CHAPTER 16 FLASH MEMORY (
µµµµ
PD70F3107A)
523
User’s Manual U14359EJ4V0UM
The self-programming interface is outlined below.
Figure 16-4. Outline of Self-Programming Interface
Application program
Entry program
RAM parameter
Device internal processing
Flash memory
Self-programming
interface
Flash-memory manipulation
16.7.4 Hardware environment
To write or erase the flash memory, a high voltage must be applied to the V
PP
pin. To execute self-programming, a
circuit that can generate a write voltage (V
PP
) and that can be controlled by software is necessary on the application
system. An example of a circuit that can select a voltage to be applied to the V
PP
pin by manipulating a port is shown
below.
Figure 16-5. Example of Self-Programming Circuit Configuration
V
DD
= 3.3
±
0.3 V
PD70F3107A
V
DD
V
SS
V
PP
Output port
IC for power supply
OUTPUT
INPUT
ON/OFF
V
SS
10 k
Ω
≥
10 k
Ω
V
IN
µ
(V
PP
= 7.8
±
0.3 V)
