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MB89530H Series
16
9. Details of the C pin handling for MB89530H series
MB89530H series contains the following products and the operating characteristics vary with whether they
contain the internal stepdown circuit.
Pin handling for the products depending on the internal voltage step-down circuit
Part number
Operating voltage
Voltage step-down circui
t
The same built-in resources are used for the above product types; operating sequences after the power-on reset
are different depending on whether they have the internal voltage step-down circuit.
The operating sequences after the power-on reset with the different models will be described below.
Operating sequences after the power-on reset with the different models
Pin type
Pin handling
MB89PV530
2.7 V to 5.5 V
Not included
N.C. pin
Not required
MB89P538
2.7 V to 5.5 V
Included
C pin
Fixed to V
CC
Not included
Fixed to V
SS
0.1
μ
F capacitor connected
0.1
μ
F capacitor connected
MB89537H/537HC
3.5 V to 5.5 V
Included
C pin
MB89538H/538HC
3.5 V to 5.5 V
Included
C pin
(2
18
/F
CH
)
(2
19
/F
CH
)
Voltage step-down circuit stabilization time +
oscillation stabilization time
Oscillation stabilization
time
Start of CPU operation for the prod-
uct not having the internal voltage
step-down circuit (reset vector)
Start of CPU operation for the
product having the internal voltage
step-down circuit (reset vector)
Power supply (V
CC
)
CPU operation of the product
having the internal voltage step-
down circuit (MB89537H/
537HC, MB89538H/538HC,
MB89P538*)
CPU operation of the product
not having the internal voltage
step-down circuit (MB89PV530,
MB89P538*)
F
CH
: Crystal oscillator frequency
*: With the MB89P538, you can select the voltage step-down circuit to be included or not by introducing the
C pin handling.
Note: As described above, CPU starts at delayed time with the product having the internal voltage step-
down circuit compared with the product not having the internal voltage step-down circuit. This is
because the time should be allowed for the stabilization time for voltage step-down circuit for normal
operation.