LC87F1HC4A Datasheet, PDF (23/27 Pages) Sanyo Semicon Device – CMOS IC 128K-byte FROM and 12288-byte RAM integrated 8-bit 1-chip Microcontroller with USB-host controller

LC87F1HC4A
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 shows the characteristics of a oscillation circuit when USB host function is not used.
If USB host function is to be used, it is absolutely recommended to use an oscillator that satisfies the precision and
stability according to the USB standards.
Table 1 Characteristics of a Sample Main System Clock Oscillator Circuit with a Ceramic Oscillator
Nominal
Frequency
Vendor
Name
Oscillator Name
Circuit Constant
C1
C2
Rd1
[pF]
[pF]
[Ω]
Operating
Voltage
Range
[V]
Oscillation
Stabilization Time
typ
max
[ms]
[ms]
Remarks
6MHz
MURATA CSTCR6M00GH5L**-R0 (39)
(39)
1k
2.7 to 5.5
0.1
0.5
8MHz
MURATA CSTCE8M00GH5L**-R0 (33)
(33)
470
3.0 to 5.5
0.1
0.5
10MHz
MURATA CSTCE10M0GH5L**-R0 (33)
(33)
330
3.0 to 5.5
0.1
0.5
12MHz
MURATA CSTCE12M0GH5L**-R0 (33)
(33)
330
3.0 to 5.5
0.1
0.5
C1 and C2
integrated
SMD type
The oscillation stabilization time refers to the time interval that is required for the oscillation to get stabilized in the
following cases (see Figure 4):
• Till the oscillation gets stabilized after VDD goes above the operating voltage lower limit.
• Till the oscillation gets stabilized after the instruction for starting the main clock oscillation circuit is executed
• Till the oscillation gets stabilized after the HOLD mode is reset.
• Till the oscillation gets stabilized after the X'tal HOLD mode is reset with CFSTOP (OCR register, bit 0) set to 0
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
Operating
Oscillation
Circuit Constant
Voltage
Stabilization Time
Oscillator Name
C3
C4
Rf
Rd2
Range
typ
max
Remarks
[pF]
[pF]
[Ω]
[Ω]
[V]
[s]
[s]
32.768kHz
EPSON
TOYOCOM
MC-306
18
18
OPEN 560k 2.7 to 5.5
1.1
Applicable
3.0
CL value=12.5pF
SMD type
The oscillation stabilization time refers to the time interval that is required for the oscillation to get stabilized in the
following cases (see Figure 4):
• Till the oscillation gets stabilized after the instruction for starting the subclock oscillation circuit is executed
• Till the oscillation gets stabilized after the HOLD mode is reset with EXTOSC (OCR register, bit 6) set to 1
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
Rd1
C1
CF
C2
Figure 1 CF Oscillator Circuit
XT1
Rf
XT2
Rd2
C3
X’tal
C4
Figure 2 Crystal Oscillator Circuit
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