COP87L84FH NSC [National Semiconductor], COP87L84FH Datasheet - Page 11

• Manufacturer Part Number: COP87L84FH
• Description: 8-Bit CMOS OTP Microcontrollers with 16k Memory,
• Manufacturer: NSC [National Semiconductor]

Reset
RC
Oscillator Circuits
The chip can be driven by a clock input on the CKI input pin
which can be between DC and 10 MHz. The CKO output
clock is on pin G7 (crystal configuration). The CKI input fre-
quency is divided down by 10 to produce the instruction
cycle clock (t
Figure 7 shows the Crystal and R/C oscillator diagrams.
CRYSTAL OSCILLATOR
CKI and CKO can be connected to make a closed loop crys-
tal (or resonator) controlled oscillator.
Table 1 shows the component values required for various
standard crystal values.
R/C OSCILLATOR
By selecting CKI as a single pin oscillator input, a single pin
R/C oscillator circuit can be connected to it. CKO is available
as a general purpose input, and/or HALT restart input.
Table 2 shows the variation in the oscillator frequencies as
functions of the component (R and C) values.
>
5 x Power Supply Rise Time
FIGURE 6. Recommended Reset Circuit
(Continued)
c
).
DS101135-8
11
EXTERNAL OSCILLATOR
CKI can be driven by an external clock signal. CKO is avail-
able as a general purpose input and/or HALT restart control.
Note: 3k
(k ) (M )
(k )
TABLE 1. Crystal Oscillator Configuration, T
R1
3.3
5.6
6.8
0
0
0
R
TABLE 2. RC Oscillator Configuration, T
50 pF
R2
R
(pF)
100
100
1
1
1
82
C
C
200k
200 pF
External Oscillator Diagrams
FIGURE 7. Crystal R/C, and
(pF)
200 100–150
C1
30
30
CKI Freq
2.2 to 2.7
1.1 to 1.3
0.9 to 1.1
(MHz)
External Oscillator
Crystal Oscillator
R/C Oscillator
30–36
30–36
(pF)
C2
DS101135-9
Instr. Cycle
DS101135-11
DS101135-10
8.8 to 10.8
CKI Freq
3.7 to 4.6
7.4 to 9.0
(MHz)
0.455
(µs)
10
4
Conditions
A
V
V
V
Conditions
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CC
CC
CC
V
V
V
= 25˚C
A
CC
CC
CC
= 25˚C
= 5V
= 5V
= 5V
= 5V
= 5V
= 5V