HD64F2357F20V Datasheet, PDF (757/1049 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-chip Microcomputer H8S Family / H8S/2300 Series

5. The maximum writing count (N) must be set to the maximum writing time (t_P(max)) or less according the actual
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
z = 30 µs
7 ≤ n ≤ 1000 z = 200 µs
[In additional writing]
Writing count n
1≤n≤6
z = 10 µs
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_E(max)).
t_E(max) = wait time (z) after setting of bit E × maximum erasing count (N)
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_CL pin (a pin for internal voltage step down circuit) and V_SS pin to stabilize the internal
voltage. Figure 22-64 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.)
An external capacitor to
stabilize the internal voltage
V_CL
One 0.47-µF capacitor
or two 0.47-µF capacitors
connected in parallel
V_SS
Do not connect the VCC power-supply to the VCL pin.
If connected, the LSI may be permanently damaged.
Connect the V_CC power-supply to the other V_CC pin in the usual way.
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_CL pin.
Figure 22-64 V_CL Capacitor Connection Method
Rev.6.00 Oct.28.2004 page 727 of 1016
REJ09B0138-0600H