MC100EP016(2002) View Datasheet(PDF) - ON Semiconductor
Part Name
Description
Manufacturer
MC100EP016 Datasheet PDF : 12 Pages
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MC10EP016, MC100EP016
Applications Information (continued)
HL L L HHHH
P7 P6 P5 P4 P3 P2 P1 P0
H PE
L CE
H TCLD
TC
CLK
COUT
CLK
COUT
Q7 Q6 Q5 Q4 Q3 Q2 Q1 Q0
Figure 4. Mod 2 to 256 Programmable Divider
To determine what value to load into the device to
accomplish the desired division, the designer simply
subtracts the binary equivalent of the desired divide ratio
from the binary value for 256. As an example for a divide
ratio of 113:
Pn’s = 256 – 113 = 8F16 = 1000 1111
where:
P0 = LSB and P7 = MSB
Forcing this input condition as per the setup in Figure 4
will result in the waveforms of Figure 5. Note that the TC
output is used as the divide output and the pulse duration is
equal to a full clock period. For even divide ratios, twice the
desired divide ratio can be loaded into the EP016 and the TC
output can feed the clock input of a toggle flip flop to create
a signal divided as desired with a 50% duty cycle.
Table 1. Preset Values for Various Divide Ratios
Divide
Ratio
Preset Data Inputs
P7 P6 P5 P4 P3 P2 P1 P0
2
HH H H H H H L
3
HH H H H H L H
4
HH H H H H L L
5
HH H H H L H H
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
112
HL L H L L L L
113
HL L L H H H H
114
HL L L H H H L
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
254
LL L L L L H L
255
LL L L L L L H
256
LL L L L L L L
A single EP016 can be used to divide by any ratio from 2
to 256 inclusive. If divide ratios of greater than 256 are
needed multiple EP016s can be cascaded in a manner similar
to that already discussed. When EP016s are cascaded to
build larger dividers the TCLD pin will no longer provide a
means for loading on terminal count. Because one does not
want to reload the counters until all of the devices in the
chain have reached terminal count, external gating of the TC
pins must be used for multiple EP016 divider chains.
CLK
PE
TC
Load
1001 0000 1001 0001 1111 1100 1111 1101
•••
1111 1110 1111 1111
Load
•••
•••
DIVIDE BY 113
Figure 5. Divide by 113 EP016 Programmable Divider Waveforms
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