upd78f0148m1gka1-9eu Renesas Electronics Corporation., upd78f0148m1gka1-9eu Datasheet - Page 660

• Manufacturer Part Number: upd78f0148m1gka1-9eu
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

660
µ
Electrical
specifications
PD78F0148
Function
Subsystem
clock oscillator
REGC pin
UART0,
UART6
Absolute
maximum
ratings
X1 oscillator
Details of
Function
Be sure to connect the REGC pin in either of the following ways.
• To GND via a 1
• Directly to V
When connecting the REGC pin to GND via a 1
be supplied from the CLK pin of the flash programmer.
Create an oscillator on the board to supply a clock.
When UART0 or UART6 is selected, the receive clock is calculated based on
the reset command sent from the dedicated flash programmer after the V
pulse has been received.
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 X1 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
• Always make the ground point of the oscillator capacitor the same potential
• Do not ground the capacitor to a ground pattern through which a high current
• 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 X1 input 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 subsystem clock 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
• Always make the ground point of the oscillator capacitor the same potential
• Do not ground the capacitor to a ground pattern through which a high
• Do not fetch signals from the oscillator.
The subsystem clock oscillator is designed as a low-amplitude circuit for
reducing power consumption, and is more prone to malfunction due to noise
than the X1 oscillator. Particular care is therefore required with the wiring
method when the subsystem clock is used.
current flows.
as V
current flows.
current flows.
as V
flows.
SS
SS
APPENDIX D LIST OF CAUTIONS
.
.
User’s Manual U15947EJ3V1UD
DD
µ
F capacitor
Cautions
µ
F capacitor, the clock cannot
PP
pp. 489,
490
pp. 489,
490
p. 505
pp. 521,
546, 570,
571, 591,
592
pp. 522,
547,
572,
593
pp. 522,
547,
572,
593
pp. 523,
548,
573,
594
pp. 523,
548,
573,
594
Page
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