upd78f0103hmca1-5a4-a Renesas Electronics Corporation., upd78f0103hmca1-5a4-a Datasheet - Page 434

• Manufacturer Part Number: upd78f0103hmca1-5a4-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

434
Electrical
specifications
(standard
products, (A)
grade
products)
Electrical
specifications
((A1) grade
products)
Recommended
soldering
conditions
Function
Details of Function
High-speed
system clock
(external RC)
oscillator
External RC
oscillation
frequency
Recommended
oscillator
constants
Absolute
Maximum Ratings
High-speed
system clock
(crystal/ceramic)
oscillator
High-speed
system clock
(external RC)
oscillator
−
When using the RC oscillator, wire as follows in the area enclosed by the broken lines in the
above figure to avoid an adverse effect from wiring capacitance.
• Keep the wiring length as short as possible.
• Do not cross the wiring with the other signal lines.
• Do not route the wiring near a signal line through which a high fluctuating current flows.
• Always make the ground point of the oscillator capacitor the same potential as V
• Do not ground the capacitor to a ground pattern through which a high current flows.
• Do not fetch signals from the oscillator.
R = 6.8 kΩ, C = 22 pF Target value: 3 MHz
R = 4.7 kΩ, C = 22 pF Target value: 4 MHz
Set one of the above values to R and C.
The oscillator constants shown above are reference values based on evaluation in a
specific environment by the resonator manufacturer. If it is necessary to optimize the
oscillator characteristics in the actual application, apply to the resonator manufacturer for
evaluation on the implementation circuit. The oscillation voltage and oscillation frequency
only indicate the oscillator characteristic. Use the 78K0/KB1+ so that the internal operation
conditions are within the specifications of the DC and AC characteristics.
Product quality may suffer if the absolute maximum rating is exceeded even momentarily
for any parameter. That is, the absolute maximum ratings are rated values at which the
product is on the verge of suffering physical damage, and therefore the product must be
used under conditions that ensure that the absolute maximum ratings are not exceeded.
When using the crystal/ceramic oscillator, wire as follows in the area enclosed by the
broken lines in the above figures to avoid an adverse effect from wiring capacitance.
• Keep the wiring length as short as possible.
• Do not cross the wiring with the other signal lines.
• Do not route the wiring near a signal line through which a high fluctuating current flows.
• Always make the ground point of the oscillator capacitor the same potential as V
• Do not ground the capacitor to a ground pattern through which a high current flows.
• Do not fetch signals from the oscillator.
Since the CPU is started by the internal oscillation clock after reset is released, check the
oscillation stabilization time of the crystal/ceramic oscillation clock using the oscillation
stabilization time counter status register (OSTC). Determine the oscillation stabilization
time of the OSTC register and oscillation stabilization time select register (OSTS) after
sufficiently evaluating the oscillation stabilization time with the resonator to be used.
When using the RC oscillator, wire as follows in the area enclosed by the broken lines in the
above figure to avoid an adverse effect from wiring capacitance.
• Keep the wiring length as short as possible.
• Do not cross the wiring with the other signal lines.
• Do not route the wiring near a signal line through which a high fluctuating current flows.
• Always make the ground point of the oscillator capacitor the same potential as V
• Do not ground the capacitor to a ground pattern through which a high current flows.
• Do not fetch signals from the oscillator.
R = 6.8 kΩ, C = 22 pF Target value: 3 MHz
R = 4.7 kΩ, C = 22 pF Target value: 4 MHz
Set one of the above values to R and C.
Do not use different soldering methods together (except for partial heating).
APPENDIX D LIST OF CAUTIONS
User’s Manual U16846EJ3V0UD
Cautions
SS
SS
SS
.
.
.
p. 372
p. 372
p. 373
p. 384
p. 385
p. 385
p. 386
p. 386
p. 398
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