Product data

128
22.3.5 Usage Note
(1) The F-ZTAT and mask ROM versions have been confirmed as fully meeting the reference
values for electrical characteristics shown in this manual. However, actual performance
figures, operating margins, noise margins, and other properties may vary due to differences in
the manufacturing process, on-chip ROM, layout patterns, etc.
When system evaluation testing is carried out using the F-ZTAT version, the same evaluation
tests should also be conducted for the mask ROM version when changing over to that version.
(2) On-chip power supply step-down circuit
The H8S/2128 F-ZTAT does not incorporate an internal power supply step-down circuit.
When changing over to F-ZTAT versions or mask ROM versions incorporating an internal
step-down circuit, the V
CC2
pin has the same pin location as the V
CL
pin in a step-down circuit.
Therfore, note that the circuit patterns differ between these two types of products.
External capacitor for
stabilizing power supply
By-pass
capacitor
FP-64A, TFP-80C: 6 pin
DP-64S: 14 pin
Product not
incorporating
step-down circuit
FP-64A, TFP-80C: 8 pin
DP-64S: 16 pin
FP-64A, TFP-80C: 6 pin
DP-64S: 14 pin
Product incorporating
internal step-down
circuit
FP-64A, TFP-80C: 8 pin
DP-64S: 16 pin
V
CC2
(V
CL
)
V
SS
V
CC2
V
CC
power supply
V
SS
0.47 µF
one or two
connected
in series
10 µF 0.01 µF
For products incorporating an internal step-down
circuit, do not connect the V
CL
pin to the V
CC
power supply. (The V
CC1
pin must be connected
to the V
CC
power supply as usual.)
The power supply stabilization capacitor must be
connected to the V
CL
pin. Use a monolithic
ceramic capacitor of 0.47 µF(one or two
connected in series) and locate it near the pins.
In case the power supply voltage is lower than
3.6 V, connect the capacitor in the same way as
the case with no step-down circuit incorporated.
<Products incorporating internal step-down
circuit>
HD6432128S, HD6432128SW,
HD6432127S, HD6432127SW
The location of the V
CC2
(V
CC
power supply) pin
in the product not incorporating an internal step-
down circuit, is the same as the V
CL
pin in a
product incorporating an internal step-down
circuit.
It is recommended that the by-pass capacitors
are connected to the power supply terminal
(these are reference values).
<Products not incorporating internal step-down
circuit>
HD64F2128, HD64F2128V,
HD6432127R, HD6432127RW,
HD6432126R, HD6432126RW,
HD6432122, HD6432120,
HD6432128SV, HD6432128SVW,
HD6432127SV, HD6432127SVW
Figure 22.49 Connection of External Capacitor (mask ROM type incorporating step-down
circuit and product not incorporating step-down circuit)