. Note that Figure 8 does not
show the complete functional diagram (See the Functional
Block Diagram). After the end of each counting period, the
output of the Main Counter will be latched and displayed,
then the counter will be reset and a new measurement cycle
will begin. Any change in the FUNCTION INPUT will stop the
present measurement without updating the display and then
initiate a new measurement. This prevents an erroneous first
reading after the FUNCTION INPUT is changed. In all cases,
the 1-0 transitions are counted or timed.
Time Interval
(A→B)
Unit Counter
(Count A)
Osc. Freq.
(f
OSC
FUNCTION
)
TABLE 2. 7216B INPUT ROUTING
CLOCK
ENABLE
CLOCK
REFERENCE COUNTER
INTERNAL CONTROL
Oscillator
Input A
Oscillator
RANGE SELECTOR
COUNTER
÷1
MAIN COUNTER
MAIN
÷10
÷100 ÷1000
Input A
Input B
Not Applicable
100Hz (Oscillator ∏÷10
10
4
REFERENCE COUNTER
)
5
or