Notes On Use; Usage Note (Internal Voltage Step Down For The H8S/2398 F-Ztat) - Renesas H8S Series Hardware Manual

5. The maximum writing count (N) must be set to the maximum writing time (t
set value (z). Wait time (z) must be switched after setting of bit P according to writing count (n).
Writing count n
1 ≤ n ≤ 6
7 ≤ n ≤ 1000
[In additional writing]
Writing count n
1 ≤ n ≤ 6
6. Wait time (z) after setting of bit E and the maximum erasing count (N) have the following relationship to the
maximum erasing time (t
(max) = wait time (z) after setting of bit E × maximum erasing count (N)
t
E
22.4

Notes on Use

The F-ZTAT and masked ROM versions satisfy electrical characteristics described in this manual. However, actual
electrical characteristics values, operation margins, and noise margins depend on differences in manufacturing processes,
on-chip ROM, or layout patterns.
If the system is evaluated using the F-ZTAT version, perform the same evaluation test of the system using the masked
ROM version when switching to the masked ROM version.
22.5

Usage Note (Internal Voltage Step Down for the H8S/2398 F-ZTAT)

The H8S/2398 F-ZTAT have a voltage step down circuit that automatically lowers the power supply voltage, inside the
microcomputer, to an adequate level. A capacitor (one 0.47-µF capacitor or two 0.47-µF capacitors connected in parallel)
should be connected between the V
voltage. Figure 22-64 shows how to connect the capacitor. Do not connect the V
could permanently damage the LSI. (Connect the V
z = 30 µs
z = 200 µs
z = 10 µs
(max)).
E
pin (a pin for internal voltage step down circuit) and V
CL
An external capacitor to
stabilize the internal voltage
One 0.47-µF capacitor
or two 0.47-µF capacitors
connected in parallel
Do not connect the V
CC
If connected, the LSI may be permanently damaged.
Connect the V power-supply to the other V
CC
Use a multilayer ceramic capacitor (one 0.47-µF capacitor or two 0.
47-µF capacitors connected in parallel) for this circuit, and place it/them
near the V pin.
CL
Figure 22-64 V
power-supply to the V
CC
V
CL
V
SS
power-supply to the V
CL
pin in the usual way.
CC
Capacitor Connection Method
CL
(max)) or less according the actual
P
pin to stabilize the internal
SS
power-supply to the V
CC
pin, in the usual way.)
CC
pin.
Rev.6.00 Oct.28.2004 page 727 of 1016
pin. Doing so
CL
REJ09B0138-0600H