LC87F2924B Datasheet, PDF (25/28 Pages) Sanyo Semicon Device – CMOS IC FROM 26K byte, RAM 768 byte on-chip 8-bit 1-chip Microcontroller

LC87F2924B
Characteristics of a Sample Main System Clock Oscillation Circuit
Given below are the characteristics of a sample main system clock oscillation circuit that are measured using a
SANYO-designated oscillation characteristics evaluation board and external components with circuit constant values
with which the oscillator vendor confirmed normal and stable oscillation.
Table 1 Characteristics of a Sample Main System Clock Oscillator Circuit with a Ceramic Oscillator
Nominal
Frequency
Vendor
Name
Oscillator Name
12MHz
MURATA CSTCE12M0G52-R0
Circuit Constant
Operating
Voltage Range
C1
C2
Rf1
Rd1
[V]
[pF] [pF]
[Ω]
[Ω]
(10) (10) Open 680
3.0 to 5.5
Oscillation
Stabilization Time
typ
max
[ms]
[ms]
0.05
0.15
Remarks
Internal
C1, C2
8MHz
CSTCE8M00G52-R0
(10) (10) Open
1k
MURATA
CSTLS8M00G53-B0
(15) (15) Open
1k
2.5 to 5.5
2.5 to 5.5
0.13
0.12
0.4
Internal
0.4
C1, C2
4MHz
CSTCR4M00G53-R0
(15)
(15) Open 2.2k
MURATA
CSTLS4M00G53-B0
(15) (15) Open 2.2k
2.2 to 5.5
2.2 to 5.5
0.07
0.2
Internal
0.05
0.15
C1, C2
The oscillation stabilization time refers to the time interval that is required for the oscillation to get stabilized after VDD
goes above the operating voltage lower limit (see Figure 4).
Characteristics of a Sample Subsystem Clock Oscillator Circuit
Given below are the characteristics of a sample subsystem clock oscillation circuit that are measured using a SANYO-
designated oscillation characteristics evaluation board and external components with circuit constant values with which
the oscillator vendor confirmed normal and stable oscillation.
Table 2 Characteristics of a Sample Subsystem Clock Oscillator Circuit with a Crystal Oscillator
Nominal
Frequency
Vendor Name
Oscillator Name
Circuit Constant
C3
C4
Rf2
Rd2
Operating
Voltage
Range
Oscillation
Stabilization Time
typ
max
Remarks
[pF]
[pF]
[Ω]
[Ω]
[V]
[s]
[s]
32.768kHz
EPSON
TOYOCOM
MC-306
18
18
Open 560k
2.2 to.5.5
Applicable
1.3
3.0
CL value=
12.5pF
The oscillation stabilization time refers to the time interval that is required for the oscillation to get stabilized after the
instruction for starting the subclock oscillation circuit is executed and to the time interval that is required for the
oscillation to get stabilized after the HOLD mode is reset (see Figure 4).
Note: The components that are involved in oscillation should be placed as close to the IC and to one another as possible
because they are vulnerable to the influences of the circuit pattern.
CF1
CF2
Rf1
Rd1
C1
C2
CF
Figure 1 CF Oscillator Circuit
XT1
XT2
Rf2
Rd2
C3
C4
X’tal
Figure 2 XT Oscillator Circuit
0.5VDD
Figure 3 AC Timing Measurement Point
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