D12320VF25V Datasheet, PDF (895/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 20 Electrical Characteristics
20.3.7 Usage Note (Internal voltage step down for the H8S/2319C F-ZTAT)
The H8S/2319C F-ZTAT has an on-chip voltage step down circuit that automatically lowers the
power supply voltage, inside the microcomputer, to an adequate level. A capacitor (0.1 µF) should
be connected between the internal voltage step down circuit pin (V_CL pin) and the V_SS pin to
stabilize the internal voltage. Figure 20.23 shows how to connect the capacitor. Do not connect the
V_CC power supply to the V_CL pin. Doing so could permanently damage the LSI. (Connect the V_CC
power-supply to the V_CC pin, in the usual way.)
External capacitor
to stabilize the
power supply
V_CL
0.1 μF
V_SS
Do not connect the V_CC power-supply to the V_CL pin.
Doing so could permanently damage the LSI. (Connect
the V_CC power-supply to the V_CC pin, in the usual way.)
Use a multilayer ceramic capacitor (0.1 μF), and place
it near the pins.
Figure 20.23 V_CL Capacitor Connection Method
20.4 Usage Note
Although both the F-ZTAT and mask ROM versions fully meet the electrical specifications listed
in this manual, there may be differences in the actual values of the electrical characteristics,
operating margins, noise margins, and so forth, due to differences in the fabrication process, the
on-chip ROM, and the layout patterns.
If the F-ZTAT version is used to carry out system evaluation and testing, therefore, when
switching to the mask ROM version the same evaluation and testing procedures should also be
conducted on this version.
Rev.7.00 Feb. 14, 2007 page 861 of 1108
REJ09B0089-0700