upd75212a Renesas Electronics Corporation., upd75212a Datasheet - Page 49

• Manufacturer Part Number: upd75212a
• Description: 4-bit Single-chip Microcomputer
• Manufacturer: Renesas Electronics Corporation.

* 1. Recommended resonators are shown in following page.
Note
SUBSYSTEM CLOCK OSCILLATOR CHARACTERISTICS (Ta = –40 to +85 C, V
RESONATOR
Crystal
resonator*1
External
clock
2. Oscillator characteristics only. Refer to the description of AC characteristics for instruction execution time.
3. Oscillation stabilization time is a time required for oscillation to become stabilized after V
minimum value in the oscillation voltage range.
When the subsystem clock oscillator is used, the following should be noted concerning wiring in the area
in the figure enclosed by a dotted line to prevent the influence of wiring capacitance, etc.
• The wiring should be kept as short as possible.
• No other signal lines should be crossed. Keep away from lines carrying a high fluctuating current.
• The oscillator capacitor grounding point should always be at the same potential as V
• A signal should not be taken from the oscillator.
The subsystem clock oscillator is a low-amplitude circuit in order to achieve a low consumption current,
and is more prone to misoperation due to noise than the main system clock oscillator. Particular care is
therefore required with the wiring method when the subsystem clock is used.
to a ground pattern carrying a high current.
RECOMMENDED CIRCUIT
C3
XT1
XT1
Leave Open
XT2
XT2
C4
R
Oscillator frequency
(f
XT1 input frequency
(f
XT1 input high and low
level widths (t
Oscillation stabilization
time *3
XT
XT
) *2
)
PARAMETER
XTH
, t
XTL
)
V
TEST CONDITIONS
DD
= 4.5 to 6.0 V
DD
= 2.7 to 6.0 V)
MIN.
32
32
10
32.768
TYP.
1.0
SS
. Do not connect
DD
MAX.
PD75212A
100
35
10
32
2
reaches the
UNIT
kHz
kHz
s
s
s
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